Dissertations / Theses: 'Silver deposits'

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Ahlzén, Ewa. "Ädelmetalldeponeringar på Gotland under vikingatid : Gömda eller undanlagda?" Thesis, Södertörns högskola, Institutionen för historia och samtidsstudier, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-28385.

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The Viking Age (800–1050 A.D.) is also called the “Silver Age”. Despite the fact that no silver mines were in use in Sweden at that time, most of the landowners for one reason or another had a lot of precious metal stored in their homes. Alone the Island of Gotland has found over 700 different hoards of which around 400 of these hoards have been excavated over the last 100 years. Archeologists are debating whether all this precious metal had been brought to the island by traders from the east, or if it came from the Viking raids in the west. Besides the coins, thousands of pieces of silver have been recorded. The intention of this essay is to attempt to clarify if it is possible to find differentiating factors between the hoards and to classify categories of these precious metal deposits. I indeed, such classifications and categorizations are achievable in the research findings in this paper.

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Moncada, de la Rosa Jorge Daniel. "Winning Silver." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/52861.

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The search for mineral deposits is a time consuming, risky and very expensive process. Applying new models and methods provides a competitive advantage in the search for mineral deposits because an explorationist can quickly evaluate potential targets and eliminate areas without good potential for mineralization. This dissertation presents a practical technique for prediction to finding precious metal mineralization at Guanajauato mining district (GMD) base on theoretical and experimental studies of fluids properties, mineral phase equilibrium, physical and chemical mechanisms. Making the technique highly transportable so that it can be applied in the field during an exploration program base on petrographic characteristics of mineral textures produced during boiling events in quartz, calcite and adularia, and fluid inclusions contained in these phases. While this work was conducted in GMD, the results should be applicable in exploration for epithermal deposits worldwide. The GMD is one of the largest silver producing districts in the world. Ore shoots are localized along three major northwest trending vein systems, the La Luz, Veta Madre and Vetas de la Sierra. More than 1200 samples were collected from surface outcrops, underground mine and historical and recent drill core. Traverses perpendicular to veins in all system were also conducted. Most of the samples (approximately 90%) were also assayed for Au, Ag, Cu, Pb, Zn, As, Sb. Samples from the GMD show a wide range in silica textures are indicative of rapid precipitation, such as occurs when fluids boil. Other mineral phases, including illite, rhombic adularia and bladed calcite are also indicative of rapid growth in a hydrothermal system and are characteristic of boiling systems. Because boiling is an effective mechanism for precipitating gold and silver from hydrothermal fluids, the presence of mineral textures indicative of boiling is a desirable feature in exploration. In many samples, textural evidence for boiling is supported by coexisting liquid-rich and vapor-rich fluid inclusions, or Fluid Inclusion Assemblages consisting of only vapor-rich inclusions, suggesting "flashing" of the hydrothermal fluids. Textural and fluid inclusion evidence for boiling has been observed in the deepest levels of the GMD, suggesting that additional precious metal resources may occur beneath these levels.
Ph. D.

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Thomson, Brian. "Geology of silver mineralisation at Candelaria, Nevada, USA." Thesis, University of Aberdeen, 1990. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=238078.

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Candelaria, situated in central western Nevada, along the western margin of the Great Basin, is a large and predominantly low grade, epigenetic disseminated- and vein-type Ag deposit, of Early Cretaceous age. It represents the eroded, deeply oxidised and fault-disrupted root of extensive stratiform quartz-dolomite stockworked and sericite-dolomite-altered zones of medium temperature pyrite-dominated Ag(-Pb-Zn-Sb-As±Cu±Au) sulphide-sulphosalt mineralisation, which is hosted by receptive sedimentary and igneous rocks within structurally favourable zones in a district-scale tectonic pinchout, and which is genetically associated with Cordilleran granodiorite porphyry hypabyssal magmatism (diking), of high K calc-alkaline affinity. The mineralisation occurs along and directly beneath the Pickhandle allochthon, a serpentinite-sheathed volcanic-sedimentary tectonic méange which forms a local 'sole' plate to the regionally extensive Golconda allochthon, which was emplaced onto the edge of continental North America during the Early Triassic Sonoma orogeny. Mineralisation occurred where an irregularity in the Pickhandle thrust plane, caused by thickening of the méange, effected locally deeper truncation of the parautochthonous foreland sequence in its footwall - chiefly marine sediments of the Lower Triassic Candelaria Formation - against the deformed cherts of the Ordovician basement (Palmetto complex), to form a structural trap. Within this trap, mineralisation is hosted mainly by carbonaceous, carbonate- and phosphate-rich (and trace metal-rich) black shales at the base of the Candelaria Formation and by dolomite-quartz-altered serpentinites at the base of the Pickhandle allochthon. Stable isotope data (O, H, S) point to a predominantly magmatic source for the hydrothermal fluids and ore sulphur, a source most likely to be the parent pluton to the granodiorite porphyry dikes. More ore metals were also of igneous origin (mass balance calculations rule out Candelaria member 1 as the chief metal source).

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Whitbread, Michael Andrew Ian, and n/a. "Lithogeochemichal alteration aound the Century and Elura Zn-Pb-Ag deposits: detecting alteration expressions in deep and near surface environments." University of Canberra. Resource, Environmental & Heritage Sciences, 2004. http://erl.canberra.edu.au./public/adt-AUC20051129.112425.

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Exploration companies commonly rely on geochemistry to identify alteration of distinctive geochemical and mineralogical character, surrounding metal sulphide deposits that were precipitated from hydrothermal fluids. However, examination of raw analytical data is prone to error due to closure effects and the difficulty in removing the effects of background variation in unaltered rocks from the variations imposed by later hydrothermal alteration. Closure can be avoided by using ratios, or by utilising mass balance approaches based on fixing volume, mass or concentration changes between samples of parent and daughter lithologies. Using a parent-daughter approach is limiting, because only pairs of samples can be compared at any one time and because an unaltered equivalent must be produced for each sample examined in this way. Pearce Element Ratio analysis and General Element Ratio analysis (PER and GER) are not restricted in this fashion, and are more amenable to interrogation of large data sets. PER and GER are also capable of decoupling background variation from that variation due to hydrothermal alteration. Furthermore, these ratio methods are readily applied to commercially derived lithogeochemical assays. In this study, various analytical methods and interpretive techniques (including PER and GER) have been applied to identify alteration in rocks around the Century and Elura Zn-Pb-Ag deposits, and to assess whether primary ore-related alteration effects can still be identified once altered rocks have been subjected to weathering. Ratios of trace elements over a conserved element have been used to generate a suite of pathfinder elements for each deposit. Elements enriched in host rocks around both deposits include the economic metals Zn, Pb and Ag, along with Rb and Tl. Sodium is ubiquitously depleted in altered rocks. Other elements in the pathfinder suites are distinctive to each deposit type, and include a number of major and trace elements that are added or removed from the rocks around the mineralised zones. For example, Sb and As are enriched in rocks around Elura mineralisation while Ge and Cd are enriched in samples around Century deposit. Iron carbonate development accompanied by potassic alteration, the destruction of albite and the absence of chlorite are the dominant mineral alteration effects at both deposits. PER and GER diagrams have been used to quantify the intensity of this alteration and allow lithogeochemistry to be used to vector towards high intensity alteration, which is adjacent to Century and Elura mineralisation. These ratio methods are applied to both visibly and cryptically altered rocks at both deposits, and have a very high degree of success in classifying alteration in unweathered rocks. The following simple PER ratios indicate proximity to Elura mineralisation: Ca/C, K/Al for shales, K/(Al-Na) for siltstones/sandstones. The following simple PER ratios indicate proximity to Century mineralisation: Mn/Ti, Mg/Ti and Fe/Ti vs C/Ti, K/Ti vs Al/Ti, K/Ti vs (Al-Na)/Ti. Pathfinder elements can be overlain onto PER and GER diagrams to aid in ranking the prospectivity of samples, and to assess mineral hosts for individual pathfinder elements. Weathering destroys most indicators of alteration in the Elura area, while alteration signatures are better preserved in host rocks around the Century deposit.

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Nowak, Marek Stanislaw. "Ore reserve estimation, Silver Queen vein, Owen Lake, British Columbia." Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/30028.

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The Silver Queen polymetallic vein system south of Houston, B.C., can be treated as a 2-dimensional problem for purposes of reserve/resource estimation. Complexities in obtaining reserve/resource estimates arise from (i) uncertainties in geological interpolation and extrapolation of the vein system, (ii) uncertainties in the distinction between vein and highly altered wallrock in some old drill logs, (iii) complex and multivariable geological character of the vein, (iv) a limited number of exploration drill holes and (v) a different support for drift and drill hole data. Each of these problems has been considered in detail. The study comprises geological analysis, data analysis, point kriging (analysis of thickness and metal distribution) block kriging and comparison of reserve/resource estimation by various procedures including ordinary kriging, inverse squared distance weighting, and polygonal methods. A novel component of the investigation is the use of correlograms (in reality, 1 minus the correlogram) as a substitute for the variogram in geostatistical estimates. This procedure was tested as a means of defining continuity of DDH and Drift assay data of differing support. Ordinary kriging of large polygonal blocks provides metal contents more or less comparable to but locally more conservative than polygonal results reported in a recent feasibility study. Differences are in part due to the use of somewhat different data for the two procedures. The effect of the volume of the selective mining unit on the recovered tonnage and grade is described and limitations of the indirect lognormal method are presented.
Applied Science, Faculty of
Mining Engineering, Keevil Institute of
Graduate

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Cauchois, Romain. "Microstructuring inkjet-printed deposits from silver nanoparticules coalescence to the fabrication of interconnections for electronic devices." Phd thesis, Ecole Nationale Supérieure des Mines de Saint-Etienne, 2012. http://tel.archives-ouvertes.fr/tel-00847021.

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Several challenges are still holding back the technological transfer of printed electronics to industry in spite of recent progresses. In this thesis work, the printing method of inks based on silver nanoparticles (<Ø>=25 nm) was optimized according to its rheology and to the fluid/substrate interactions for the fabrication of electrical interconnections with a thickness of 500 nm. These lines were printed on silicon or flexible substrates and annealed either by conventional (oven or infrared) or selective methods (microwave) at temperatures comprised between 100 and 300 °C.A better understanding of the relationship between process and microstructure of these printed thin films, based on several crystallographic equipments (XRD, EBSD and EDX), led to the optimization of nanocrystallites growth with an activation energy of about 3 to 5 kJ*mol-1. In addition to the low residual stress (70 MPa), this optimization is used to achieve low electrical resistivity (3.4 μOhm*cm) associated with a greater coherence of the crystal lattices at grain boundaries. The probability of electron scattering at such interfaces can be further reduced using an innovative approach of oriented crystallite growth by atomic interdiffusion from the substrate.The low mechanical stiffness (E<50 GPa) of these porous lines requires a reinforcement step either by crystalline texturation or by electroless growth to withstand the assembly and wire-bonding steps. The fabrication of a functional demonstrator thus validated the printing technology for the manufacture of electronic components.

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Wiberg, Steen Tobias. "Genetic relationships and origin of the Ädelfors gold deposits in Southeastern Sweden." Thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-67912.

