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1

Wheadon, C. J. D. (Christopher James Daniel), and n/a. "A systemic approach to understanding prehistoric shell-bearing deposits in New Zealand: a case study from Shag Point, North Otago." University of Otago. Department of Anthropology, 2002. http://adt.otago.ac.nz./public/adt-NZDU20070507.115526.

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This thesis describes a systemic approach to the study of shell remains, using material from the site of Shag Point (J43/11), in North Otago. This approach analyses the relationship between sampling, identification, quantification, and site formation processes. An historical and methodological framework is used to assess the analysis of shell-bearing deposits in New Zealand, and provide innovative solutions to bias. Historical research outlines the common research methods in New Zealand, which are relevant to Shag Point. Methodological research outlines the range of potential research methods used in the study of shell-bearing deposits. Reviewing the data from Shag Point, sampling, identification, quantification, and site formation processes are used to assess the quality of data from the site. Data from coastal sites are commonly used to generate regional level syntheses. These syntheses do not deal with all of the possible sources of bias in shell-bearing deposits. Cumulative sampling is used to assess representativeness. The data from Shag Point are indicative of a representative sample. The site is compared to three other coastal southern South Island assemblages: the nearby Shag River Mouth, Pleasant River, and Pounawea. The data from Shag River Mouth may be representative; the same cannot be said for the Pleasant River and Pounawea archaeological assemblages, thus hampering regional-level syntheses.
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2

Chandupatla, Udaya B. "Evaluation of power deposited in a homogenous head model for clam-shell type cellular phones." FIU Digital Commons, 2006. http://digitalcommons.fiu.edu/etd/2106.

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The fundamental dosimetric quantity used to measure the level of exposure due to cellular phones is the Specific Absorption Rate (SAR). The compliance of a device to the exposure limit is determined by following the guidelines described in IEEE measurement standards. The compliance assessment process can be quite complicated and time consuming, due to the many different test conditions that have to be considered and the slow speed of the measurement equipment. Depending on the frequency, use configuration of the device and form factor the SAR values can vary significantly from test case to test case even for the same device. This work shows that for a particular form factor, indicated as clam shell, where the phone is made of two halves that rotating around a hinge, one of the required test condition, described as tilt position, always provides lower SAR values than touch position, the other test condition. Different frequencies, antenna locations and antenna types have been considered. The results obtained with the well-known Finite Difference Time-Domain (FDTD) method have been validated with measurements. A robotic assessment tool (DASY4) is used for measurement purpose.
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3

De, Decker RH. "The geological setting of diamondiferous deposits on the inner shelf between the Orange River and Wreck Point, Namaqualand." Master's thesis, University of Cape Town, 1986. http://hdl.handle.net/11427/26236.

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4

Moriarty, Julia M. "Transport and Fate of Sediment on the Waipaoa River Continental Shelf: Implications for the Formation and Reworking of Flood Deposits." W&M ScholarWorks, 2012. https://scholarworks.wm.edu/etd/1539617920.

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As part of a large interdisciplinary study, particulate fluxes in the Waipaoa River sedimentary system in New Zealand have been studied from the terrestrial headlands of the catchment to the oceanic basin over timescales spanning storm events, seasons, and the Holocene. Here, we complement prior efforts by evaluating the formation and reworking of riverine deposits during episodic flood and wave events, and considering their role in accumulation patterns created over longer timescales on the Waipaoa shelf. Using a numerical hydrodynamic and sediment transport model, sediment fluxes and deposition were analyzed from January 2010 through February 2011. A version of the three dimensional ROMS-CSTMS (Regional Ocean Modeling System – Community Sediment Transport Modeling System) was used to investigate the spatial and temporal variability of sediment fluxes on the Waipaoa shelf. The model could account for river input, waves, winds, larger-scale currents, tides, multiple sediment classes and a multi-layered seabed. Sediment sources to the water column included both the river plume and resuspension from the seabed. For model stability and to prevent the reflection of the river plume at the open boundary, the Waipaoa shelf model was nested within a larger-scale New Zealand ocean model. Model inputs were based on observations and model estimates, depending on availability.
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5

Rau, Grant. "A geological evaluation of marine diamond placer deposits on the central Namibian inner shelf : a case study of the Hottentot Bay area." Thesis, Rhodes University, 2004. http://hdl.handle.net/10962/d1007554.

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This study focusses on the marine diamond placers within Exclusive Prospecting Licence 1950 and Mining Licence 103a, located northwest of the north-facing Hottentot Bay which is 60 km north of Lüderitz, along the central Namibian coastline. The thesis follows the natural geological evolution of the marine placer deposit from primary source, through alluvial and/or glacial transportation, concentration along the coastline by wave, aeolian and alluvial/sheet-wash processes and finally marine diamond placer preservation. All of these processes are reviewed as they are important in understanding of the evolution marine placer deposits. The poly-cyclic role of coastal aeolian, alluvial, and marine processes, in marine placer enrichment is shown to be particularly important in considered target identification and prioritisation. A detailed bathymetric, sonographic and seismic interpretation, is an integral part of diamond placer exploration, and was used to examine and describe surficial and sub-bottom characteristics within the study area. Marine placers are formed along palaeo-strandlines during periods of marine transgression and regression and are therefore fundamental in marine placer exploration. A detailed bathymetry map, compiled for this study, of the area between Lüderitz Bay and Clara Hill, provides the foundation for a detailed terrace level investigation. Regionally, twelve well-developed stillstand levels are identified, nine of which fall into the study area. These interpretations are compared with global eustatic as well as terrace and resource/reserve levels in the Lüderitz area and are found to correlate well. Sediment dynamic studies involve the use of accredited application software for wave refraction modelling, to determine the wave angle and orbital wave velocity at the seabed. Bedload velocities, required to move diamonds of specific sizes, can be empirically determined and therefore areas of diamond entrainment and deposition can be modelled and target features delineated and prioritised. These detailed interpretations provide a sound platform for evaluating diamond placer process models in the study area. By integrating both previously published and newly formulated ideas, a revised, holistic model for the formation of marine diamond placer deposits in central Namibian is postulated. The proposed model is tested by comparing it to the lateral distribution of presently defined resource/reserve areas in the Lüderitz area and shows a close correlation with most of these enriched deposits. Based on this model, a matrix for the delineation and prioritisation of marine placer deposits is developed and the best target features within the study area are identified.
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6

