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Dissertations / Theses on the topic 'Intrusions (Geology)'

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Published: 4 June 2021

Last updated: 29 July 2024

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1

Dupee, Matthew E. "Porphyroblast Kinematics and Crenulation Cleavage Development in the Aureole of the Mooselookmeguntic Pluton, Western Maine." Fogler Library, University of Maine, 2005. http://www.library.umaine.edu/theses/pdf/DupeeME2005.pdf.

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2

Magee, Craig. "Emplacement of sub-volcanic cone sheet intrusions." Thesis, University of Birmingham, 2011. http://etheses.bham.ac.uk//id/eprint/3042/.

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Sub-volcanic intrusive networks, of which cone sheets are recognised as a major constituent, control volcano growth and eruption style. The accepted cone sheet model is that these confocally dipping intrusions originate from an unexposed central magma chamber through dip-parallel magma flow. However, the emplacement mechanism of cone sheets has remained poorly understood. The classic ~58 Ma cone sheet swarm of Ardnamurchan, NW Scotland, offers an excellent opportunity to further resolve the emplacement dynamics of cone sheets through studying their magma flow. Structural measurements and anisotropy of magnetic susceptibility (AMS) analyses have constrained a lateral magma flow regime, consistently oriented NW-SE, in the majority of the Ardnamurchan cone sheets. This is not consistent with previous emplacement models. In this thesis, it is suggested that emplacement of the Ardnamurchan cone sheets occurred through the deflection of laterally propagating, NW-SE trending regional dykes, sourced from laterally adjacent magmatic systems (likely the Palaeogene Mull central complex). Field observations highlight the importance of host rock structure and interference between locally compressional and regional extensional stress fields in controlling intrusion geometry. Implicitly, edifice construction and potential eruption precursors observed at a volcano may instigate, or result from, magmatic activity in laterally adjacent volcanic systems.

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3

Szarawarska, Ewa. "Origin of large-scale sandstone intrusions : insights from subsurface case studies and numerical modelling." Thesis, Available from the University of Aberdeen Library and Historic Collections Digital Resources, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?application=DIGITOOL-3&owner=resourcediscovery&custom_att_2=simple_viewer&pid=53388.

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Thesis (Ph.D.)--Aberdeen University, 2009.
With: 3D seismic characterization of large-scale sandstone intrusions in the lower Paleogene of the North Sea: completely injected vs in situ remobilized saucer-shaped sand bodies /E. Szarawarska ...et al. In review, Basin Research. Special Issue. Includes bibliographical references.

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4

Sarkar, Arindam. "Isotopic geochemistry of mafic intrusions and related sulfide mineralization Uitkomst and Kabanga, Africa and the Lady of the Lake intrusion, Montana /." [Bloomington, Ind.] : Indiana University, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3332475.

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Thesis (Ph.D.)--Indiana University, Dept. of Geological Sciences, 2008.
Title from PDF t.p. (viewed on May 14, 2009). Source: Dissertation Abstracts International, Volume: 69-09, Section: B, page: 5279. Adviser: Edward M. Ripley.

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5

Al-Jawadi, A. F. "Minor igneous intrusions of the Lake District : geochronology, geochemistry and petrology." Thesis, University of Newcastle Upon Tyne, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376308.

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6

Pattison, Christopher Ian. "Igneous intrusions in the Bowen Basin." Thesis, Queensland University of Technology, 1990. https://eprints.qut.edu.au/35967/1/35967_Pattison_1990.pdf.

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Igneous intrusions, in the form of stocks, sills and dykes are abundant in the Bowen Basin. They are predominantly Early Cretaceous in age, exclusively epizonal in origin and range in composition from dolerite to granodioriteldacite. All rock units within the basin, up to and including the Clematis Group, are intruded to some degree. This study assesses the distribution, form, petrology and mode of emplacement of plutons, igneous sills and dykes occurring in the Bowen Basin, and considers their relationship to the prevailing structure. The tectonic implications of the findings are then assessed. Igneous sills occur in two geographically distinct domains, one in the northern Bowen Basin and the other in the central Bowen Basin. The sills emanated from pre-existing, north to north-northwest trending reverse faults, and preferentially intruded coal seams. The boundaries to sill intrusion are marked by major northeast trending basement structures. These basement structures occur at regular intervals throughout the basin, and correspond with the localisation of plutonic and dyke activity, anomalous structural disturbance, and changes in the gross structure of the basin. They are interpreted as transfer faults that were inherited from an Early Permian, basin-forming extensional episode. Petrological evidence indicates that the plutons and sills occurring in the northern Bowen Basin are petrogenetically related, and that a progressive variation in their chemistry occurs across the axis of the basin from east to west. Intrusions in the east belong to the calc-alka1ine rock suite, while those in the west belong to the syenitic suite. This transition is inte1preted in terms of increased crustal contamination as the magma migrated from a source area to the east along a buried, shallow-dipping detachment surface that extends under the basin. This detachment was inherited from the above mentioned extensional phase and is intimately linked to structures that penetrate up-section through the basin succession. Reactivation of the transfer faults during the Early Cretaceous initiated the emplacement of dykes, and the synchronous development of northeast trending normal and wrenchstyle faults. The dykes exhibit characteristics that indicate they were self-propagating, and can be regarded as good palaeostress indicators. This phase corresponded with a major compressional event that involved the reactivation of pre-existing thrust structures, deformation of the Folded Zone and eastern margins of the Nebo Synclinorium and Mimosa Syncline, and the rapid preferential uplift of the central Bowen Basin region.