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Ädelfors is situated ca 17 km east of Vetlanda, Jönköping County, in the N-S striking Trans-scandinavian igneous belt and is a part of the NE-SW striking 1.83-1.82 Ga Oskarshamn-Jönköping belt emplaced during a continental subduction towards the Svecofennian continental margin. The continental arc hosts the 1.83 Ga metasedimentary Vetlanda supergroup composed of foliated metagreywacke, metasandstone and metaconglomerate. The sequence is intercalated by mafic and felsic volcanites and hosts the Cu-Au-Fe-mines at Ädelfors. Ädelfors mining field consists of ca 330 mineralized quartz veins hosting both copper, gold and iron. The iron mines Nilsson’s iron mine (NFE) and Fe-mine (FE), the copper mine Kamelen (KM) and the gold mines Brånad’s mine (BR), Adolf Fredrik’s mine (AF), Old Kron mine (GKR), Old Kolhag’s mine (GKO), Thörn mine (TH), New Galon mine (NG), Stenborg’s mine (ST), Tysk mine (TG), Hällaskallen (HS) and Fridhem (FR) have been investigated to deduce a possible genetic relation between the veins and their origin. Sulfur isotope ratios have also been conducted on pyrite from KM, AF and FE. The veins can stucturally be divided into several groups. AF, GKR, ST, NG, TH and possibly NFE are striking 10-70° with a dip of 55-70°. BR, GKO and KM are striking 110-140° with a dip of 80-90° whereas TG and HS strike 90-110° dipping 85°. Fridhem, being distal to the other mines, strikes 70° and dips 80°. A chlorite-quartz-biotite-sericite-rich metapelite hosts the veins in all localities except; FR where a layered, beresitizised felsic volcanite rich in plagioclase, sericite, biotite and quartz hosts disseminated pyrite; and NFE, HS and NG which are hosted by a mafic tuffite. Quartz veins are mainly milky and equigranular, exceptions are FE with black pyrite-bearing quartz veins, cutting through the banded magnetite-metapelite and KM with its dynamically recrystallized quartz. Chlorite-, zeolite-, carbonate-, hematite-, amphibole-, kalifeldspar-, sericite-, biotite- and epidote alteration has been observed among the localities. The ore minerals are dominated by: fractured sub- to euhedral pyrite in cataclastic aggregates or selvage bands, interstitial chalcopyrite in pyrite, marcasite, pyrrhotite, gold and sporadic chalcopyrite diseased sphalerite and arsenopyrite. Previously not reported tetradymite, staurolite, galena and Ce-monazite have also been observed. Bismuthinite and tetradymite as inclusions in pyrite were observed in AF, GKR, FR and TG. Gold was observed in AF, BR, GKR and TG as inclusions in pyrite or quartz with a Au/Ag median of 78.41. HS distinguishes itself with Au/Ag ratios of 4.66-5.25. The trace element ratios in pyrite reveal two major types of pyrite. 1) found in FE and KM (pyrite type 1) with Co/Ni ratio of 10.94, Bi/Au of 1.79, Bi/S of 0.037, Au/Ag of 11.13, S/Se of 235.96 and As/S of 0.006. 2) found in NG, GKO, ST, TH, AF, NFE, HS, GKR, BR, FR, TG and as stringers in KM4 py1 pyrite type 2) with an average Co/Ni ratio of 5.26, Bi/Au of 1.95, Bi/S of 0.031, Au/Ag of 4.19, S/Se of 0 and As/S of 0. δ34S values strengthens this grouping as KM and FE has 1,3-2,6 ‰ and AF 3,6-3,8 ‰. The following geological interpretation has been concluded: The banded iron formation in FE is the earliest mineralization and was later fractured, emplacing quartz veins with pyrite of type 1. During this event, the Cu-vein in KM was also formed. A second generation of fractures, emplaced after the Småland granitoids formed, were filled with quartz and pyrite of type 2 at mesozonal depth. This is the main stage of gold mineralization and includes NG, GKO, ST, TH, AF, NFE, GKR, BR, FR and TG. During this event, pyrite of type 2 was added to KM, causing recrystallizing of the quartz. HS is possibly emplaced last or altered as it is more enriched in silver. Morphology, mineralogy, alterations, mineral chemistry and sulfur isotope signatures indicates an orogenic origin of the gold-rich quartz veins at Ädelfors as well as the copper-rich vein in KM.
Ädelfors ligger ca 17 km öster om Vetlanda, Jönköpings län, i det N-S strykande Transskandinaviska granit och porfyrbältet och är en del av det NÖ-SV strykande 1,83-1,82 Ga Oskarshamn-Jönköpingsbältet (OJB) bildad i en kontinental subduktionszon i kanten av den Svecofenniska kontinentalplattan. I denna kontinentalbåge ligger Vetlanda supergruppen som är en metasedimentär del av OJB bestående av starkt folierad 1,83 Ga metagråvacka, metasandsten och metakonglomerat med inlagringar av mafiska och felsiska vulkaniter. Ädelfors gruvfält består utav ca. 330 kvartsgångar förande mestadels guld men också koppar. Järnmineraliseringar i form av bandad järnmalm finns också i området. Geologin, mineralogin och pyritens kemiska sammansättning från järngruvorna Nilssons järngruva (NFE) och Fe-gruvan (FE), koppargruvan Kamelen (KM) och guldgruvorna Brånadsgruvan (BR), Adolf Fredriks gruva (AF), Gamla Krongruvan (GKR), Gamla Kolhagsgruvan (GKO), Thörngruvan (TH), Nya Galongruvan (NG), Stenborgs gruva (ST), Tyskgruvan (TG), Hällaskallen (HS) och Fridhem (FR) har undersökts för att finna eventuella genetiska likheter. Svavelisotopförhållande har fastställts för pyrit från AF, FE och KM. Strukturellt kan gångarna delas in i ett antal grupper. AF, GKR, ST, NG, TH och möjligtvis NFE stryker 10-70° och stupar 55-70°. BR, GKO och KM stryker 110-140° och stupar 80-90° medan TG och HS stryker 90-110° och stupar 85°. Fridhem stryker 70° och stupar 80°. En klorit-kvarts-sericit-biotitrik metapelit utgör värdbergarten i alla gruvor förutom; FR där den utgörs av en beresitiserad felsisk vulkanit rik på plagioklas, sericit, biotit och kvarts med disseminerad pyrit; och NFE, HS, NG vilka har en mafisk tuffitisk moderbergart. Kvartsgångarna är mjölkvita med undantag för FE:s svarta, pyritförande kvarts vilket uppträder som sprickfyllnad i den bandade järnmalmen och är senare bildad. Kvartsen i KM är starkt dynamiskt omkristalliserad. Svag till måttlig foliation är vanlig i sidoberget med undantag av stark foliation i TG och NFE, vilka är lokaliserade i förkastningssprickor med stark kloritförskiffring av värdbergarten. Klorit-, zeolit-, karbonat-, hematit-, amfibol-, kalifältspat-, sericit-, biotit- och epidotomvandling förekommer i majoriteten av lokalerna. Malmmineralen är dominerande sprött deformerad subhedral till euhedral pyrit som kataklastiska aggregat eller band, interstitiell kopparkis i pyrit, markasit, magnetkis, guld och sporadiskt kopparkissjuk zinkblände och arsenikkis. I det här arbetet har även tetradymit, staurolit, blyglans och Ce-monazit observerats. Bismutinit och tetradymit i form av inneslutningar i pyrit observerades i AF, GKR, FR och TG. Guld observerades i AF, BR, GKR och TG som inneslutningar i pyrit eller fritt i kvarts med Au/Ag medianvärde på 78,41, avvikande är HS med värden mellan 4,66-5,25. Förhållanden mellan spårelement i pyrit indikerar två typer av pyrit. Typ 1 funnen i FE och KM har följande värden: Co/Ni = 10,94, Bi/Au = 1,79, Bi/S = 0,037, Au/Ag = 11,13, S/Se = 235,96 och As/S = 0,006. Typ 2 funnen i NG, GKO, ST, TH, AF, NFE, HS, GKR, BR, FR, TG och som sliror i KM4 py1 har följande värden Co/Ni = 5,26, Bi/Au = 1,95, Bi/S = 0,031, Au/Ag = 4,19, S/Se = 0 and As/S = 0. δ34S värden styrker denna uppdelning där KM och FE har värdena 1,3-2,6 ‰ och AF 3,6-3,8 ‰. Den geologiska utvecklingen av fältet har tolkats som följande: FE-gruvans bandade järnmalm är den tidigaste mineraliseringen vilket följs utav uppsprickning och läkning av kvarts med pyrit typ 1 som också bildar kopparmineraliseringen KM. Senare sprickzoner efter Smålandsgraniternas intrusion läks av kvarts med pyrit typ 2 på mesozonalt djup vilket bildar NG, GKO, ST, TH, AF, NFE, GKR, BR, FR, TG och omkristalliserar och introducerar nya pyritsliror i kvartsen i KM. HS bildas möjligtvis sist eller har blivit omvandlad eftersom den är anrikad på silver. Morfologi, omvandlingar och svavelisotop-signaturer tyder på ett orogent ursprung för Ädelfors guldrika kvartsådror samt den kopparrika kvartsådern i KM.

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Devlin, Barry David. "Geology and genesis of the Dolly Varden silver camp, Alice Arm area, northwestern British Columbia." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26243.

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The Dolly Varden camp, Alice Arm area, northwestern British Columbia, is characterized by stratiform and volcanogenic silver-lead-zinc-barite deposits in Early to Middle Jurassic calc-alkaline volcanic rocks of the Hazelton Group. These deposits, containing exceptional silver and significant base metal values, are in andesitic tuffaceous rocks, and occur typically as layers of quartz, carbonate, barite and jasper, with lesser amounts of pyrite, sphalerite and galena, and sparse chalcopyrite. Production from three deposits, the Dolly Varden, Northstar and Torbrit mines, totaled 1,284,902 tonnes of ore that averaged 484g silver per tonne, 0.38 percent lead and 0.02 percent zinc. The Hazelton Group is a thick, widespread assemblage of basaltic to rhyolitic volcanic flow rocks, their tuffaceous equivalents, and derived sedimentary rocks. Dolly Varden camp is underlain by more than 3,000m of Hazelton Group rocks comprised of one major volcanic and one major sedimentary formation. Volcanic rocks underlie sedimentary rocks and have been subdivided into footwall and hangingwall units based on stratigraphic position relative to the mineralized stratiform horizon. Footwall volcanic rocks consist of green ± maroon basaltic-andesite tuff, green ± maroon porphyritic andesite and green andesite shard tuff. Stratiform mineralization rests conformably upon the underlying green andesite shard tuff. Hangingwall volcanic rocks above the stratiform layer consist of pale grey basaltic-andesite ash tuff, maroon basaltic-andesite ash-lapilli tuff, grey-green porphyritic andesite, and pale green andesite ash tuff. Hangingwall volcanics are unconformably capped by sedimentary rocks consisting of maroon siltstone, calcareous and fossiliferous wacke, and black siltstone and shale; black siltstone and shale form the youngest rock unit of the Hazelton Group in the Dolly Varden area. Basalt and lamprophyre dykes intrude all rocks of the Hazelton Group. The rocks of the Hazelton group exposed in the Dolly Varden camp are folded into a series of anticlines and synclines with gentle, northwestern plunges. Two major sets of nearly vertical block faults cut all rock units; earlier faults trend northwest and younger faults trend north-northeast. Geological mapping, combined with petrologic, petrographic and isotopic data, indicate that the stratiform deposits probably formed as submarine exhalative deposits associated with andesitic volcanism of the Hazelton Group during the Early to Middle Jurassic. Evidence for a volcanogenic origin is the conformity of layered mineralization with stratigraphy, lateral and vertical mineral zonation patterns, consistent hangingwall versus footwall contact relationships, fragments of stratiform ore within tuffaceous volcanic rocks of the hangingwall, consistent differences in the stable isotopic compositions between the sulfides versus barite, quartz and carbonate gangue, and the Jurassic "fingerprint" for the lead-bearing deposits of the Dolly Varden camp. The Dolly Varden deposits display criteria for classification of a new, previously unrecognized, stratiform and volcanogenic, deposit type, named here, the "Dolly Varden type", and is characterized by silver-rich, low sulfide and high oxide stratiform mineralization within andesitic volcanic rocks.
Science, Faculty of
Earth, Ocean and Atmospheric Sciences, Department of
Graduate

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Hasten, Zachary Eugene Levi. "Mid-Miocene magmatism in the Owyhee Mountains, ID: origin and petrogenesis of volcanic rocks in the Silver City district." Thesis, Kansas State University, 2012. http://hdl.handle.net/2097/14940.

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Master of Science
Department of Geology
Matthew E. Brueseke
Previous studies of the northern Great Basin have indicated that mid-Miocene epithermal gold and silver ore deposits distributed regionally are temporally related to the magmatic activity associated with the onset of widespread extension and the Yellowstone hotspot (Saunders and Crowe, 1996; Kamenov et al., 2007). This study is focused on the volcanic rocks and ore deposits from the Silver City district (SCD), ID to address the petrogenesis and magmatic evolution that was influential in forming local precious metal deposits. The goal is to understand the tectonomagmatic conditions that contributed to the petrogenesis of the volcanic suite in the Silver City district, which can be used to provide details on the relationship between coeval mid- Miocene magmatism and mineralization across the northern Great Basin and Oregon Plateau. In order to better constrain the magmatic evolution of the SCD and potential sources of the precious metals, we have undertaken detailed sampling of local crust and mid-Miocene volcanic units to constrain their physical, geochemical, isotopic, and geochronological characteristics, as well as provide constraints on the petrogenesis of the mid-Miocene volcanic package. Prior studies of the local volcanism have yielded K-Ar and [superscript]40Ar/[superscript]39Ar ages of ~16.6 to 14 Ma (Bonnichsen, 1983), while others have dated adularia from one SCD mineral vein and obtained [superscript]40Ar/[superscript]39Ar ages of between 15.6 and 16.3 Ma (Hames et al., 2009; and Aseto et al., 2011). Field observations are consistent with earlier work (Lindgren, 1900; Asher, 1968; Pansze, 1975; Halsor et al., 1988; Bonnichsen and Godchaux, 2006; Camp and Ross, 2009) and reveal a sequence of basalt consisting of regionally prevalent Steens Basalt that pre-dated precious metal mineralization. Some of the basalt appears to have been erupted locally, based on the presence of mafic dikes and thick pyroclastic deposits similar to other regional mid-Miocene magmatic systems. Stratigraphically overlying this lower basalt suite is a complex package of rhyolite flows and domes, thin silicic pyroclastic units, additional basaltic lava flows, intermediate lava flows, and mafic/silicic shallow intrusives. Geochemical analysis indicates that the basaltic and basaltic andesite lava flows are locally erupted flows of Steens Basalt while the intermediate and silicic volcanism in SCD can be classified into nine distinct units including two andesites, one dacite, four rhyolites and two rhyolite tuffaceous units. Geochemical modeling suggest that the intermediate and silicic magmas were formed by a combination of open system processes, including low pressure partial melting and assimilation of mid to upper crustal granitoid basement rock, and magma mixing between silicic and basaltic endmembers. The formation of silicic volcanism in the SCD is similar to other regional mid-Miocene silicic volcanic systems (e.g. Santa Rosa-Calico volcanic field and Jarbidge Rhyolite). Based on new [superscript]40Ar/[superscript]39Ar geochronology of both volcanic units and epithermally emplaced mineralization, SCD volcanism appears to have erupted over a relatively short amount of time that overlaps with local epithermal Au-Ag mineralization.