Lodewyks, Therisia. "Siesmic Stratigraphy of Upper Pleistocene gravel and holocene mudbelt deposits between wreck point and the kamma river on the western shelf of South Africa." Master's thesis, University of Cape Town, 2010. http://hdl.handle.net/11427/4208.

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This project aims to provide a better understanding of the deposition of Quaternary and Holocene sediments along the west coast of Southern Africa between Wreck Point at approximately 28º50.00′S and the Kamma River at approximately 29º20.00′S, based primarily on seismic stratigraphy. The high resolution airgun seismic survey performed by De Beers Marine during 1998 was interpreted based on seismic stratigraphic principles and the chronology of the seismic profiles was based on correlation to radiocarbon-dated gravity cores from offshore the Holgat River determined by Herbert (2009). Seismic profiles were interpreted to the north and south of the central Holgat River sequence with the identified Type 1 Sequence divided into systems tracts. The Type 1 Sequence Boundary represents a major erosional unconformity formed as a result of tectonic uplift and a relative drop in sea level. A wave-cut knick point provides accommodation space for the deposition of Pleistocene and Holocene sediment above the erosional unconformity. The Lowstand Systems Tract (LST) consists of a condensed gravel lag. The LST is divided into subunits where possible which reflect the complex depositional history as the gravel lag was variably reworked as the strandline migrated across the shelf in response to late Pleistocene sea-level fluctuations. This study attempts to delineate some of the more distinctly different units within the economically important gravel body of the LST. The extent and seismic character of five subunits were identified within the complex LST. The Transgressive Systems Tract (TST) formed after a rapid rise in sea level between 19 and 7 thousand years ago (ka). Two transgressive packages were formed as sea level migrated landward. An older deeper water package was identified and labelled Unit 4 while a younger shallower water package was identified upslope, Unit 5, as the mudbelt depocentre migrated landward. The Highstand Systems Tract (HST) is characterized by a set of prograding sigmoidal clinoforms having formed in response to increasingly limited accommodation space after 5.5 ka. Clinoforms, seismic reflectors with slightly higher amplitude than the underlying units, represent depositional hiatuses during periods of lower sedimentation rates. The HST units show southward progradation as accommodation space around the Orange River Mouth became limited. The resulting sequence startigraphy and stratal geometries of the studied sequence are controlled by sea level fluctuation, accommodation space and sediment supply.
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7

Bohrer, Arndt. "Entwicklung eines internetgestützten Expertensystems zur Prüfung des Anwendungsbereichs urheberrechtlicher Abkommen." Kassel : Kassel Univ. Press, 2003. http://deposit.d-nb.de/cgi-bin/dokserv?idn=97032314X.

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8

Delaine, Maxence. "La composition des thèques d'amibes xénosomiques : utilisation potentielle comme bio-indicateur des dépôts de particules d’origine atmosphérique." Thesis, Besançon, 2016. http://www.theses.fr/2016BESA2017/document.

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Les amibes à thèque, également appelés thécamoebiens, sont des micro-organismes unicellulaires, qui construisent une enveloppe rigide, appelée thèque (Adl et al., 2012). Ces thèques ont des tailles, formes et natures très variées (Ogden & Hedley, 1980). Les récentes études sur la composition des thèques ont conduit à émettre l’hypothèse que les amibes xénosomiques (constituées de particules exogènes), peuvent constituer des bio-indicateurs pertinents de la diversité particulaire de l’environnement minéral, organique et biologique dans lequel elles évoluent.L’objectif principal des recherches menées au cours de cette thèse vise donc à caractériser la composition des thèques d’amibes xénosomiques et à en évaluer leur utilisation potentielle en tant que bio-indicateurs des dépôts de particules d'origine atmosphérique. Pour cela, des thèques d’amibes ont été analysées in situ en conditions naturelles et après dépôts artificiels de particules minérales allochtones.Ces travaux permettent de dégager plusieurs conclusions majeures :(1) La taille des particules minérales intégrées dans la thèque xénosomique de Bullinularia indica est similaire à celle des particules minérales transportées dans l'atmosphère; (2) les particules minérales intégrées dans les thèques sont des silicates stables dans les conditions physico-chimiques régnant dans les tourbières, les bryophytes et les sols étudiés; (3) certains minéraux comme la phlogopite, même lorsqu’ils sont présents en de fortes concentrations, ne sont jamais intégrés par les amibes; (4) la combinaison des observations portant sur la taille, la forme et la nature des particules utilisées par des amibes xénosomiques permet de poser les bases de l'utilisation des amibes à thèques pour la bio-indication de la diversité particulaire atmosphérique récente ou ancienne
Theca-like amoebae, also called thecaamoebius, are unicellular microorganisms, which construct a rigid envelope called theca (Adl et al., 2012). These themes have very varied sizes, shapes and natures (Ogden & Hedley, 1980). Recent studies on the composition of the themes have led to the hypothesis that xenosomal amoebae (constituted by exogenous particles) can constitute relevant bio-indicators of the particulate diversity of the mineral, organic and biological environment in which they evolve . The main objective of the research carried out during this thesis is therefore to characterize the composition of the xenosomal amoebae and to evaluate their potential use as bioindicators of deposits of atmospheric particles. For this purpose, amoeba theae were analyzed in situ under natural conditions and after artificial deposits of allochtonous mineral particles. Several major conclusions can be drawn from this work: (1) The size of the mineral particles integrated in the xenosomal theca of Bullinularia indica Is similar to that of mineral particles transported into the atmosphere; (2) the mineral particles integrated into the thecs are stable silicates under the physico-chemical conditions prevailing in the peatlands, bryophytes and soils studied; (3) some minerals such as phlogopite, even when present in high concentrations, are never integrated by amoebae; (4) the combination of observations on the size, shape and nature of the particles used by xenosomic amoebae forms the basis for the use of tea amoeba for bioindication of recent or former atmospheric particulate diversity
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9