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7

Christodoulou, C. "Petrology of the plutonic rocks of the Macquarie Island Complex /." Title page, contents and abstract only, 1990. http://web4.library.adelaide.edu.au/theses/09PH/09phc556.pdf.

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8

Wong, Lai-man Kennis. "Geochemistry of mafic dykes from the Discovery Bay granitic pluton, Hong Kong." Click to view the E-thesis via HKUTO, 2004. http://sunzi.lib.hku.hk/hkuto/record/B42577688.

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9

Sigler, Joshua T. "The metamorphic and structural evolution of the Davis Peak area, northern Park Range, Colorado." Laramie, Wyo. : University of Wyoming, 2008. http://proquest.umi.com/pqdweb?did=1798480831&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.

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10

Lassen, Birgitte. "Petrogenesis of the late Archean Quetico alkaline suite intrusions, Western Superior Province, Canada." Thesis, University of Ottawa (Canada), 2004. http://hdl.handle.net/10393/10684.

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A suite of 13 late Archean subalkaline to alkaline intrusions were studied by major and trace element geochemistry and neodymium, hafnium and lead isotopic methods. The intrusions (2683 - 2678 Ma) are located in the Quetico metasedimentary belt, western Superior Province, and include pyroxene hornblendite, diorite, monzonite, syenite and carbonatite. The samples display arc-like trace element patterns with high Cs, Ba, Sr and light rare earth element abundances and low Zr, Hf, Nb, Ta and Ti. Neodymium and hafnium isotope data reflect derivation from a depleted mantle source with minor contribution from an enriched source. Lead isotope ratios from K-feldspar separates are dominated by a slab fluid or crustal component. Quantitative modeling of trace element and isotope ratios illustrates that a metasomatic event shortly before melting produced the main geochemical signatures, but a contribution from an older crustal source is also required to explain the range in data. Melting models based on rare earth element variations suggest that melting occurred over a range of pressures or took place in the garnet spinel transition zone. The intrusive complexes can be subdivided into two groups on the basis of high field strength element distribution, which appears to reflect mantle heterogeneities resulting from differences in metasomatic processes. The most abundant group exhibits super-chondritic Nb/Ta and excess Nb relative to magmas produced by melting of a fluid metasomatized mantle. These characteristics are in accord with metasomatism by silicic melts that have left rutile in the residue and the metasomatic agent is thought to be a mixture of slab-derived fluids and melts. The trace element chemistry of the remaining intrusions reflects a source affected by fluid metasomatism. Carbonatite constitutes a minor part of the Beaverhouse Lake intrusion. Qualitative major and trace element modeling suggests that the carbonatite formed by carbonate-silicate liquid immiscibility. The carbonatite is characterized by highly depleted hafnium isotopic signatures, which are interpreted to result from a previous episode of carbonate metasomatism. Modeling of Lu-Hf partitioning during silicate-carbonate liquid immiscibility suggests that anomalously high hafnium isotopic ratios should develop with time in the carbonate phase, which has potentially important implications for carbonate metasomatism.

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11

Patton, David James Stanley. "The petrography and petrochemistry of the Tertiary basic hypabyssal intrusions of northeast Ireland." Thesis, Queen's University Belfast, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356968.

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12

Sun, Weihua. "The neoproterozoic Yanbian group and associated plutons in the western Yangtze block, SW China." Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B41897158.

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13

Hay, Susan Vivienne. "Some geochemical and isotopic studies of the Insch, Huntly and Belhavie intrusions, NE Scotland." Thesis, Royal Holloway, University of London, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.271593.

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14

Gulick, Virginia Claire. "Magmatic intrusions and hydrothermal systems: Implications for the formation of Martian fluvial valleys." Diss., The University of Arizona, 1993. http://hdl.handle.net/10150/186325.