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Egnell, Philip. "Från bitsilver till silvermyntning : – en undersökning av den monetära utvecklingen i den vikingatida ekonomin på Gotland." Thesis, Uppsala universitet, Institutionen för arkeologi och antik historia, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-385713.

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The purpose with this work is to try and see an economic development on Gotland during the Viking Age, where society went from a weight-based economy, to a monetary economy with its own coins. The aim is to try and distinguish a pattern in the investigated depots. How has the deposit structure changed during the Viking era when it comes to the minted and unminted silver? The research about the silver deposits aim on the dating of the coins in order to create an approximate closing period for the contents of the depots. The development of the silver structural change in the silver depots during the Viking Age makes it possible to study how the dominance of the early Islamic coins, in both coin and fragmented form, is phased out to be replaced by mainly English and German coins. The English and German coins that are found on Gotland could be seen as a model for the coins and the minting that began at the end of the Viking Age on the island.

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Winter, Lawrence Stephen. "The genesis of ‘giant’ copper-zinc-gold-silver volcanogenic massive sulphide deposits at Tambogrande, Perú : age, tectonic setting, paleomorphology, lithogeochemistry, and radiogenic isotopes." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/773.

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The ‘giant’ Tambogrande volcanogenic massive sulphide (VMS) deposits within the Cretaceous Lancones basin of northwestern Perú are some of the largest Cu-Zn-Au-Ag-bearing massive sulphide deposits known. Limited research has been done on these deposits, hence the ore forming setting in which they developed and the key criteria that permitted such anomalous accumulation of base-metal sulphides are not understood. Based on field relationships in the host volcanic rocks and U-Pb geochronology, the deposits formed during the early stages of arc development in the latest Early Cretaceous and were related to an extensional and arc-rift phase (~105-100 Ma, phase 1). During this time, bimodal, primitive basalt-dominant volcanic rocks were erupted in a relatively deep marginal basin. Phase 1 rhyolite is tholeiitic, M-type, and considered to have formed from relatively high temperature, small batch magmas. The high heat flow and extensional setting extant during the initial stages of arc development were essential components for forming a VMS hydrothermal system. The subsequent phase 2 (~99-91 Ma) volcanic sequence comprises more evolved mafic rocks and similar, but more depleted, felsic rocks erupted in a relatively shallow marine setting. Phase 2 is interpreted to represent late-stage arc volcanism during a waning extensional regime and marked the transition to contractional tectonism. The Tambogrande deposits are particularly unusual amongst the ‘giant’ class of VMS deposits in that deposition largely occurred as seafloor mound-type and not by replacement of existing strata. Paleomorphology of the local depositional setting was defined by seafloor depressions controlled by syn-volcanic faults and rhyolitic volcanism. The depressions were the main controls on distribution and geometry of the deposits and, due to inherently confined hydrothermal venting, enhanced the efficiency of sulphide deposition. Geochemical and radiogenic isotope data indicate that the rhyolites in the VMS deposits were high temperature partial melts of the juvenile arc crust that had inherited the isotopic signatures of continental crust. Moreover, Pb isotope data suggest the metal budget was sourced almost wholly from mafic volcanic strata. Therefore, unlike the implications of many conventional models, the felsic volcanic rocks at Tambogrande are interpreted to have only played a passive role in VMS formation.

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Camprubí, i. Cano Antoni. "Los depósitos epitermales de Ag-Au de Temascaltepec (Estado de México), México." Doctoral thesis, Universitat de Barcelona, 1998. http://hdl.handle.net/10803/667070.

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El distrito de Temascaltepec, situado en la parte SW del estado de México (México), consta de tres zonas principales con depósitos epitermales de baja sulfuración, denominados Mina de Agua, El Coloso y La Guitarra. Estos depósitos se hallan situados metalogenéticamente en la parte meridional del cinturón argentífero que se extiende paralelamente a la costa Pacífica de México. El inicio de la actividad minera conocida en la zona data del siglo XVI. El yacimiento más importante de distrito es el sistema La Guitarra, actualmente explotado para Ag-Au, que está compuesto por varios filones encajados en un stock granítico tardi-larámide, y se relaciona temporal y genéticamente con el vulcanismo andesítico-riolítico de la Sierra Madre Occidental. Dos dataciones en adularia mediante termocronología de Ar-Ar dieron edades entre 33.3 y 33.1 M.a. (Oligoceno inferior). Las leyes medias que contiene son de 3.23 ppm Au, 311 ppm Ag. 515 ppm Cu, 0,15% Pb y 0,29% Zn; las leyes de corte son 1.5 ppm Au y 150 ppm Ag. Las reservas existentes en el año 1997 se estimaron en 380,000 t. La Guitarra consta de tres fases principales de mineralización (I, II y III) y cuatro subfases (A, B, C y D) en la fase II. Las asociaciones minerales más tempranas en cada fase son sulfuros de metales de base, mientras que las más tardías contienen los minerales de Ag y Au, la abundancia relativa de los cuales aumenta con la elevación en el sistema y con el tiempo. La fase I carece de Au y su contenido de minerales de Ag es muy bajo. La fase III tiene el mayor contenido relativo de minerales de Ag y Au. En general, las asociaciones de metales preciosos (fases I, IIB y III) se inician con sulfosales de Cu-Ag y/o sufosales de Pb-Ag y terminan con sulfosales de Ag. Los principales minerales portadores de Ag del depósito son proustita-pirargirita y tetredritasagentíferas. Existe una estrecha relación entre estasúltimas y el electrum.

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13

Greenhoot, Christopher A. "Geology of the metates gold-silver deposit, Durango, Mexico." Thesis, The University of Arizona, 2000. http://hdl.handle.net/10150/566662.

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Trotman, Richard B. "Geology of the Storm gold-silver deposit, Elko County, Nevada." abstract and full text PDF (UNR users only), 2009. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1464559.

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15

Poulter, Neil. "Novel antimicrobial plasma deposited films." Thesis, University of Bath, 2010. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.518294.

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Bacterial infection is a growing concern in hospital and community settings, where the issue of biofilms is a major problem. Most current methods of preventing microbial attachment and biofilm formation are limited due to application, process or inherent flaws. It was proposed that thin films containing an organometallic element could be deposited using plasma, a quick, clean surface modification technique; to create antimicrobial films which could then be applied to a range of substrates.
Several novel antimicrobial monomer systems were synthesised and characterised based on silver, copper and zinc as the active constituent with phosphines, phosphites, maleimide and a novel Schiff base among the ligand systems. All monomers were found to greatly inhibit the growth of P. aeruginosa and S. aureus in solution and on solid media. Successful monomers were deposited onto suitable substrates (glass, gold, plastics, non-woven polypropylene) using continuous wave and pulse plasma, with the films characterised and low levels of active metal found in analysis using XPS and SIMS. Films were tested against solutions of pathogenic bacteria using a number of traditional and modern microbiological techniques and found to inhibit growth under a range of conditions, potentially due to the synergistic action of metal and ligand on bacterial cells. Effective control of bacteria was exhibited at times varying from 1h to 24h+. Highly volatile compounds were produced which allowed quick deposition of plasma films, which showed excellent activity against bacteria (99.9%+ growth reduction), indicating viability for potential application. All films tested showed no inhibition or toxicity to eukaryotic cells.

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Forman, Katherine Crawford. "Baseline geophysics over North Silver Bell ore deposit, Pima County, Arizona." Thesis, The University of Arizona, 1994. http://hdl.handle.net/10150/558234.

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McClenaghan, Lindsay. "Geology and genesis of the Newton bulk-tonnage gold-silver deposit central British Columbia." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/44008.

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The Newton Au-Ag deposit is located in the Chilcotin Plateau of central British Columbia, Canada. The deposit lacks vein textures typical of magmatic-hydrothermal deposits and its genesis is poorly understood. Investigations focused on drill core logging, petrography, short wave infrared spectroscopy, X-ray diffraction, lithogeochemistry and stable isotopic analyses. The mineralization is hosted within Late Cretaceous age felsic volcanic rocks (U-Pb age of 72.1 ±0.6 Ma). These rocks are interbedded with an intra-arc sedimentary rock sequence that overlies a mafic rock sequence. Porphyritic dykes of felsic to intermediate composition intrude this stratigraphy. The quartz feldspar porphyry yielded a U-Pb age of 70.9±0.5 Ma. Re-Os dating of molybdenite yields an age of 72.1±0.3 Ma and a minimum age for mineralization. The mineralization is stratabound and characterized by pervasive quartz-sericite alteration and disseminated open-space filling sulfides providing strong evidence that the felsic volcanic rocks had high permeability relative to adjacent lithologies. Gold-silver mineralization is associated with two sulfide assemblages 1) pyrite-dominant (pyrite-arsenopyrite) and 2) marcasite–base metal dominant (marcasite-pyrite-chalcopyrite-sphalerite) and rare polymetallic (pyrite-chalcopyrite-sphalerite-arsenopyrite) veins. Siderite has replaced marcasite and chalcopyrite. Variations in Zn-Ag concentrations define a paleothermal gradient that developed in the hydrothermal system. The poorly mineralized felsic porphyry stocks and dykes have quartz-sericite-pyrite-carbonate-kaolinite alteration and minor quartz-calcite-pyrite-molybdenite veinlets. The mafic rocks have propylitic alteration (chlorite-epidote-pyrite-calcite-albite-magnetite). Whole rock lithogeochemistry suggests a calc-alkaline magmatic affinity for the felsic volcanic rocks and the felsic porphyritic intrusions. Alteration intensity is indicated by relative addition of SiO₂, K, C, Fe and removal of Ca and Na. Major rock types show distinct Y-Zr ratios. Hydrothermal fluids in equilibrium with sericite have δ¹⁸O values from 2.5 to 6.8‰ and δD values from -63 to -46.5‰ suggesting a magmatic fluid source that intermixed with meteoric waters. Sulfides have δ³⁴S values from -1.1 to 3.5‰ that indicate a magmatic origin for the sulfur. The results suggest that Newton is a disseminated strata-bound intermediate-sulfidation type epithermal deposit. The Newton deposit is comparable to the Capoose and Blackwater deposits but lacks garnet alteration. The felsic volcanic host rocks at Newton are contemporaneous with the youngest stratigraphy of the Kasalka Group rhyolites (68-71Ma).

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Bradford, John Allan. "Geology and genesis of the midway silver-lead-zinc deposit, north-central British Columbia." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/27398.

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The Midway Ag-Pb-Zn manto deposit is hosted in Middle Devonian McDame Group limestones of the Cassiar Terrane, a displaced segment of the North American miogeocline. In the map area (1040/16), platformal carbonates and siliciclastics of Cambrian to Devonian age are unconformably overlain by Devono-Mississipian basinal sediments, including exhalites (Earn Group). These are structurally overlain, above a flat lying decollement, by Upper Paleozoic marginal basin sediments, basaltic volcanics, intrusives and ultramafites (Sylvester allochthon). The decollement represents the boundary between Cassiar Terrane and Slide Mountain Terrane in the map area. Jurassic contraction of the North American margin and emplacement of the Sylvester allochthon produced southeasterly trending major and minor structures. Cretaceous - Tertiary extension, linked to transcurrent motion along the Kechika and related faults, produced the north trending high angle Tootsee River fault zone, which divides the map area. Two intrusive suites, of mid-Cretaceous (100 Ma) and Late Cretaceous (70 Ma) ages, are documented by K-Ar dating. The Late Cretaceous episode is evidenced by large sericite - pyrite alteration zones southeast of Midway, but only a few felsic porphyry dykes are exposed at current erosion levels. High angle faults in the Tootsee River fault zone confined intrusion driven hydrothermal fluid migration up plunge from an intrusive centre about 2 kilometres southeast of Midway. Fluids were ponded in a southeasterly plunging antiformal trap, and massive sulphides deposited in zones of pre-existing karst breccia porosity beneath a relatively impermeable shale cap. Fe and Cu rich pyrrhotitic assemblages occur at greater depth toward the intrusive centre, with sulphosalt rich pyritic assemblages at shallower depths to the north. Immiscible aqueous - carbonic liquid and vapour were trapped in quartz deposited with sulphides at 300-340OC. Later lower temperature inclusions record the progressive loss of CH₄ and CO₂ from the system. Salinities were about 7-10 weight % NaCl equivalent. Sulphur isotopes of sulphides span a narrow range, indicating a well mixed reservoir and H₂S dominated environment. Both sedimentary and igneous sources are indicated. Oxygen isotopes of carbonates demonstrate large ¹⁸O depletions due to extensive meteoric water interaction. In a regional context (Rancheria silver district), Midway lead isotopes suggest mixing of upper crustal lead from country rocks with intrusion derived lower crustal lead. Cassiar Terrane epigenetic deposits are distinguished from epigenetic deposits of Slide Mountain Terrane, which have significant mantle lead, consistent with derivation from oceanic and arc host rock assemblages.
Science, Faculty of
Earth, Ocean and Atmospheric Sciences, Department of
Graduate

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Cloutier, Maxime, and Maxime Cloutier. "Silver-containing diamond-like carbon deposited by plasma as versatile antibacterial coatings." Doctoral thesis, Université Laval, 2017. http://hdl.handle.net/20.500.11794/27974.