Suarez, Suzette V. "The outer limits of the continental shelf : legal aspects of their establishment /." Berlin [u.a.] : Springer, 2008. http://deposit.d-nb.de/cgi-bin/dokserv?id=3103207&prov=M&dok_var=1&dok_ext=htm.

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10

Мельничук, П. М. "Особливості геологічної будови і перспективи нафтогазоносності нижньокрейдових відкладів північно-західного шельфу Чорного моря." Thesis, Івано-Франківський національний технічний університет нафти і газу, 2005. http://elar.nung.edu.ua/handle/123456789/4064.

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Роботу присвячено вияшіенню особливостей геологічної будови нижньокрейдових відкладів північно-західного шельфу Чорного моря і визначенню перспектив їх нафтогазоносності та пріоритетних напрямків подальших пошуково-розвідувальних робіт. Побудовано структурно-тектонічні карти покрівлі та підошви нижньокрейдових відкладів. Виділено типи літофацій та побудовані карти їх просторового поширення і розвитку порід-колекторів. Проведено районування території поширення нижньокрейдових відкладів за ступенем їх перспективності на підставі критерійних ознак нафтогазоносності та щільності початкових прогнозних ресурсів вуглеводнів, за результатами яких побудовано карти перспектив нафтогазоносності готерів-верхньоаптських і верхньоальбських відкладів. Обґрунтовано на підставі рейтингової оцінки пріоритетні напрямки геологорозвідувальних робіт на нафту і газ та першочергові об’єкти для проведення параметричного і пошукового буріння та пошукових і детальних сейсморозвідувальних робіт.
Работа посвящена изучению особенностей геологического строения нижнемеловых отложений северо-западного шельфа Черного моря, определению перспектив их нефтегазоносности и приоритетных направлений дальнейших поисково-разведочных работ на нефть и газ. На основании современных геолого-геофизических материалов и данных глубокого бурения построены структурно-тектонические карты по кровле и подошве для отложений этого возраста. Выделены типы литофаций и построены карты их пространственного развития. Рассмотрены критерии перспектив нефтегазоносности нижнемеловых отложений. Проведено районирование территории распространения нижнемеловых отложений за степенью их перспективности на основании критериев нефтегазоносности и плотаости начальных прогнозных ресурсов углеводородов, по результатам которых построены карты перспектав нефтегазоносности нижнемеловых отложений. Обосновано на основании рейтинговой оценки приоритетные направления геологоразведочных работ на нефть и газ и первоочередные объекты для проведения параметрического и поискового бурения и поисковых и детальных сейсморазведочных работ. Выявлено, что наиболее нефтегазоперспективные зоны приурочены к Каркинитскому и Каламитскому газоносным районам, общие ресурсы углеводородов которых соответственно для нижнемеловых отложений составляют 283,6 и 120,9 млн.т. у.т. Менее перспективными являются территории Нижнепрутско-Килийского (57,2 млн.т. у.т.), Алуатско-Тузловского (39,4 млн.т. у.т.) нефтегазоносных районов и Таврийского (3,9 млн.т. у.т.) перспективного района. Бурение параметрических и поисковых скважин в первую очередь рекомендуется проводить на площадях: Угловая, Рифтовая, Осетровая, Штормовая, Янтарная, Олимпийская, Краевая, Комсомольская, Зональная, Губкина, Корнилова, Нахимова, Каламитская и Гордиевича.
The thesis is devoted to the exposure of geological structure features of low cretaceous deposits of the Black sea north-western shelf and determination of perspectives of their oil and gas bearing and priority directions of subsequent searching-reconnaissance works. The structural-tectonic cards of roof and sole of low cretaceous deposits are built. The types of litofasciae are selected and cards of their spatial distribution and development of breeds-collectors are built. Districting of territory distribution of low cretaceous deposits is conducted after the degree of their perspectives on the basis of criterion signs of oil and gas bearing and closeness of initial prognosis resources of hydrocarbons as a result of which the cards of prospects of oil and gas bearing are built basal and upper albian deposits. On the basis of rating estimation priority directions of geological survey works on an oil and gas and primary objects for conducting of the parametric and searching drilling and detailed seismic reconnaissance works are defined.
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Machado, Cruz Alberto. "Integrated geological and geophysical studies applied to understanding the evolution of the Offshore Amazon Basin." Electronic Thesis or Diss., Sorbonne université, 2018. http://www.theses.fr/2018SORUS466.