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Les infections associées au milieu hospitalier demeurent une cause majeure de mortalité et de morbidité dans le monde, malgré plusieurs décennies dédiées à promouvoir une meilleure surveillance et des méthodes de désinfection plus complètes. La capacité des bactéries pathogènes à survivre sur des substrats solides a été identifiée comme un facteur clé de la pathogenèse de ces infections, en multipliant les sources de transmission et de contamination. Au niveau de la recherche, cette situation s’est récemment traduite par un intérêt marqué pour le développement de revêtements antibactériens novateurs pouvant constituer une ligne de défense complémentaire contre la colonisation bactérienne de surfaces, pourvu qu’ils puissent résister à l’environnement rigoureux des établissements de santé. Dans cette thèse, nous avons émis l'hypothèse qu'un revêtement antibactérien avec une stabilité supérieure pouvait être déposé en utilisant un procédé plasma modulable, de sorte que les propriétés du revêtement résultant pourraient être adaptées aux exigences de différentes situations ou applications. Par conséquent, des revêtements nanocomposites de carbone amorphe adamantin contenant de l'argent (Ag-DLC) ont été développés et étudiés comme plate-forme polyvalente pour des surfaces antibactériennes. L’intérêt de ce matériau réside dans la combinaison des excellentes propriétés mécaniques, de la résistance à l'usure et de l'inertie chimique du carbone amorphe adamantin avec les propriétés antibactériennes à large spectre des nanomatériaux d'argent au sein d’un même revêtement déposé par plasma. Ce travail a d'abord identifié les défis de conception spécifiquement associés au développement de revêtements antibactériens pour le milieu hospitalier. Des analyses approfondies des revêtements Ag-DLC ont ensuite démontré une bonne efficacité antibactérienne in vitro ainsi qu’une stabilité des propriétés, de la structure et de l’état chimique des revêtements dans le temps. L'étendue de la polyvalence des revêtements Ag-DLC a été évaluée au travers de l’identification des mécanismes de croissance principaux, permettant d’obtenir des informations essentielles sur la façon dont les propriétés des films, telles que la dureté, la teneur et la distribution d’argent, pouvaient être contrôlées en ajustant des paramètres spécifiques du dépôt plasma. De plus, un traitement de surface in situ a été développé pour surmonter les problèmes de délamination et a montré la capacité de favoriser l'adhérence de revêtements DLC sur des substrats métalliques. Dans l'ensemble, cette étude a mis en évidence l'importance de la stabilité dans l'application des revêtements antibactériens et a démontré le vaste potentiel des procédés plasma pour le dépôt de revêtements antibactériens stables avec des propriétés adaptables.
Les infections associées au milieu hospitalier demeurent une cause majeure de mortalité et de morbidité dans le monde, malgré plusieurs décennies dédiées à promouvoir une meilleure surveillance et des méthodes de désinfection plus complètes. La capacité des bactéries pathogènes à survivre sur des substrats solides a été identifiée comme un facteur clé de la pathogenèse de ces infections, en multipliant les sources de transmission et de contamination. Au niveau de la recherche, cette situation s’est récemment traduite par un intérêt marqué pour le développement de revêtements antibactériens novateurs pouvant constituer une ligne de défense complémentaire contre la colonisation bactérienne de surfaces, pourvu qu’ils puissent résister à l’environnement rigoureux des établissements de santé. Dans cette thèse, nous avons émis l'hypothèse qu'un revêtement antibactérien avec une stabilité supérieure pouvait être déposé en utilisant un procédé plasma modulable, de sorte que les propriétés du revêtement résultant pourraient être adaptées aux exigences de différentes situations ou applications. Par conséquent, des revêtements nanocomposites de carbone amorphe adamantin contenant de l'argent (Ag-DLC) ont été développés et étudiés comme plate-forme polyvalente pour des surfaces antibactériennes. L’intérêt de ce matériau réside dans la combinaison des excellentes propriétés mécaniques, de la résistance à l'usure et de l'inertie chimique du carbone amorphe adamantin avec les propriétés antibactériennes à large spectre des nanomatériaux d'argent au sein d’un même revêtement déposé par plasma. Ce travail a d'abord identifié les défis de conception spécifiquement associés au développement de revêtements antibactériens pour le milieu hospitalier. Des analyses approfondies des revêtements Ag-DLC ont ensuite démontré une bonne efficacité antibactérienne in vitro ainsi qu’une stabilité des propriétés, de la structure et de l’état chimique des revêtements dans le temps. L'étendue de la polyvalence des revêtements Ag-DLC a été évaluée au travers de l’identification des mécanismes de croissance principaux, permettant d’obtenir des informations essentielles sur la façon dont les propriétés des films, telles que la dureté, la teneur et la distribution d’argent, pouvaient être contrôlées en ajustant des paramètres spécifiques du dépôt plasma. De plus, un traitement de surface in situ a été développé pour surmonter les problèmes de délamination et a montré la capacité de favoriser l'adhérence de revêtements DLC sur des substrats métalliques. Dans l'ensemble, cette étude a mis en évidence l'importance de la stabilité dans l'application des revêtements antibactériens et a démontré le vaste potentiel des procédés plasma pour le dépôt de revêtements antibactériens stables avec des propriétés adaptables.
Healthcare-associated infections remain a major cause of mortality and morbidity worldwide, with a substantial financial burden on society, despite decades of monitoring and disinfection efforts. The ability of pathogenic bacteria to survive on solid substrates has emerged as a key contributing factor in the pathogenesis of these infections by multiplying the sources of transmission and contamination. This has prompted investigations into the development of innovative antibacterial coatings, which could provide a complementary barrier against bacterial colonization of surfaces provided that they can withstand the harsh operating environment of healthcare facilities. In this thesis, we hypothesized that an antibacterial coating with superior stability could be deposited using a tailorable plasma process, so that the resulting coatings’ properties could be adapted to match the requirements of different situations or applications. Therefore, silver-containing diamond-like carbon (Ag-DLC) nanocomposite coatings were developed and investigated as a versatile platform material for antibacterial surfaces. The interest of this material lies in the combination of the excellent mechanical properties, wear-resistance and chemical inertness of diamond-like carbon with the broad-spectrum antibacterial properties of silver nanomaterials in a single, plasma-deposited coating. This work first identified the specific design challenges associated with the development of antibacterial coatings for healthcare environments. Thorough investigations of Ag-DLC coatings then revealed good antibacterial efficacy in vitro as well as stability of the coatings’ properties, structure, and chemistry over time. The extent of the tailorability of Ag-DLC coatings was also assessed through the identification of the main growth mechanisms, providing insights on how the film’s properties, such as the hardness, silver content, and silver distribution, could be controlled by adjusting specific plasma deposition parameters. Furthermore, an in situ interface plasma treatment was developed to overcome delamination issues and showed the ability to promote the adhesion of high stress DLC coatings on metallic substrates. Overall, this study highlighted the importance of stability in the application of antibacterial coatings and demonstrated the vast potential of plasma processes for the deposition of stable antibacterial coatings with tunable properties.
Healthcare-associated infections remain a major cause of mortality and morbidity worldwide, with a substantial financial burden on society, despite decades of monitoring and disinfection efforts. The ability of pathogenic bacteria to survive on solid substrates has emerged as a key contributing factor in the pathogenesis of these infections by multiplying the sources of transmission and contamination. This has prompted investigations into the development of innovative antibacterial coatings, which could provide a complementary barrier against bacterial colonization of surfaces provided that they can withstand the harsh operating environment of healthcare facilities. In this thesis, we hypothesized that an antibacterial coating with superior stability could be deposited using a tailorable plasma process, so that the resulting coatings’ properties could be adapted to match the requirements of different situations or applications. Therefore, silver-containing diamond-like carbon (Ag-DLC) nanocomposite coatings were developed and investigated as a versatile platform material for antibacterial surfaces. The interest of this material lies in the combination of the excellent mechanical properties, wear-resistance and chemical inertness of diamond-like carbon with the broad-spectrum antibacterial properties of silver nanomaterials in a single, plasma-deposited coating. This work first identified the specific design challenges associated with the development of antibacterial coatings for healthcare environments. Thorough investigations of Ag-DLC coatings then revealed good antibacterial efficacy in vitro as well as stability of the coatings’ properties, structure, and chemistry over time. The extent of the tailorability of Ag-DLC coatings was also assessed through the identification of the main growth mechanisms, providing insights on how the film’s properties, such as the hardness, silver content, and silver distribution, could be controlled by adjusting specific plasma deposition parameters. Furthermore, an in situ interface plasma treatment was developed to overcome delamination issues and showed the ability to promote the adhesion of high stress DLC coatings on metallic substrates. Overall, this study highlighted the importance of stability in the application of antibacterial coatings and demonstrated the vast potential of plasma processes for the deposition of stable antibacterial coatings with tunable properties.

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20

Wallier, Stefan. "The geology and evolution of the Manantial Espejo epithermal silver(-gold) deposit, Deseado Massif, Argentina." Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/17439.

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Quartz-adularia epithermal veins record the interplay between magmatism, tectonism, and derivative geothermal systems. At Manantial Espejo, southern Argentina, such veins form a Ag(-Au) deposit with a proven and probable reserve of 38.5 Moz Ag and 0.55 Moz Au. The district located in the Deseado Massif is part of the Middle to Late Jurassic Chon Aike Province, a large bimodal igneous province dominated by silicic volcanic rocks that was formed in association with the Gondwana break-up. The district stratigraphy consists of a more then 400 m thick andesitic to rhyolitic volcanic succession formed between 162 and 157 Ma. The precious metal veins post-date the volcanic host rocks and formed contemporaneously with normal faults at 154 ± 1 Ma. Mineralized veins are Ag-rich examples of a low- to intermediate-sulfidation epithermal deposit. In the Maria Vein, the major orebody of the district, six hydrothermal stages are identified, but only stages 1 and 4 contributed significantly metal. The distribution of the hydrothermal stages along the vein is primarily controlled by fault formation and records the growth and linkage of vein segments to form an integrated curviplanar vein. Alteration mineral zoning about the Maria Vein with proximal adularia and distal illite and illite-smectite assemblages shows higher temperature mineral assemblages extending over a broader halo and to shallower levels along a high-grade vein segment where compared to a low-grade segment. The dominant changes in whole-rock alteration geochemistry toward the Maria Vein are the gain of K and the loss of Na, Ca, and Mg. Precious metals, base metals, and pathfinder elements have typically increasing concentrations toward the vein. Boiling was the dominant depositional process and metal ratios in veins reflect the abundance of dissolved metals in solution. Barren quartz with abundant boiling textures was formed by low-salinity fluids of temperatures between 230° and 270°C. Mineralizing fluids had lower temperatures, but salinities between 4 and 10 wt % NaC1 equiv. Lead isotopic constraints indicate a mostly common source for Pb in volcanic rocks of the Chon Aike Formation and Pb in hydrothermal sulfides, or that the Pb in the hydrothermal veins was derived from the Chon Aike Formation.

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Burtt, Martin David. "Geology of the B-baseline zone, Walton barium-copper-lead-zinc-silver deposit, Nova Scotia." Thesis, University of Ottawa (Canada), 1995. http://hdl.handle.net/10393/10065.