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Le Bassin de l'Embouchure de l'Amazone (en portugais Bacia da Foz do Amazonas) est situé dans l'extrême nord de la Marge Équatoriale Brésilienne. Ce bassin a attiré l'attention de la communauté scientifique pendant plusieurs décennies en raison de ses processus sédimentaires à grande échelle liés à l'afflux colossal de sédiments fourni par l’Amazone. Cependant, la plupart des investigations menées sur ce bassin étaient limités à sur la partie supérieure de la succession Quaternaire de le Cône d'Amazone et certains travaux pionniers visant des strates plus profondes ne disposaient pas d'un contrôle chronostratigraphique fiable. Afin de mieux comprendre l'évolution temporelle et spatiale de la succession stratigraphique post-rift du Bassin de l'Embouchure de l'Amazone, des études multidisciplinaires soutenues par des interprétations de données sismiques, diagraphiques, chronostratigraphiques et de modèles de anomalies gravitaires et magnétiques ont été réalisées au cours de cette thèse
The Offshore Amazon Basin (known in Portuguese as Bacia da Foz do Amazon) is located in the far north of the Brazilian Equatorial Margin. This basin has attracted the attention of the scientific community for several decades due to its large-scale sedimentary processes related to the colossal sediment influx provided by the Amazon River. However, most of the investigations carried on the Offshore Amazon Basin were restricted to the uppermost Quaternary succession of the Amazon Deep-sea Fan and some pioneer works aiming deeper strata lacked a reliable chronostratigraphic control. In order to better understand the temporal and spatial evolution of the post-rift stratigraphic succession of the Offshore Amazon Basin, multidisciplinary studies supported by interpretations of seismic, well log, chronostratigraphic data and geophysical potential field models were carried out during this PhD thesis
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Kenady, Selene L. "Geophysical explorations of archaeological shell matrix sites: evaluating geophysical techniques in determining the boundaries, structure and volume of buried shell deposits." Thesis, 2016. https://researchonline.jcu.edu.au/50093/1/50093-kenady-2016-thesis.pdf.

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Shell middens are a significant component of the Australian coastal archaeological record, however, they are notoriously difficult to research. Shell matrix sites are often large and structurally heterogeneous with complex formation histories. For large stratified shell matrix sites, the majority of the deposits are buried making the design of appropriate and representative sampling regimes challenging, as short of total excavation the population from which the sample was taken will never be fully understood. This study aims to address these sampling issues through the application of geophysical survey techniques to shell matrix sites, and by developing novel methods for creating three-dimensional models and volume estimates of buried shell deposits from these survey results. An extensive literature review found only 22 published papers (representing 15 archaeological case studies) have applied geophysical surveys to shell matrix sites. Not one of these studies used geophysical methods to calculate volume estimates of the buried matrices or to create three-dimensional models of the deposits. Outside of archaeology, there have been studies (typically in glacial load research) which have attempted to create volume estimations from geophysical survey results. These studies have, however, typically not included ground truthing of results or calculated error values for the volume estimates. This research has three primary aims: (1) to delineate and map buried shell matrix deposits in tropical Australian contexts; (2) to establish methods for transforming these survey results into volume estimates and three-dimensional models of the deposits; and (3) is to test the accuracy of these models and estimates. To achieve these aims two geophysical methods were chosen and compared; ground-penetrating radar (GPR) and electrical resistivity. These two geophysical methods were chosen, on the basis of the literature review, as being the most appropriate methods to meet the research aims. Both survey methods were employed under field and experimental conditions. Survey results were processed and then exported to Esri's ArcGIS suite of software for further processing, to create the three-dimensional models and volume estimates. Results from this modelling were then compared to the in-ground deposits to test their accuracy. Survey and modelling results for the buried shell matrix deposits varied between geophysical method, and were dependent on the environmental conditions present on site. The electrical resistivity could not differentiate shell material from sand, but could differentiate shell from an organic-rich sediment. The GPR produced clearer, easier to interpret results under drier conditions, while the electrical resistivity produced them under wetter conditions. The modelled results showed more accurate three-dimensional representations of buried shell matrices could be created from the GPR, rather than the electrical resistivity surveys. Similarly, the volume calculations were highly accurate when based on GPR survey data, with an error margin on the estimates of 16%±11%, though it was found that small misinterpretations of the results can easily produce errors in excess of 50%. Volume calculations based on the electrical resistivity data were less accurate than the GPR and varied significantly depending on how the results were interpreted, meaning their overall error margin was significantly higher at 50%±29%. The geophysical survey results for this research also provided a greater understanding of the palaeolandscape on which the shell matrix at the field site was deposited. In order to create accurate accounts of the archaeological record of coastal Australia it is vital that improved methods for characterising the variability of shell matrix sites are explored. The current research addressed this issue by evaluating the capabilities of two geophysical survey techniques in investigating buried shell matrices, and by developing methods for transforming the survey results into three-dimensional models and volume estimates. These methods provide a way to greatly improve sampling regimes in shell matrix research by providing an understanding of the buried deposits before excavation takes place. The methods also provide information in their own right, allowing for a better understanding of the size and shape of buried matrices, and the palaeolandscapes on which they were deposited.
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Nelson, Storr L. "Lower and Middle Devonian carbonate-platform and outer-shelf-basin deposits flanking Railroad Valley, Nevada." Thesis, 1996. http://hdl.handle.net/1957/34319.