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The Walton Ba-Cu-Pb-Zn-Ag deposit, Nova Scotia, is hosted by Visean-aged carbonate rocks of the Macumber Formation and its associated breccia. The Macumber Formation in the Walton area is divided into two units, the lower Macumber, a laminated carbonate 30-40$\sp\prime$ thick and the upper Macumber, a synsedimentary slump breccia that forms two mounds up to 70$\sp\prime$ thick. Outside the immediate mine area the carbonate is either limestone or dolostone; the Macumber Formation surrounding the deposit has been altered by hydrothermal fluids to manganiferous siderite. Based on barite and metal content two main ore types were defined. Type I comprises barite and variable sulphide contents, whereas Type II comprises only sulphides. Type I ore forms a stratiform sheet which straddles the upper Macumber/lower Macumber contact and contains lenses of Pb-rich and Cu-rich ore. Type II ore is most commonly associated with the upper Macumber mounds where it forms a large pod which cuts the Type I ore zone. The host stratigraphy is presently steeply dipping and faulted, both of which are considered to be post-ore events. The Walton deposit probably formed when uplift of the Cobequid Highlands in the late Namurian initiated gravity-driven flow of basinal fluids through a basal aquifer within the Horton Bluff Formation. The hot fluids flowed south toward the basin margin and leached salts and metals from the aquifer. In the Walton area these fluids were released, along faults, into the overlying Macumber carbonate and synsedimentary carbonate breccia, replacing them initially with manganiferous siderite. (Abstract shortened by UMI.)

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Johansson, Simon. "Ore mineralogy and silver distribution at the Rävliden N volcanogenic massive sulphide deposit, Skellefte district, Sweden." Thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-66264.

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The Rävliden North deposit (Rävliden N) is a volcanogenic massive sulphide (VMS) deposit in the western part of the Skellefte district, northern Sweden. The district is one of Sweden’s major metallogenic provinces with a significant amount of VMS deposits. The Rävliden N deposit, discovered in 2011, contains copper, zinc, lead, silver and subordinate gold and occurs close to the largest VMS deposit in the district, the Kristineberg deposit, which has been mined for more than 70 years. The purpose of this master thesis is to study the composition, mineralogy and paragenetic relationships in different types of sulphide mineralization from the Rävliden N deposit. Emphasis is placed on characterizing the distribution and paragenetic relationships of silver-bearing minerals. The methods include core logging, sampling and mineralogical studies through light optical microscopy (LOM), scanning electron microscopy (SEM) and quantitative evaluation of mineralogy by scanning electron microscopy (QEMSCAN). Lastly, electron microprobe analysis (EMPA) was used to determine the chemical composition of silver-bearing minerals and sulphides. Mineralization types studied include 1: the main massive to semi-massive sulphide mineralization, 2: stratigraphically underlying stringer mineralization and 3: local, vein- and/or fault-hosted silver-rich mineralization in the stratigraphic hanging wall. The massive to semi-massive sulphide mineralization is dominated by sphalerite with lesser galena and pyrrhotite. In contrast, the stringer mineralization is dominated by chalcopyrite and pyrrhotite. The major minerals show evidence of a coeval formation and textural as well as structural evidence suggest that ductile deformation has affected the mineralization types. Notable evidence includes ball-ore textures, accumulation of minerals in pressure shadows and brittle fracturing of competent arsenopyrite and pyrite porphyroblasts and infilling by more incompetent sulphide minerals. The silver-bearing minerals identified are commonly spatially associated with galena and the major species is freibergite ((Ag,Cu,Fe)12(Sb,As)4S13), which also occur as inclusions in chalcopyrite mainly in the stringer mineralization. The stringer mineralization also contains notable amounts of hessite (Ag2Te). Notably, galena, pyrrhotite, freibergite and other sulphosalt minerals are commonly accumulated in pressure shadows near host rock fragments in the massive to semi-massive sulphide mineralization. The only gold-bearing mineral identified in this study is electrum (Au, Ag) in the stringer mineralization. The hanging wall mineralization locally comprises faulted and/or sheared massive sulphide mineralization which is compositionally similar to the main massive to semi-massive sulphide mineralization, besides a significantly higher content of freibergite. However, parts of the hanging wall mineralization are entirely dominated by sulphides and sulphosalts of silver, such as pyrargyrite (Ag3SbS3), pyrostilpnite (Ag3SbS3), argentopyrite (AgFe2S4), sternbergite (AgFe2S3) and stephanite (Ag5SbS4). These occur in structurally late settings, which along with consideration of their temperature stabilities suggest a late origin. Since the silver-bearing minerals in the massive to semi-massive sulphide mineralization and the two varieties of hanging wall mineralization contains the same metals, the mineralization in the hanging wall may have formed by late-stage remobilization of ore components from the underlying Rävliden N deposit. This negates the need for multiple mineralization events to explain the local silver-enriched zones in the hanging wall. The paragenetically late mineralization types contains high content of Ag-bearing minerals in relation to base metal sulphides. This suggests that remobilisation processes were important for locally upgrading the Ag-content.

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Sheets, Ronald Wynn. "Geology and mineralization in the vicinity of the Morning Star precious-metal deposit of the Ivanpah Mountains, San Bernardino County, California." Diss., This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-08272007-163631/.

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Peterson, Sarah M. "Influence of scale, geometry, and microstructure on the electrical properties of chemically deposited thin silver films /." Connect to title online (ProQuest), 2007. http://proquest.umi.com/pqdweb?did=1453183211&sid=2&Fmt=2&clientId=11238&RQT=309&VName=PQD.

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Thesis (Ph. D.)--University of Oregon, 2007.
Typescript. Includes vita and abstract. Includes bibliographical references (leaves 95-101). Also available online in ProQuest, free to University of Oregon users.

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GUY, ANITA LOUISE. "THE EFFECT OF UNDERPOTENTIALLY DEPOSITED LEAD THIN FILMS ON SURFACE ENHANCED RAMAN SCATTERING AT SILVER ELECTRODES." Diss., The University of Arizona, 1986. http://hdl.handle.net/10150/183882.

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This dissertation details the effect of underpotentially deposited (UPD) Pb on the surface enhanced Raman scattering (SERS) ability of roughened polycrystalline Ag electrodes. The deposition of monolayer and submonolayer amounts of Pb results in a quenching of the SERS response for pyridine and Cl⁻ adsorbed at Ag electrodes. Various factors which may contribute to the loss of SERS intensity are investigated. The most significant factors include changes in surface roughness features brought about by Pb UPD, changes in surface electronic properties of Pb-modified Ag and changes in a chemical contribution to surface enhancement. Possible changes in surface roughness properties of the Ag electrode due to Pb deposition are examined using scanning electron microscopy (SEM) and SERS reversibility studies. SEMs of roughened Ag electrodes before and after Pb monolayer deposition show no significant change in the morphology of the larger roughness features. However, the deposition and stripping of 60 - 70% of a Pb monolayer results in a loss of ca. 50% of the original SERS intensity for both adsorbate bands. This irreversible loss of SERS intensity is attributed to the destruction of atomic scale roughness (ASR). These results suggest that ca. 50% of the observed SERS response arises from a mechanism involving ASR. In addition, the destruction of ASR is shown to be largely responsible for the quenching of SERS at higher Pb coverages. The morphology of the SERS quenching profiles at lower Pb coverages for pyridine and Cl⁻ varies as a function of excitation wavelength. Experimental quenching profiles are compared with theoretical quenching profiles based on an electromagnetic contribution to SERS. Theoretical quenching profiles are calculated using a model for electromagnetic enhancement at a overlayer-covered ellipsoids proposed by Murray. The experimental results for both adsorbates are in agreement with the theoretical predictions for laser excitation in the blue. Experimental results in the green and red wavelength regions are best explained in terms of photoassisted charge-transfer mechanisms for surface enhancement.

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Peterson, Sarah M. 1975. "Influence of scale, geometry, and microstructure on the electrical properties of chemically deposited thin silver films." Thesis, University of Oregon, 2007. http://hdl.handle.net/1794/8453.

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xv, 101 p. ; ill. (some col.) A print copy of this title is available through the UO Libraries under the call number: KNIGHT QC176.84.E5 P47 2007
Silver films with nanoscale to mesoscale thicknesses were produced by chemical reduction onto silica substrates and their physical and electrical properties were investigated and characterized. The method of silver deposition was developed in the context of this research and uses a single step reaction to produce consistent silver films on both flat silica coverslips and silica nanospheres of 250-1000 nm. Both the structure and the electrical properties of the silver films are found to differ significantly from those produced by vacuum deposition. Chemically deposited (CD) silver is not uniformly smooth, but rather is granular and porous with a network-like structure. By quantitatively accounting for the differences in scale, geometry, and microstructure of the CD films, it is found that the same models used to describe the resistivity of vacuum deposited films may be applied to CD films. A critical point in the analysis that allows this relation involves the definition of a geometric parameter, g, which replaces the thickness, t, as the critical length that influences the electrical properties of the film. The temperature dependent properties of electrical transport were also investigated and related to the microstructure of the CD films. A detailed characterization of CD silver as shells on silica spheres is also presented including physical and optical properties. In spite of the rough and porous morphology of the shells, the plasmon resonance of the core-shell structure is determined by the overall spherical shell structure and is tunable through variations in the shell thickness. Preliminary investigations into the electrical transport properties of aggregates of silver coated spheres suggest similarities in the influence scale, geometry, and microstructure to silver films on flat substrates. The aggregates of shells also exhibit pressure related resistance behavior due to the composite structure.
Adviser: Miriam Deutsch

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27

Cline, Jean Schroeder 1948. "The sixteen-to-one epithermal silver-gold deposit, Esmeralda County, Nevada: a wall rock alteration and fluid inclusion study." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/558052.

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28

McDonald, Bruce Walter Robert. "Geology and genesis of the Mount Skukum tertiary epithermal gold-silver vein deposit, southwestern Yukon Territory (NTS 105D SW)." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26448.

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The Tertiary Mt. Skukum gold - silver epithermal vein deposit occurs 65 km southwest of Whitehorse in the Yukon Territory. Veins are hosted by a sequence of nearly flat-lying Eocene Skukum Group andesitic volcanic rocks of the Mt. Skukum Volcanic Complex, part of the Sloko Volcanic Province which unconformably overlies these intrusive complexes as well as metamorphic rocks of the Yukon Group. Major known mineralized zones occur within a regional halo of propylitic alteration centered on a fault-bounded graben within Main Cirque in the southwestern corner of the Mt. Skukum Volcanic Complex. Each zone consists of steeply-dipping quartz-carbonate-sericite veins associated with major faults and rhyolite dykes which bound blocks of the graben. Precious metals occur as electrum and native silver as fine grains averaging 15 to 20 microns and locaIly exceeding 1 mm across, in veins containing only trace amounts of sulphides. Fluid inclusions indicate that vein minerals were deposited from hydrothermal fluids averaging 313°C with an average salinity of 0.7 weight percent NaCl equivalent. Primary inclusions show that depositional fluids existed under two pressure regimes; one close to hydrostatic, the other approaching lithostatic. Both reflect depths of deposition of about 470 m below paleosurface. Variable fluid pressures reflecting similar depths of deposition combined with variable liquid to vapour ratios in primary inclusions as well as abundant textural evidence of hydrothermal brecciation indicate that boiling was common during mineralization. Oxygen and carbon isotope composition of minerals in the deposit and surrounding wall rocks indicate that depositional fluids were meteoric in origin with no contribution from magmatic sources. Large depletions in 0¹⁸ content of andesitic rocks in the deposit area indicate a minimum water rock ratio over the life of the deposit of 0.81:1. Precious metals at the Mt. Skukum deposit were emplaced at relatively low temperature in a near surface environment by a circulating, meteoric water dominated, hydrothermal system driven by a heat source associated with the rhyolite dykes. Gold, leached from andesitic volcanic rocks and metamorphic and granitic rocks was precipitated with quartz and carbonate in permeable conduits such as fault zones, and breccia bodies.
Science, Faculty of
Earth, Ocean and Atmospheric Sciences, Department of
Graduate

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29

Looby, Erin Lynn. "The timing and genesis of the Blackwater gold-silver deposit, central British Columbia : constraints from geology, geochronology and stable isotopes." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/52174.