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Lower and Middle Devonian strata crop out on the former stable carbonate platform that existed in the Quinn Canyon Range, through the carbonate shelf edge in the Pancake Range, to the carbonate slope and outer-shelf basin in the Reveille Range. The strata of the Reveille Range record a transition from deposition on the carbonate platform in the Lower Devonian, to deposition at the carbonate platform margin, to deposition in the outer-shelf basin in the Middle Devonian. Conodonts collected from the base of the Sevy Dolomite yield a kindlei-Zone age, an indication that the Sevy Dolomite is younger than previously recognized. Throughout the Lower and Middle Devonian, carbonate strata of the Pancake Range and Quinn Canyon Range were deposited on the shallow carbonate platform. Conodonts collected from the base of the Lower Alternating Member of the Simonson Dolomite in the Quinn Canyon Range have a slightly older age (serotinus- to costatus Zone) than other eastern Nevada locations. The Lower Devonian Sevy Dolomite was deposited in a shallow carbonate subtidal through supratidal environment and is similar in outcrop throughout the ranges. Petrographic studies show that the samples are lithologically and diagenetically similar, indicating a similar intensity of dolomitization from the precursor calcareous mudstone. The Formation classifies as bioturbated mudstone and wackestone. The Middle Devonian Simonson Dolomite was deposited in shallow carbonate subtidal through supratidal environments. The Simonson Dolomite was affected by Milankovitch Cycles, glacioeustatic oscillations of sea level, producing a characteristic rhythmic bedding. The Middle Devonian Sadler Ranch Formation and Denay Limestone are lithologically and diagenetically different from the shallow water deposits of the Lone Mountain Dolomite, Sevy Dolomite, and Simonson Dolomite. The Sadler Ranch Formation and Denay Limestone were deposited at the carbonate platform edge and on the carbonate slope and outer-shelf basin, respectively. The Sadler Ranch Formation is dolomitized and may be classified as fossiliferous wackestone and mudstone. The Denay Limestone is not dolomitized and is classified as mudstone and fossiliferous grainstone and packstone. Dolomitization in the Paleozoic strata of Nevada is a secondary feature, an early diagenetic replacement of strata which were originally limestone. This replacement process was controlled by transgressions and regressions of the shoreline. Shallow carbonate platform deposits (shelfal and tidal-flat) are dolomitized, whereas deep water outer-shelf basin and slope deposits are not.
Graduation date: 1997
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14

Velozzi, David Micheal. "Sedimentary features of the Yangtze derived mud deposits on the inner shelf of the East China Sea." 2005. http://www.lib.ncsu.edu/theses/available/etd-04132005-164824/unrestricted/etd.pdf.

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15

Weber, S. "Insights into the formation of the Stuart Shelf iron-oxide-copper-gold (uranium) system from magnetotellurics." Thesis, 2010. http://hdl.handle.net/2440/106281.

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The Gawler Craton, South Australia, is host to many economic ore resources. Of which, iron oxide copper-gold deposits, such as Olympic Dam, Carrapateena and Wirrda Well, stand out due to the quality and abundance of their ore resources. Understanding the mechanisms of their formation is vital for defining exploration models for future development. 166 stations of magnetotelluric data at periods between101-104 seconds have been used to produce three, 2D models that provide insight into the electrical conductivity of the sub-surface beneath the Stuart Shelf. Links between corresponding regions of conductivity across profiles are shown by faults. It is suggested here that the faults are the fluid flow pathways for the mineralizing hydrothermal fluids. These fluids have been derived from the mantle and the surface in two phases of fluid flow causing both deposition and destruction of graphite respectively.
Thesis (B.Sc.(Hons)) -- University of Adelaide, School of Physical Sciences, 2010
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16

Wen, Sheng-Wen, and 溫盛文. "Structural characterization of ZnO/ZnS core-shell nanostructures deposited at atmospheric pressure using DEZn, N2O and DTBS." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/54299067500361361583.

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碩士
國立中興大學
物理學系所
104
In this thesis, ZnO nanowires and radial ZnO/ZnS core-shell nanostructure arrays were deposited at atmospheric pressure in a temperature range of 300 ~ 600 oC with diethylzinc (DEZn), nitrous oxide (N2O) and ditert-butylsulfide (DTBS) precursors serving as sources of Zn, O and S elements in the ZnO nanowires and radial ZnO/ZnS core-shell nanostructures. The physical properties of radial ZnO/ZnS core-shell nanostructures were characterized using θ-2θX-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), and photoluminescence spectroscopy (PL). It was found that both ZnO and ZnS were wurtzite structure in nature based upon HRTEM investigations. Moire fringes were identified in the radial ZnO/ZnS core-shell nanostructure with a good agreement in the lattice mismatch between ZnO and ZnS in the pseudomorphic ZnO/ZnS core-shell nanostructure. Finally, a slight red-shift in the near band edge (NBE) emissions of the RT PL of the ZnO/ZnS core-shell nanostructures was observed.
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17

Huang, Chun-Chih, and 黃俊智. "Enhancing the Methanol oxidation Activity of Direct Methanol Fuel Cell with Core-Shell Ni-Pt Nanocatalysts Deposited on CNT Electrode." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/g8s9p6.

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18

Wang, Jang-Jung, and 王建中. "Enhancing the Methanol Electrooxidation Activity of Direct Methanol Fuel Cell with Core-Shell Ru-Pt Nanocatalysts Deposited on CNT Electrode." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/71513337705771810462.

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19

Koch, Jennifer Lynn Donoghue Joseph F. "Late Quaternary evolution of the northwest Florida coast and margin development of a conceptual model for identifying and characterizing shelf sediment deposits /." 2006. http://etd.lib.fsu.edu/theses/available/etd-04092006-143206.

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Thesis (Ph. D.)--Florida State University, 2006.
Advisor: Joseph Donoghue, Florida State University, College of Arts and Sciences, Dept. of Geological Sciences. Title and description from dissertation home page (viewed Dec. 4, 2006). Document formatted into pages; contains xxi, 292 pages. Includes bibliographical references.
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20

Rocha, Pedro Ferrara Pires da. "Characterization of the sedimentary deposit of the Costa da Caparica inner shelf as a tool to support coastal management." Master's thesis, 2020. http://hdl.handle.net/10400.1/15404.

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Currently 60% of the global population is concentrated in the coastal zone and 75% of the coast is dominated by sandy beaches, thus, the susceptibility of these environments to anthropogenic impact as coastal erosion increases is unquestionable. One common and effective measure for minimizing beach erosion, which has global appeal, is artificial sand nourishment. However, locating a good sediment borrow area especially inland, has become very difficult. Offshore sediments are identified as a good solution. Hence, this study had the objective to do the characterization and definition of sedimentary units of 12 cores (3 meters long each) located between the water depths of 21 m to 27 m of the offshore borrow area of Costa da Caparica, aiming to be used for beach nourishment. Mean grain-size, carbonate content, kurtosis, sorting, skewness and the textural composition are used to characterize and define the sedimentary units of each core. The 3 meters length cores were analyzed with a resolution of 25 cm. A multivariate statistical (PERMANOVA, MDS, Cluster, SIMPER and PCA) approach was used to support the definition of the sedimentary units. The results showed four different sedimentary units. The Unit 1 characterized by medium and fine sand, the Unit 2 by coarse sand, the Unit 3 by fine sand and the Unit 4 by fine and medium sand. Unit 2 is the most observed unit, followed by the units 1, 3 and 4. The PERMANOVA showed significant difference (p < 0,05) between the sedimentary units corroborating with the units definition. The PCA showed correlation to medium and coarse sand with the Units 1, 2 and 4 and to fine sand with the Unit 3. The borrow area shows 3 compatible sedimentary Units, the Unit 1, 2 and 4 which can be used in future nourishment projects in Costa da Caparica.
Atualmente 60% da população global está concentrada nas zonas costeiras e as praias arenosas representam 75% do ecossistema costeiro. Face à crescente ocupação urbana na zona costeira os impactos antrópicos nessas áreas como a atuação da erosão é inquestionável. Uma das abordagens globalmente utilizada para mitigar os impactos da erosão costeira é a alimentação artificial de praias. Entretanto as manchas de empréstimo continentais estão cada vez mais escassas e o sedimento da plataforma continental é pontuado como uma solução. O presente estudo teve como objetivo caracterizar e definir as unidades sedimentares da mancha de empréstimo da Costa da Caparica, localizada na plataforma continental interna de Portugal, com o intuito da utilização futura desse sedimento em projetos de alimentação artificial de praia. A concentração de carbonatos, média granulométrica, curtose, assimetria, calibragem do sedimento e percentagens das diferentes classes texturais foram utilizadas para caracterizar e definir as unidades sedimentares de cada testemunho. Os 12 testemunhos de 3 metros de comprimento cada, foram analisados com resolução de 25 cm. Para apoiar a definição das unidades sedimentares foi utilizada uma abordagem estatística multivariada (PERMANOVA, MDS, Cluster, SIMPER e PCA). Os resultados mostraram quatro unidades sedimentares. A Unidade 1, caracterizada por areia média e fina, a Unidade 2 por areia grossa, a Unidade 3 por areia fina e a Unidade 4 por areia fina e média. A unidade 2 é a mais observada, seguida pelas unidades 1, 3 e 4. A PERMANOVA mostrou diferença significativa (p <0,05) entre as unidades sedimentares. A PCA apresentou correlação de areia média e grossa com as Unidades 1, 2 e 4 e de areia fina com a Unidade 3. A área de empréstimo apresenta 3 Unidades sedimentares compatíveis, as Unidades 1, 2 e 4 que podem ser utilizadas para futuros projetos de alimentação de praia na Costa da Caparica.
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21

Kümmerer, Vincent. "Anomalous levels in the southern Portuguese continental shelf sedimentary record: potential evidence of the 1755 CE Lisbon Tsunami." Master's thesis, 2019. http://hdl.handle.net/10400.1/15015.