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The Blackwater Au-Ag deposit of central British Columbia is hosted by a lithic-rich, latite lapilli tuff and felsic volcanic rock sequence. U/Pb zircon geochronology shows that these two volcanic rock sequences are Late-Cretaceous, and were deposited at ca. 73.5 and 73.1 Ma, respectively. These host rocks overlie plagioclase to hornblende porphyritic andesite lava flows, mudstone, chert and conglomerate. A monzonite intruded the western portion of the deposit. Felsic dykes or sills are inferred to have intruded felsic volcanic rocks at ca. 68 Ma. A post-mineralization, dacitic sill intruded contacts between sedimentary rocks and lithic-rich, latite tuffs in the south of the Blackwater deposit at ca. 53 Ma. High temperature (>300⁰C), biotite-sericite-sulfide, actinolite-sulfide and garnet-sulfide assemblages alter rocks at the deposit’s perimeter. Low temperature (250-350⁰C), Au-mineralizing fluids precipitated the early main-stage green sericite-quartz-pyrite and the late main-stage green sericite-chlorite-quartz-base metal sulfide assemblages located in the deposit’s centre. ⁴⁰Ar/³⁹Ar geochronology suggests that high temperature alteration minerals precipitated prior to Au-mineralization, between ~68-64 Ma, and that Au-mineralization took place at ca. 65.6-63.9 Ma. The ⁴⁰Ar/³⁹Ar systematics of biotite were reset at ca. 59 Ma during a thermal event. High temperature, barren alteration is attributed to fluids with stable isotope compositions distinct from those that precipitated low temperature alteration. High temperature alteration minerals are enriched in ¹⁸O relative to primary magmatic waters (δ¹⁸OH₂O = 8.9-12.6‰) and have variable δD values (δD =-93.9 to -66.1‰). This, in conjunction with depleted, sedimentary δ³⁴S values (δ³⁴Smineral =-17.7 to -7.7‰) suggests a combination of exchanged meteoric waters, sedimentary formation and/or magmatic fluid sources. A component of magmatic fluids ± evolved meteoric fluids is inferred for low temperature, Au mineralizing fluids. Calculated stable isotope compositions of fluids in equilibrium with green sericite (δ¹⁸O =6.6 - 7.1‰, δD = -79.2 to -62.9‰) plot within the primary magmatic water field while isotopic compositions of associated sulfides (δ³⁴Smineral =-1.8 - 0.3‰) provide evidence for igneous derived sulfur. Blackwater’s host rocks, tectonic environment, metal signature and alteration match those of an intermediate-sulfidation epithermal system with both low- and intermediate sulfidation state sulfide minerals.
Science, Faculty of
Earth, Ocean and Atmospheric Sciences, Department of
Graduate

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30

Gorgoi, Mihaela. "Electronic Properties of Phthalocyanines Deposited on H-Si(111)." Doctoral thesis, Universitätsbibliothek Chemnitz, 2007. http://nbn-resolving.de/urn:nbn:de:swb:ch1-200700213.

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Im Rahmen dieser Arbeit wurden vier Phthalocyanine untersucht: Metallfreies-Phthalocyanin (H2Pc), Kupferphthalocyanin (CuPc) und Fluor-substituiertes Phthalocyanin (F4CuPc und F16CuPc). Das Ziel dieser Arbeit ist die Charakterisierung der elektronischen und chemischen Eigenschaften der Grenzflächen zwischen diesen Molekülen und Silizium. Die Moleküle wurden durch organische Molekularstrahldeposition (OMBD) im Ultrahochvakuum auf wasserstoffpassivierte Si(111)-Substrate aufgedampft. Oberflächensensitive Messmethoden wie Photoemissionsspektroskopie (PES), Bremsstrahlung Isochromaten Spektroskopie (BIS oder IPES - Inverse Photoemissionsspektroskopie) und Spektroskopie der Röntgen-Absorptions-Feinstruktur (NEXAFS – Near Edge X-Ray Absorption Fine Structure) wurden zur Charakterisierung eingesetzt. Um eine Zuordnung der verschiedenen Komponenten in PES und IPES zu ermöglichen, wurden Methoden der Dichtefunktionaltheorie zur theoretischen Berechnung eingesetzt. Die Energieniveauanpassung an der Grenzfläche zwischen der organischen Schicht und der H-Si-Grenzfläche, sowie die Transportbandlücke von H2Pc, CuPc, F4CuPc und F16CuPc wurden mit Hilfe von PES und IPES bestimmt. Die NEXAFS-Messungen ermöglichten eine genaue Bestimmung der Molekülorientierung relativ zum Substrat. Die Auswertung der Daten zeigte unterschiedliche Molekülorientierungen in dünnen und dicken Filmen. Diese Änderungen wurden mit dem bandverbiegungsähnlichen Verlauf der HOMO-und LUMO-Positionen in Verbindung gebracht. Zusätzlich zu diesem Verhalten wiesen die Grenzflächen auch einen Grenzflächendipol auf, welcher durch die unterschiedlichen Austrittsarbeiten der Kontaktmaterialien hervorgerufen wird. Der Einfluss des Grads der Flouridierung wird durch eine ähnlichen Zunahme der Elektronenaffinität (EA), der Austrittsarbeit (WF) und der Ionisierungsenergie (IE) bestätigt. Die elektronischen Eigenschaften von Metall/organische-Schicht-Grenzflächen und von organischen Schichten unter Sauerstoffeinfluss wurden mit Hilfe von PES und IPES untersucht. Die Ag/Pc Grenzflächen zeigten eine Mischung aus HOMO-LUMO-Verschiebungen und Grenzflächendipolbildung. An den Ag/H2Pc- und Ag/F16CuPc- Grenzflächen wurde ein Ladungstransferkomplex gebildet. Auf der CuPc-Schicht physisorbiert das Ag lediglich und im Fall von F4CuPc wird Ladung zu Ag transferiert, wobei eine andauernde n-Typ-Dotierung an der Grenzfläche erzeugt wird. In Analogie zum Fall der Pc/H-Si Grenzfläche wiesen die Dipole, die hier gefunden wurden, eine lineare Abhängigkeit von EA, WF und IE auf und können durch die Differenz zwischen den Austrittsarbeiten vorausgesagt werden. Das Verhalten der dicken organischen Schichten unter Sauerstoffeinfluss kann in zwei Gruppen eingeteilt werden. Eine Gruppe, bestehend aus H2Pc und F4CuPc, wies nur schwache Wechselwirkung auf und der Sauerstoff physisorbiert auf der Pc-Schicht. Die beiden anderen Moleküle, CuPc und F16CuPc konnten einer Gruppe starker Wechselwirkung zugeordnet werden. CuPc bildet einen Ladungstransferkomplex mit Sauerstoff und auf F16CuPc wird eine polarisierte Schicht gebildet
In the context of this work four Phthalocyanine were studied: Metal-free Phthalocyanine (H2Pc), Copper Phthalocyanine (CuPc) and fluorine-substituted Phthalocyanine (F4CuPc and F16CuPc). The goal of this work is the electronic and chemical characteristics of the interfaces. The molecules were deposited by organic molecular beam deposition (OMBD) in the ultra high vacuum on hydrogen-passivated Si(111)-Substrate. Surface sensitive techniques such as photoemission spectroscopy (PES), bremsstrahlung isochromate spectroscopy (BIS or IPES - inverse photoemission spectroscopy) and near edge X-ray absorption fine structure spectroscopy (NEXAFS) were used for characterisation. Theoretical computations by density functional theory methods were employed, in order to assign different components in PES and IPES. The energy level alignment at the organic/H-Si interface, as well as the transport gap of H2Pc, CuPc, F4CuPc and F16CuPc were determined by PES and IPES. The NEXAFS measurements determine the exact molecular orientation with respect to the substrate. The evaluation of the data showed different molecular orientation in the thin and thick films. This change was correlated with the band bending like behaviours that emerged at these interfaces. In addition to the band bending like behaviour, the interfaces show also an interface dipole which is driven by the work function difference between the contact materials. The influence of the degree of fluorination is confirmed in the similar increase of the EA, WF and IE. The electronic properties of metal/organic layer interfaces and of organic layer under oxygen influence were examined by PES and IPES. The Ag/Pc interfaces show a mixture of HOMO-LUMO shifts and interface dipole formation. A charge transfer complex is formed in the case of Ag/H2Pc and Ag/F16CuPc interfaces. Ag is physisorbed atop the CuPc. Charge transfers from F4CuPc to Ag creating a continuous n-type doping at the interface. Similar to the Pc/H-Si interfaces the interface dipoles found here show a linear dependence on the EA, WF and IE and can be predicted by the difference in the work functions. The data evaluation of oxygen exposed thick films determined two groups of behaviours. The weak interaction group is represented by H2Pc and F4CuPc, Pcs on which oxygen is physisorbed. The strong interaction group contains the other two molecules CuPc and F16CuPc. CuPc forms a charge transfer complex with oxygen and on top of F16CuPc a polarized layer is formed

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31

Colakoglu, Tahir. "The Effects Of Post-annealing Process On The Physical Properties Of Silver-indium-selenium Ternary Semiconductor Thin Films Deposited By Electron Beam Technique." Phd thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/2/12610974/index.pdf.

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Ternary chalcopyrite compounds are the semiconductors with suitable properties to be used as absorber materials in thin film solar cells. AgInSe2 is a promising candidate with its several advantages over the widely used CuInSe2. The purpose of this study was to optimize the physical properties of the Ag-In-Se (AIS) thin films that were deposited by e-beam evaporation of Ag3In5Se9 single crystal powder for solar cell applications by means of post-annealing process under nitrogen atmosphere. The as-grown AIS thin films were annealed at 200, 300 and 400oC and their structural, optical, electrical and photoelectrical properties were examined to observe the effects of post-annealing process. Structural characterization of the films was performed by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) analyses. Optical properties of the films were investigated by optical transmittance measurements. Electrical and photoelectrical properties of the films were examined by temperature dependent conductivity, photoconductivity under different illumination intensities and spectral photoresponse measurements. It was discovered that the annealing of AIS thin films at 200oC resulted in the best physical properties for solar cell applications. The obtained films were polycrystalline with mixed binary and ternary crystalline phases, such as Ag3In5Se9, AgInSe2 and InSe, and showed n-type conductivity with room temperature conductivity value of 2.3x10-6 (Ohm
cm)-1. The band gap energy of the 200oC-annealed films was determined as 1.68 eV from spectral photoresponse measurements. The results of the study revealed that the inadequate Ag incorporation and segregation and/or reevaporation of Se atoms at high annealing temperatures were the major problems encountered in producing single phase polycrystalline AgInSe2 thin films. The required stoichiometry of thin films should be maintained during the growth of the films by means of an alternative deposition procedure and the films should be selenized during post-annealing process.

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32

Engemann, David Christopher [Verfasser], Heinz [Akademischer Betreuer] Hövel, and Thomas [Gutachter] Weis. "Silver clusters deposited into polymers, aerogels and ionic liquids studied with X-ray and optical spectroscopy / David Christopher Engemann. Betreuer: Heinz Hövel. Gutachter: Thomas Weis." Dortmund : Universitätsbibliothek Dortmund, 2014. http://d-nb.info/110828986X/34.

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33

Gilbow, Justin R. "Gold-bearing carbonate, sulfide, and silicate veining in igneous and sedimentary lithologies of the Helen Zone, Cove Deposit, Fish Creek Mountains, Nevada." University of Akron / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=akron1460139388.

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34

Rühl, Meike. "Literatur gewordener Augenblick die Silven des Statius im Kontext literarischer und sozialer Bedingungen von Dichtung." Berlin New York de Gruyter, 2004. http://deposit.d-nb.de/cgi-bin/dokserv?id=2848381&prov=M&dok_var=1&dok_ext=htm.

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35

Skaf, Mira. "Comparaison physico-chimique et des [sic] activités catalytiques dans les réactions d'oxydation entre deux séries de catalyseurs Ag/CeO₂ préparés par imprégnation et dépôt-précipitation." Phd thesis, Université du Littoral Côte d'Opale, 2013. http://tel.archives-ouvertes.fr/tel-00983419.

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La cérine est connue pour être très performant en tant que support, dans le domaine de l'oxydation catalytique. L'ajout de métaux de transitions améliore en général cette activité. Dans ce travail, l'argent a été ajouté sur la cérine. Deux méthodes de préparation ont été utilisées : l'imprégnation (Imp), connue par la formation de particules de tailles différentes sur la surface du support, et le dépôt-précipitation (DP) qui conduit en général à la formation de nanoparticules dispersées sur la surface et dans la masse du support. Deux séries de catalyseurs x%Ag/CeO₂(Imp) et x%Ag/CeO₂(DP) où x est le pourcentage massique de l'argent par rapport à la cérine, ont été préparés dans le but de comparer leurs propriétés physico-chimiques. Ensuite leurs activités catalytiques dans les réactions d'oxydation. Les catalyseurs ont été caractérisés par différentes techniques telles que la BET, la DRX, la RPE, l'ATD-ATG, la SPX, l'UV et la RTP. Dans les deux séries de catalyseurs, la DRX a montré que des particules de Ag⁰ ont été obtenues pour les fortes teneurs en argent ; ces particules sont plus grosses dans les imprégnés que dans les (DP). La présence des nanoparticules dans les deux séries de solides a été aussi confirmée par l'UV (résonance plasmonique). Ces nanoparticules sont de formes sphériques dans les (DP) et mi-sphériques, ou déformées, dans les (Imp). Trois états d'oxydation : Ag⁰, Ag⁺ et Ag²⁺ ont été identifiés dans les imprégnés et seulement deux : Ag⁰ et Ag⁺ dans les DP. La formation des ions Ag²⁺ semble être due à la présence de AgNO₃ sur la cérine au cours de la calcination du solide, ce qui était le cas pour les imprégnés et non pour les DP. De plus, les deux isotopes ¹⁰⁷Ag²⁺ et ¹⁰⁹Ag²⁺ ont été mis en évidence par la technique de la RPE ; ce résultat est considéré comme original et primordial. Par la suite, les deux séries de catalyseurs ont été testés dans les réacctions d'oxydations catalytique du propène, du monoxyde de carbone et du noir de carbone. Le résultat inattendu dans ce travail c'est que, contrairement à la bibliographie, les catalyseurs imprégnés étaient plus actifs que les (DP) pour les trois réactions. La performance catalytique des imprégnés a été reliée à la présence des espèces Ag²⁺ qui sont absents dans les DP. Autrement exprimé à la présence de trois couples redox Ag²⁺/ Ag⁺, Ag²⁺/ Ag⁰ et Ag⁺/ Ag⁰ dans le cas des solides (Imp), pour seulement un couple redox Ag⁺/ Ag⁰ dans le cas des solides (DP). Une présence adéquate dans les rapports de concentrations de ces trois couples redox dans le catalyseur 10%Ag/CeO₂(Imp) a rendu ce dernier le plus performant comparé aux autres de la même série.