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At present, knowledge about tsunami event deposits in outer shelf environments with water depths > 60 m is limited, although understanding of the involved processes as tsunami induced erosion of seafloor sediments and induced backwash currents are critical for tsunami hazard assessment. Both, incoming tsunami waves and generated backwash currents can leave signatures in the offshore sedimentary record. Preservation of tsunami imprints seems more likely in offshore deposits as in onshore deposits, which are in contrary more regarded. Thus, a multidisciplinary approach was conducted to detect probable imprints left by the 1755 Lisbon tsunami event in 3 cores from the southern Portuguese continental shelf with water depths > 57 m. Age model results, based on 14C and 210Pb ages, confirm the ages of the sediment to the 1755 Lisbon tsunami event. Other extreme events such as storms can be excluded trough hydrodynamic considerations. Implementing new high-resolution methodologies as the multivariate analyses of sand composition and microtextural features on quartz grain surfaces yielded more evidence for a tsunamigenic origin of previous detected high energy event layers in the studied core sections in the context of ASTARTE project, although no remarkable terrigenous signal is present. The heterogenous and mixing character of the probable 1755 Lisbon offshore tsunami deposits coupled with hydrodynamic considerations suggest, that subunits related to different tsunami wave incursions and backwash phases re unlikely to be preserved in similar environments as the study area. Also, spatial depositional differences of tsunami sediments were encountered in the study area by differences in mean grain size, sand composition, and simulated horizontal surface velocities. The new applied methodologies contribute paleo-tsunami layer identification and facilitate new studies on offshore tsunami deposits. While the southern Portuguese shelf seems to be a very good study area, we suggest for near future works to collect multiple cores aligned in transects for a better understanding of tsunami sedimentation dynamics
Atualmente, o conhecimento sobre os depósitos de eventos de tsunamis em ambientes de plataforma externa com profundidades de água > 60 m é limitado, embora a compreensão dos processos envolvidos, como a erosão induzida pelo tsunami de sedimentos do fundo do mar e correntes de retorno, seja fundamental para a avaliação do risco de tsunamis. Tanto as ondas de tsunami que chegam quanto as correntes de retorno geradas podem deixar assinaturas no registo sedimentar offshore. A preservação das marcas do tsunami parece mais provável nos depósitos offshore do que nos depósitos onshore, embora sejam estes últimos os mais estudados. Neste contexto, foi realizada uma abordagem multidisciplinar no registo sedimentar potencialmente relacionado com o tsunami de 1755 que afectou Lisboa, com base em 3 sondagens da plataforma continental do sul de Portugal, a profundidades maiores que 57 m. Os resultados do modelo de idades que conjuga dados de 14C e 210Pb, confirmam a relação deste registo com o tsunami de Lisboa de 1755 enquanto outros eventos extremos, como tempestades, é excluída através de considerações hidrodinâmicas. A utilização de uma abordagem multidisciplinar de alta resolução, como a análise multivariada da composição mineralógica da areia e as características microtextuais em superfícies de grão de quartzo, suportam a evidência sobre a origem tsunamigénica dos níveis previamente definidos nas sondagens estudadas no âmbito do projecto ASTARTE, embora não seja visível nenhum vestígio evidente de acarreio terrígeno. O carácter heterogéneo e misto dos depósitos de plataforma correspondentes ao tsunami de 1755 de Lisboa, associados a determinadas condições hidrodinâmicas, sugerem que as subunidades relacionadas com diferentes incursões de ondas de tsunamis e fases de retorno não conseguem serem preservadas em ambientes de plataforma, semelhantes aos da área de estudo. Além disso, diferenças espaciais de deposição de sedimentos de tsunamis foram encontradas na área de estudo através das diferenças na média granulométrica, composição da areia e através do cálculo das velocidades de corrente horizontais. A cxonjugação de vários indicadores como os utilizados neste trabalho permite ampliar ainda mais o conjunto de ferramentas para a identificação de níveis de paleo-tsunami e avançar com novos estudos sobre depósitos de tsunamis no domínio da plataforma continental. Para uma melhor compreensão da dinâmica de sedimentação de tsunamis em regiões de plataforma externa, sugere-se o estudo de várias sondagens localizadas ao longo de transectos, parecendo a plataforma sul de Portugal uma área de estudo promissora. Os tsunamis representam um dos riscos naturais com maior impacte para as zonas costeiras, densamente povoadas. Considerando a subida global do nível do mar, o risco potencial envolvido neste tipo de evento extremo pode mesmo vir a aumentar. Neste contexto, compreender a natureza dos processos relacionados com os tsunamis é crucial para a implementação de medidas de mitigação apropriadas, em simultâneo com um maior envolvimento da população, tanto a nível do conhecimento como da preparação para este tipo de eventos. Atualmente, o conhecimento sobre os depósitos sedimentares resultantes de eventos energéticos (tempestades, tsunamis) na plataforma continental, e em particular na plataforma externa (>60m), é ainda limitado, sendo a compreensão dos processos envolvidos, como a erosão de sedimentos de fundo por correntes de retorno (“backwash”), fundamental para a sua identificação e caracterização. Estas correntes de retorno podem arrastar material terrestre e costeiro e transportá-lo até profundidades de plataforma continental externa. Neste ambiente marinho, é mais provável que os depósitos de tsunamis sejam melhor preservados do que nas áreas terrestres. No entanto, até muito recentemente, os estudos sedimentológicos relativos à identificação e caracterização de eventos de tsunami em registos sedimentares, centravam-se nos depósitos localizados “onshore”. Mas se por um lado a preservação dos depósitos de tsunami será melhor que em ambiente terrestre, as diferentes caraterísticas geológicas regionais, como a batimetria e as fontes sedimentares disponíveis, tornam a identificação dos níveis correspondentes aos eventos de tsunami mais complexa em ambiente de plataforma. Nesse contexto, a utilização de um conjunto de indicadores diferentes