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36

Szczepaniak, Renata. "Der phonologisch-typologische Wandel des Deutschen von einer Silben- zu einer Wortsprache." Berlin New York de Gruyter, 2005. http://deposit.d-nb.de/cgi-bin/dokserv?id=2909227&prov=M&dok_var=1&dok_ext=htm.

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37

Peyroux, Magali. "Les dépôts d’objets pariétaux des grottes ornées au Paléolithique supérieur : gestes, comportements symboliques, cultures." Thesis, Bordeaux 1, 2012. http://www.theses.fr/2012BOR14546/document.

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Les grottes sont un environnement particulier aux propriétés géophysiques singulières. C’est un milieu qui offre une conservation exceptionnelle et dans lequel s’inscrit, dans la matrice minérale, la marque du moindre geste qui y est réalisé. Assidument fréquentées au Paléolithique supérieur, de nombreuses cavités renferment des témoignages variés du passage des hommes. L’art pariétal est un des témoins, parfois spectaculaire, de cette fréquentation. D’autres vestiges (marques, objets, aménagements…) y sont aussi observables. Souvent moins visibles, moins spectaculaires car faisant entrer en jeu des éléments plus communs, l’intérêt de ces vestiges, dans la compréhension des comportements préhistoriques, a été reconnu tardivement dans l’histoire de la discipline. Parmi ces diverses traces d’activités humaines, et faisant suite aux travaux initiateurs sur le sujet (Bégouën et Clottes, 1981 ; Clottes 2007 et 2009), nous nous intéressons ici aux dépôts d’objets en paroi. Aucune étude approfondie et croisée à grande échelle de ce phénomène n’avait été conduite jusqu’ici. Les différentes matérialisations de ces gestes de dépôts, leurs constituants fondamentaux, les cultures et les territoires concernés ainsi que l’approfondissement de la connaissance des comportements humains en grottes ornées au travers de l’étude de ces gestes ont été les principaux axes de notre recherche.Nous avons ainsi identifié la présence de ces gestes de dépôts dans une quarantaine de sites ornés répartis sur l’espace franco-cantabrique durant tout le Paléolithique supérieur. Nous avons essentiellement basé la construction de notre méthode d’étude et notre analyse sur l’étude exhaustive et contextualisée de ces dépôts dans six sites français : Blanchard, Foissac, Gargas inférieure, Gargas supérieure, Le Mammouth et Le Pigeonnier. La priorité était pour nous de proposer une lecture interprétative des comportements à l’origine de ces dépôts. La matière dure animale (à l’état de fragments), et dans une moindre mesure le silex et l’ocre, sont les éléments essentiellement constitutifs de ces dépôts. Les résultats montrent que ces derniers sont omniprésents dans les grottes ornées. Ils ne sont cependant pas tous en tout point comparable. Nous avons pu mettre en évidence différentes catégories de gestes de dépôts. La plupart sont intentionnels mais sous-tendus par des motivations distinctes (symbolique, pragmatique, personnelle…). Nous avons identifié quatre pratiques symboliques où le dépôt est un medium permettant une connexion (« reliance ») avec l’Invisible par l’intermédiaire de la paroi-réceptacle.Ces pratiques (très fréquemment observées au Magdalénien et au Gravettien) sont des comportements symboliques fondamentaux qui motivent la fréquentation des cavités par ces populations préhistoriques durant tout le Paléolithique supérieur. Elles sont intimement reliées aux modes de vie, aux traditions culturelles et à la cosmogonie des sociétés préhistoriques. Ces pratiques préhistoriques peuvent être envisagées selon l’idée d’une possible affiliation à certains des grands universaux qui participent du fonds commun symbolique, et même spirituel, de l’humanité
Caves are a particular environment with singular geophysics properties. It is an environment which offers an exceptional preservation and in which registers, in the mineral matrix, the mark of the slightest gesture which is realized there. Assidument frequented in the upper Palaeolithic, numerous cavities contain varied vestiges of the human passage.The parietal Art is one of the marks, sometimes spectacular, of this frequentation.Other vestiges (marks, objects, arrangements…) are there also observable. Often less visible, less spectacular because using more common elements, the interest of these vestiges, in the understanding of the prehistoric behavior, was late recognized in the history of the discipline. Among these diverse tracks of human activities, and following upon the works initiators on the subject (Bégouën et Clottes, 1981 ; Clottes 2007 et 2009), we are interested here in the deposits of objects in rock face. No in-depth and crossed study on a large scale of this phenomenon had been led up to here.The various realizations of these gestures of deposits, their fundamental constituents, the cultures and the concerned territories as well as the deepening of the knowledge of the human behavior in decorated caves through the study of these gestures were the main axes of our research.We so identified the presence of these gestures of deposits in about forty decorated sites distributed on the French-Catabric space during all the upper Palaeolithic. We essentially based the construction of our method of study and our analysis on the exhaustive and contextualised study of these deposits in six French sites : Blanchard, Foissac, Gargas inférieure, Gargas supérieure, Le Mammouth et Le Pigeonnier. The priority was for us to propose an interpretative reading of the behavior at the origin of these deposits. The animal hard material (in the state of fragments), and to a lesser extent the flint and the ochre, are the essentially constituent elements of these deposits. The results show that these last ones are omnipresent in the decorated caves. They are not however all completely comparable. We were able to bring to light various categories of gestures of deposits. Most are deliberate but underlain by different motivations (symbolic, pragmatic, personal…). We identified four symbolic practices where the deposit is a medium allowing a connection (« reliance ») with the Invisible through the rock face - receptacle.These practices (very frequently observed in the Magdalenian and in the Gravettian) are fundamental symbolic behavior which motivate the frequentation of cavities by these prehistoric populations during all the upper Palaeolithic. They are intimately bound with the lifestyles, with the cultural traditions and with the cosmogony of the prehistoric societies. These prehistoric practices can be envisaged according to the idea of a possible affiliation in some of the big universals which participate in the symbolic common fund, and even spiritual, in the humanity

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38

Beyer, Vera. "Rahmenbestimmungen : Funktionen von Rahmen bei Goya, Velázquez, van Eyck und Degas /." Paderborn : Verlag Wilhelm Fink, 2008. http://deposit.d-nb.de/cgi-bin/dokserv?id=3037654&prov=M&dok_var=1&dok_ext=htm.

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39

"Shear-Zone Hosted Gold and Silver Deposits in the Sierra Cacachilas, Baja California Sur, Mexico." Master's thesis, 2015. http://hdl.handle.net/2286/R.I.34810.

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abstract: The historic Cacachilas mining district is located in Baja California Sur, approximately 20 kilometers east of La Paz, and has a series of gold- and silver-hosted veins, faults, and shear zones within Cretaceous granodioritic plutons. The remote geographic location and past political events within Mexico left the district essentially unexplored after the late 1800s, when the Mexican Revolution began. More recent discovery of gold deposits along the Baja peninsula instigated a renewed interest in mineralization in the Sierra Cacachilas. The area lacks detailed previous geologic data, so this study focused on characterizing the controls of mineralization and the locations of mineralized trends of deposits within the northeastern Sierra Cacachilas, with a goal toward helping assess economic viability of the deposits. I mapped surficial geologic data, such as outcrop locations, alteration assemblages, limonite intensities, and structural measurements. I then synthesized these into geologic maps and cross sections. I combined field data with geochemical assays and structural plots to better characterize individual historic district trends and newly located trends to understand the distribution of mineralization at surface and at depth. Lastly, I synthesized geology of the Sierra Cacachilas with other gold and silver deposits located in the southern Baja peninsula to better characterize the mineralization and deposit style of the Cacachilas district. Mineralization in the northeastern Sierra Cacachilas is mainly restricted to steeply dipping quartz veins, faults, and brittle-ductile shear zones that trend generally northeast. Some veins are en-echelon within the mineralized zones, implying some lateral movement along the zones. Veins are dominated by milky to clear quartz with trace sulfides, abundant limonite (after sulfides), and local open-space textures. Mineralization is interpreted to be intermediate between classic epithermal and mesothermal veins. Within mineralized trends and commonly associated with mineralization are greisen-like zones that are defined by intense sericitic to muscovitic overprint, trend northeast, and are with or without sulfides. The intensity of sulfide abundance and limonitic alteration after sulfides within and near mineralized zones is overall a good guide to mineralization. Based on past reports and on my recent studies, the Cacachilas district has very promising potential for relatively small, high-grade deposits.
Dissertation/Thesis
Masters Thesis Geological Sciences 2015

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40

Kallstrom, Michael Joseph M. S. in Geological Sciences. "Fluid and metal sourcing for the native silver deposits in the Batopilas Mining District, Chihuahua, Mexico." Thesis, 2012. http://hdl.handle.net/2152/ETD-UT-2012-08-6055.

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The Batopilas Mining District was a major silver producer, with estimated historic production of more than 300 million ounces. Orebodies consist of high-grade silver in the forms of native silver, acanthite and proustite hosted dominantly in calcite veins. Recent exploration has facilitated the reexamination of the geologic features and origin of the enigmatic native silver district. Sulfur, lead, and strontium isotopic studies have been conducted to constrain the fluid and metal sourcing. [delta]³⁴SvCDT isotope signatures for galena, sphalerite and pyrite range from -8 to -2, -6 to 0, and -5 to 3°/₀₀, respectively. A fractionation temperature of 227±25 °C can be obtained using average sulfur isotope values for galena and sphalerite. Galena lead isotopic values show two distinct signatures. Samples of massive-replacement style mineralization have ²⁰⁶Pb/²⁰⁴Pb, ²⁰⁷Pb/²⁰⁴Pb, and ²⁰⁸Pb/²⁰⁴Pb values of 18.742 and 18.747, 15.611 and 15.618, and 38.512 and 38.535, respectively. For vein samples, the corresponding values range from 18.799 to 18.817, 15.623 to 15.639, and 38.603 to 38.655. The lead isotopic signatures for vein galena have lower thorogenic lead content than other ore deposits in the Sierra Madre Occidental, suggesting a different source of metals. Vein calcite samples have ⁸⁷Sr/⁸⁶Sr isotopic compositions ranging from 0.707551 to 0.70590 (±0.000009) and Sr concentrations ranging from 51 to 246 ppm. These vein components may reflect mixed deep-marine sedimentary and Precambrian basement sources. A reconnaissance fluid inclusion study was conducted to better constrain fluid temperature and composition. The minerals studied included quartz, fluorite, and two types of sphalerite. The average eutectic temperatures obtained are -38°C, -31°C, and -43°C, respectively, indicating a complex mineralizing brine. Homogenization temperatures averaged 143°C, 165°C, and 174°C, and the NaCl equivalent weight percents averaged 4, 7, and 17, respectively. Fluids involved in vein mineralization are different from those typical of epithermal vein Ag-Au deposits, and may represent sedimentary brines that have circulated through the underlying basement.
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Anstett, T. F. "Grade-tonnage models of silver-copper-lead-zinc vein deposits of the Coeur d'Alene mining district, Idaho." 1986. http://catalog.hathitrust.org/api/volumes/oclc/14071286.html.

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Thesis (Ph. D.)--University of Wisconsin--Madison, 1986.
Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 145-148).

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張耿誌. "Thermo-Raman Spectroscopy of Amorphous Graphitic Carbon Deposites on Silver Surface." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/18887188187378540453.

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Abedinisohi, Parsoua. "Design and Fabrication of Silver Deposited TiO2 Nanotubes: Antibacterial Applications." Thesis, 2013. http://spectrum.library.concordia.ca/977431/1/Abedinisohi_MSc_F2013.pdf.

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Clean water is one of the most challenging issues facing humanity today resulting in widespread research on new water purification and disinfection techniques emphasizing on optimized energy consumption. Nanotechnology has significantly contributed to the lowering the cost of eco-friendly water disinfecting processes. Among many materials in this study TiO2 nanotubes with 90-100 nm pore diameter were synthesized using anodization method in an organic electrolyte containing fluoride ions. Deposition of Silver (Ag) on the large-surface TiO2 nanotubes showed significant antibacterial activity. To improve the uniformity of silver deposition a reductive doping was performed to increase the conductivity of the TiO2 nanotubes. Silver deposition was performed in a three-electrode electrodeposition cell using a cyanide-based silver electrolyte. Characterization of the films using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) confirmed the deposition of Ag onto the TiO2 porous layer. Liquid medium test under light illumination followed by serial dilutions resulted in perfect photo biocide efficiency of the immobilized Ag/TiO2 against E. Coli which is an emerging cause of food borne and waterborne illnesses.

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Chang, Wei-fu, and 張薇馥. "Preparation of Silver-Deposited Activated Carbon as Hybrid Materials for Disinfection." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/62155332496914575264.

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碩士
逢甲大學
環境工程與科學所
96
In the present study, the filtration/disinfection materials of silver-doped activated carbon were synthesized by direct impregnation of silver atoms or ions over carbon surface and was moderately modified using alkaline immersion techniques. In addition, the characteristics of material surface and its disinfection ability and mechanisms were evaluated thoroughly. According to our preliminary results, three kinds of silver-doped activated carbons prepared in this research, including nano silver, colloidal silver, and silver ion, were found to be effective on E. coli disinfection. However, it is also found that preparation by silver ion would not result in the clogging problem over porous materials whereas the other two silver depositions were observed to have severe shrinkage on adsorptive sites due to the coverage by inert additives or impurities. In addition, the surface area and pore volume of silver-doped activated carbon increases significantly by sodium hydroxide immersion, thus enhancing the concentration of deposited silver on activated carbon surface and accelerating the isoelectrical transformation of H-type from L-type, which could be beneficial on the chemical conjugation of silver ion on the carbon surface and reduction into silver atom. Ultrasonic wave was also employed to increase active sites with chemical adsorption. Moreover, the point of zero charge (pHPZC) of silver-doped activated carbon was experimentally estimated to be 8.79 which is higher the pH values as often seen in most natural water. This consequence would favor the attraction of negatively charged micro cells onto the surface of positively charged silver activated carbon to reveal better disinfection efficiency. The disinfection ability on E. coli and S. aureus in our batch experiment has demonstrated up to 98.0% within 30 minutes using as-prepared silver-doped activated carbon. In the disinfection test operated with continuous mode, the breakthrough volume of inflow solution containing E. coli was found to be approximately 700 liters by packing 15 gram of silver-doped activated carbon inside the filtration equipment. If the disinfection filtration is performed at larger flow velocity, such as 40 cm/min, the silver concentration released from the surface of activated carbon would be lower. After the breakthrough point was achieved, the used silver-doped activated carbon was then thermally reduced by purging hydrogen gas. Although the regenerated activated carbon can be satisfactorily used for E. coli disinfection again, the breakthrough volume would be decreased to 60 liters. Based on the experimental observance, the major disinfection mechanisms involved are silver-doped surface inactivation and the formation of reactive oxygen species.

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YU, ZHI-HENG, and 余至恆. "Optical Properties Investigation of Obliquely Deposited Silver Nanostructures on Different Substrates." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/2mn7s2.

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碩士
國立臺北科技大學
光電工程系
107
In this work, glancing angle deposition (GLAD) was performed in Direct Current (DC) magnetron sputtering to deposit silver(Ag) nanostructures on seeded substrates including square lattice type and triangle lattice type. Slanted Ag nanorod arrays were grown and their polarization dependent transmittance, reflectance and extinctance spectra were compared. By varying the spin rate with respect to the deposition rate, screw-like nanohelix arrays were grown. The circular dichroism was described with g-factor. It is found that an obvious helix array was fabricated at a substrate spin rate of 0.02rpm with respect to the deposition rate of 0.3nm/s and 0.4nm/s. The maximum g-factor is 0.6 for a sample fabricated at a substrate spin rate of 0.02rpm with respect to the deposition rate of 0.3nm/s. The influence of morphology parameters including pitch, wire width, radius of curvature and lattice constant on the circular-polarized transmittance and reflectance spectra is investigated with Finite-Difference Time-Domain (FDTD).

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Cheng, Xiaolin. "Mass changes during hydrothermal alteration, Silver Queen epithermal deposit, Owen Lake, central British Columbia." Thesis, 1995. http://hdl.handle.net/2429/7218.

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A procedure for determining metasomatic norms is developed in this thesis to quantitatively and objectively estimate mineral abundances from lithogeochemical data, The norm calculations use the same principles as do other norms such as CIPW, but the different mineral phases present in alteration systems are used as the normative standard minerals. Another distinctive difference between a metasomatic and a conventional norm is that the calculation procedure proposed for a metasomatic norm does not proceed along such a fixed hierarchical path as in the case of an igneous norm. A particular useful approach to the application of the norm concept to metasomatic rocks is to constrain the calculated normative mineralogy by a priori knowledge of existing minerals (i.e. to approximate the mode as closely as possible). Where an immobile component can be recognized the metasomatic norms for protoliths and altered rocks, as well as the chemical constituents lost or gained, can be further recast into the absolute amounts of minerals and chemical constituents relative to a given mass of parent rock. Known errors within lithogeochemical data studied can be propagated to the final results of all norm calculations. As a result, a chemico- mineralogical model for material exchange, including absolute losses and gains of chemical constituents, normative minerals in extensive units, as well as the corresponding propagated errors, is formulated in this work as follows: [equation diagram] Equation I is particularly useful because it is quantitative and easily applied: information that can be obtained from the equation includes the mineralogy of the initial and final rocks, absolute gains and losses of specific chemical constituents as well as the uncertainties on each estimate at a specified confidence level. The methodology for this approach is a natural extension of the use of Pearce element ratio (PER) diagrams for the study of metasomatic rocks. The metasomatic norm recovers the same quantitative information as do Pearce element ratio diagrams. The common principles are (i) correction for closure, that provides true relative lithogeochemical and mineralogical variations between parent and daughter rocks, and (ii) an effort to explain chemical variability in terms of mineralogical variability. The strategy of a PER diagram is to test whether chemical changes in different rocks can be explained purely by the variation(s) of certain mineral(s), as demonstrated by disposition of the binary plotted points along predefined trends (slopes). Metasomatic norms are displayed more effectively as equations or profiles showing the spatial distributions of normative mineral assemblage, as well as the absolute losses and gains of chemical constituents based on comprehensive mass balance relationships. The approach described in the first part of this thesis is applied to a hydrothermal alteration study of the Silver Queen mine in central British Columbia. Hydrothermal alteration at the Silver Queen mine was derived from a multiple precursor system. However, local, individual alteration profiles exhibit the attributes of a single precursor system. Six types of hydrothermal alteration at Silver Queen mine have been described: viz. propylitization, sericitization, argillization, silicification, pyritization and carbonatization. In general, the wall rock alteration in the study area is composed of a widespread regional propylitic alteration with superimposed carbonatization. Regional alteration gives way, as the vein is approached, to an outer envelope of sericitic and argillic alteration + carbonatization and an inner envelope of silicification and pyritization + sericitic or argillic alteration + carbonatization. Thus, the sequence of alteration development is (i) widespread regional propylitic alteration, (ii) sericitic and argillic outer envelope, and (iii) silicification and pyritization inner envelope. Most of the hydrothermally altered samples in alteration envelopes at the Silver Queen mine have gained mass during hydrothermal alteration. In contrast, samples from the profile of the northern segment of the No. 3 vein have lost mass. Other spatial variations of hydrothermal alteration from the southern segment to the northern segment of the No. 3 vein and from different levels (from 2600-foot level to 2880-foot level) have been recognized. In brief, the wall rock alteration is most intense in the alteration envelope at the central segment of the No. 3 vein and mildest at the northern segment of the No. 3 vein. The total mass change of each altered sample is largely the result of depletion of CaO and Na₂O, and addition of SiO₂, K₂O, H₂O and CO₂.

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Ching-ChuTseng and 曾景助. "P3HT/Titania Nanofiber Hybrid Photovoltaics with Penetrated Electrodes Deposited by Silver Nanopastes." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/63nw3u.

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Li, Jigang. "Electrical and optical properties of silver films deposited by high power impulse magnetron sputtering." 2008. http://proquest.umi.com/pqdweb?did=1574158131&sid=2&Fmt=2&clientId=14215&RQT=309&VName=PQD.

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Thesis (Ph.D.)--University of Nebraska-Lincoln, 2008.
Title from title screen (site viewed Jan. 15, 2009). PDF text: 136 p. : ill. (chiefly col.) ; 3 Mb. UMI publication number: AAT 3315317. Includes bibliographical references. Also available in microfilm and microfiche formats.

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Liou, Yiou-Hsin, and 柳耀翔. "Preparation and Characterisitics of Electrochemical Atomic Layer Deposited Copper-Silver Alloy Film on Interconnection." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/65m42k.

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碩士
國立虎尾科技大學
材料科學與綠色能源工程研究所
102
This paper describes the formation of Cu and Cu-Ag nanofilms using electrochemical atomic layer deposition (EC - ALD), which combine atomic layer deposition (ALD) with underpotential deposition (UPD). Ag materials and technigues may ultimately be need to address the low resistivity requirements of interconnection, which are project to have current density greater than 4.13 mA/cm2 by 2018, and super-filling Cu-Ag using the great gap filling of EC-ALD. The Si (100) wafer coated with 10 nm Ru films by pHysical vapor deposition, and the substrate was cleaned by cyclic voltammetry in 10 mM HCLO4 at a scan rate of 5 mV/s to remove the oxide layer. Cu underpotential deposition was used to deposit the first Cu atomic layer on Ru substrate. Pb was chosen as the sacrificial layer as it forms atomic layers on Cu via underpotential deposition and then Cu2+ solution was flushed into the cell at open-circuit potential where the Pb atoms were exchanged for Cu by redox replacements. The Cu bulk layer formation was by repeating the above step several times and then deposited Ag atomic layer on Cu using underpotantial deposition. Cu-Ag samples were formed using the sequence by performing 50 periods, each consisting of 4 cycles Cu and 1cycle Ag. The deposition were grown using 0.1 and -0.05 V for Cu and Ag precursor solution.The resulting Cu-Ag films were characterized using X-ray diffraction (XRD), electrochemical chromatograpHy and four point probe (FPP). The result indicates the average formed amount of Cu per replacement cycle was 0.51 ML, that the lowest resistivity 3.6 and 2.2 μΩ．cm for Cu thin film and Cu-Ag thin film. The XRD pattern for 500 cycles displays two left-shifted peak, (111) and (200) for Cu, its show that the Ag atom moved into Cu lattice. As results of the self-limiting reactions and electrochemical suface limited reaction, EC-ALD have the great ability-deposited of atomic-level control, fabricated nano-scale filling processes.

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Findley, Adam. "Structural, Mineralogical and Geochronological Constraints of the Miguel Auza Intermediate-Sulfidation Ag-rich Polymetallic Mineralization Deposit, Zacatecas, Mexico." Thesis, 2010. http://hdl.handle.net/1974/5536.

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The Miguel Auza mine, located in Zacatecas State, Mexico, is a vein-type polymetallic epithermal deposit hosted in deformed argillite, siltstone and greywacke of the Cretaceous Caracol Formation. Silver-rich base metal veins (0.2 m to >1.5 m wide) are spatially associated with NE-striking, steeply SE- dipping (70-80º) faults over a strike length of 1.6 km and a depth of 460 m. Three distinct structural stages are correlated with hydrothermal mineral deposition: Stage I is characterized by normal faulting and early hypogene alteration of the sedimentary rock. Stage II is associated with reverse-sense reactivation of early normal faults, dilation of bedding planes/fractures, and deposition of barren calcite + pyrite veinlets. Sub-stages IIA and IIB are related to the development of reverse-fault-hosted quartz-carbonate sulphide veins and characterize the main stage of mineralization. Associated hydrothermal minerals during the main stage of mineral deposition are quartz, muscovite, and calcite. Stage III involves late NW-SE striking block faulting, brecciation and calcite veining. Later supergene oxidation of veins led to deposition of Fe-oxides and hydroxides. The main Ag-bearing minerals comprise pyrargyrite, tetrahedrite- freibergite, polybasite-antimonpearceite, and acanthite, with associated sulphides including galena, sphalerite, chalcopyrite, arsenopyrite and pyrite. In the main ore zone, base metal sulphides are commonly intergrown with the Ag-bearing sulfosalts. Compositions of Ag-rich tetrahedrite + pyrargyrite + sphalerite indicate a primary depositional temperature around 325-350ºC for the late phase of sub-stage IIB. 40Ar/39Ar dating of wall-rock illite associated with stage I alteration yields an age of 46.58 ± 0.30 Ma. Ages of 46.01 ± 0.55 Ma, and 44.55 ± 0.22 Ma were obtained for vein muscovite related to the main stage (sub-stage IIB) of ore deposition. These ages correspond to the later stage of the Laramide orogeny in Northern Mexico. The geometric relationship between the various structures, vein types, and the regional Miguel Auza fault zone suggest episodic reverse-sense reactivation of normal faults. Based on (1) the tectonic setting, (2) spatially related igneous rocks, (3) ore and gangue mineralogy, and textures (4) geochemical signature, and (5) inferred temperature of formation, the Miguel Auza deposit is interpreted to be an intermediate-sulfidation type deposit.
Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2010-04-15 13:04:06.104

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