e relativos a várias áreas de estudo é crucial para identificar e caraterizar os níveis de tsunamis. No presente estudo, a importância/impacte do tsunami de Lisboa de 1755 e a informação histórica e científica existente foram consideradas bons requisitos para se avançar um pouco mais no estudo de depósitos de tsunami localizados “offshore”. Assim, tendo por objetivo a confirmação dos níveis identificados com origem em tsunami, utilizaram-se, como base de estudo, três sondagens (M106, M107 e POP2) colhidas na plataforma continental externa a oeste de Faro (entre profundidades compreendidas entre 57 e 91 m). Foram utilizados vários indicadores sedimentológicos e as análises que foram realizadas com intervalo centimétrico incluíram, além da granulometria, o estudo composicional da fração arenosa e as características microtexturais das superfícies dos grãos de quartzo. Pretendeu-se assim, encontrar possíveis diferenças entre os 'níveis de tsunami' e a sedimentação normal de plataforma continental, resultantes tanto dos diferentes processos de sedimentação como da origem do material envolvido. Para isso, foram elaborados modelos de idades para cada sondagem, com base nas taxas de sedimentação inferidas a partir dos resultados de 14C e de 210Pb e usando estatísticas baiesianas. Estes modelos permitiram a correlação dos níveis anteriormente identificados como de “alta energia”, com o evento do tsunami de 1755 CE. Além disso, considerações teóricas relacionadas com a profundidade limite da agitação marítima discutidas no presente trabalho excluem outros possíveis eventos extremos como tempestades e inundações na deposição dos níveis em questão. Por conseguinte, é muito provável que estes correspondam aos níveis de tsunami decorrente do sismo de 1755 que afetou grandemente as zonas do Algarve e de Lisboa. Apesar desta correlação, não se encontraram evidências significativas e claras de material transportado pelas ondas de retorno, com o carácter terrígeno que à partida se poderia esperar, como, por exemplo, maior abundância de madeira ou fragmentos de material rochoso derivado do continente. No entanto, a análise multivariada da análise composicional da areia revelou pequenas, mas distinguíveis diferenças entre os sedimentos relacionados com o tsunami e a sedimentação de fundo da plataforma continental. Por outro lado, verificou-se um aumento significativo de “superfícies frescas” e um aumento ligeiro de “marcas de percussão” nos grãos de quartzo dos níveis correspondentes ao tsunami. Estas caraterísticas apoiam a hipótese de uma sedimentação de diferentes caraterísticas nos níveis relacionados com o tsunami e os correspondentes ao regime de sedimentação normal de plataforma. Nos níveis identificados como relacionados com o tsunami, a composição da areia apresenta um aumento de fragmentos de conchas em comparação com a sedimentação de fundo. Além disso, essas camadas tsunamigénicas exibem uma tendência decrescente na média granulométrica da amostra total (sequências granulo-decrescente), apesar da média da fracção arenosa não mostrar nenhuma variação. Exceção feita, no entanto, para uma das sondagens (M107) na qual essa tendência é visível quer na amostra total quer unicamente na fração arenosa. A componente arenosa desta sondagem apresenta uma maior percentagem de grãos terrígenos do que as duas outras sondagens o que explica provavelmente que na camada tsunamigénica a mesma apresente um aumento de percentagem da mica na parte superior dos níveis de tsunami e não um aumento de percentagem nos fragmentos da conchas como observado nas duas sondagens da plataforma externa. A simulação hidrodinâmica da corrente de retorno do tsunami efetuada no presente trabalho implica a existência de uma contribuição dos sedimentos da zona costeira entre Faro e Quarteira pertencente ao Sistema de Barreiras da Ria Formosa. Isto pode explicar o fraco sinal da componente terrígena nos níveis de tsunami, uma vez que o transporte de sedimentos exclusivamente de origem continental é inibido devido ao carácter protetor do sistema de ilhas barreiras da Ria Formosa que não permitiu o avanço da onda de tsunami para o interior. As diferenças das secções estudadas entre sondagens podem ser explicadas pelas diferenças espaciais de deposição sedimentar do tsunami e pelas diferentes velocidades nos respetivos locais a diferentes profundidades. O carácter heterogéneo geral detetado dos prováveis depósitos do tsunami de 1755, juntamente com os resultados do modelo hidrodinâmico, sugerem que as subunidades definidas e relacionadas com diferentes incursões de ondas de tsunamis e fases de retorno não são suscetíveis de serem preservadas em ambientes semelhantes aos da plataforma externa do sul de Portugal. O estudo multidisciplinar utilizado neste trabalho alarga a possibilidade de identificação/caraterização de depósitos de tsunamis em ambiente de plataforma, permitindo assim estimar os intervalos de recorrência dos mesmos em estudos que tenham por base registos sedimentares em ambientes de plataforma semelhantes à estudada. Também se contribuiu para um melhor entendimento/conhecimento da dinâmica de sedimentação de um evento de tsunami numa plataforma continental, sendo, no entanto, necessário mais e melhores estudos nesta área, tendo por base o estudo de várias sondagens localizadas em transetos perpendiculares à costa e em áreas com inundações máximas como, por exemplo, a conhecida área de estudo do tsunami Boca do Rio, no sul do Algarve. Em geral, a plataforma do sul de Portugal parece ser uma área muito boa para estudos sobre processos de sedimentos tsunamigénicos.
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22

McManus, Andrew. "Burial diagenesis and Mississippi Valley-type mineralization in the upper Devonian reef complexes of the Lennard Shelf, Canning Basin, Western Australia." Thesis, 1991. http://hdl.handle.net/2440/112775.

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The aim of this study is to approach the problem of the timing of mineralization in MVT deposits in the context of the diagenetic evolution of the Devonian reef complexes of the Lennard Shelf. These carbonates were subject to two important burial diagenetic events, Late Devonian-Early Carboniferous and Permian-Cenozoic. The region of main interest in this thesis is Billiton's Fossil Downs exploration licence in the Fossil Downs and Brooking Springs Station areas.
Thesis (M.Sc.) -- University of Adelaide, National Centre for Petroleum Geology and Geophysics, 1992
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