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This dissertation investigates the possible role of hydrothermally driven groundwater outflow in the formation of fluvial valleys on Mars. Although these landforms have often been cited as evidence for a past wanner climate and denser atmosphere, recent theoretical modeling precludes such climatic conditions on early Mars when most fluvial valleys formed. Because fluvial valleys continued to form throughout Mars' geological history and the most earth-like stream valleys on Mars formed well after the decline of the early putative earth-like climate, it may be unnecessary to invoke drastically different climatic conditions for the formation of the earliest stream valleys. The morphology of most Martian fluvial valleys indicates formation by ground-water sapping which is consistent with a subsurface origin. Additionally, many Martian fluvial valleys formed on volcanoes, impact craters, near fractures, or adjacent to terrains interpreted as igneous intrusions; all are possible locales of vigorous, geologically long-lived hydrothermal circulation. Comparison of Martian valley morphology to similar features on Earth constrains valley genesis scenarios. Volumes of measured Martian fluvial valleys range from 10¹⁰ to 10¹³ m³. Based on terrestrial analogs, total water volumes required to erode these valleys range from -10¹⁰ to 10¹⁵ m³. The clustered distribution of Martian valleys within a given terrain type, the sapping dominated morphology, and the general lack of associated runoff valleys all indicate the importance of localized ground-water outflow in the formation of these fluvial systems. An analytic model of a conductively cooling cylindrical intrusion is coupled with the U.S. Geological Survey's numerical ground-water computer code SUTRA to evaluate the magnitude of ground-water outflow expected from magmatically-driven hydrothermal systems on Mars. Results indicate that magmatic intrusions of several 10² km³ or larger can provide sufficient ground-water outflow over periods (several 10⁵ years) required to form Martian fluvial Valleys. Therefore, a vastly different climate on early Mars may not be necessary to explain the formation of the observed Valleys. Martian hydrothermal systems would have also produced long-lived sources of near-surface water; these localized regions may have provided oases for any microbial life that may have evolved on the planet.

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15

Gestsson, Einar Bessi. "Geothermal Potential of Sub-Volcanic Intrusions in a Typical Caldera Setting." Thesis, Uppsala universitet, Mineralogi, petrologi och tektonik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-354072.

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Sub-volcanic intrusions can form an extensive network of sills, dikes and other intrusion types that make up a plumbing system beneath volcanoes. Such intrusions are the heat source for high-temperature geothermal systems in volcanic areas and therefore, it is of great importance to study them in relation to geothermal exploration and production. In this thesis a part of the plumbing system of Breiðuvík caldera, an eroded central volcano in northeastern Iceland, is studied. A set of magmatic intrusions showing a great range in size and shapes, is exposed in Leirfjall, a mountain composed of the eroded caldera infill of the Breiðuvík volcanic system. Data from these intrusions and their host rock is used as the foundation for numerical modeling using finite element method (FEM) constructed in this thesis. The numerical modeling assumes heat transfer in porous media including conduction and convection where fluid flow is governed by the Darcy‘s law. The aims of it is to compare the cooling times of different intrusions and the temperature distribution caused by intrusions of different sizes and shapes. To obtain input parameters for the numerical modeling, a thermometry study based on the mineral chemistry of the magmatic intrusions in Leirfjall is conducted and the thermal and physical properties of the sedimentary host rock are estimated, while literature values are used for basaltic lava and hyaloclastite host rocks for comparison. The results of the numerical modeling suggest that higher maximum values of increased temperature are reached above one thick intrusions compared to multiple thinner intrusions. When comparing dikes and sills, the dikes raise the maximum temperature of the host rock more than the sills, while the sills raise the average temperature above the intrusions more than dikes. Results of the estimated heat transfer from an arrangement of intrusions similar to what is observed in Leirfjall suggests that a significant increase in maximum increased temperature caused by the intrusions would be short-lived, while the average increase would still be constant over a longer time. Despite of the simplified structure of the numerical models it is the hope that they will provide inspiring data for further research and contribute to a better understanding of the relationship between the shallow magmatic intrusions and geothermal systems.
Vulkaner är en viktig energikälla i många länder runt om i världen. Geotermisk vätska och ånga av högtemperatur som finns i vulkanområden kan utnyttjas för bland annat elproduktion och fjärrvärme. Värmekällan till de geotermiska områdena är magma som ligger ytligt i jordskorpan. All magma når inte ytan i utbrott, utan stannar under vulkanen i form av magmaintrusioner. Intrusionerna av olika former och storlekar utgör ett nätverk som tillsammans utgör vulkanens magma transportsystem. I denna studie studeras en uppsättning av magmaintrusioner på nordöstra Island. Intrusionerna har en gång befunnit sig längre ner i jordskorpan under ett aktivt vulkanområde men exponeras nu vid ytan på grund av glacial erosion. Intrusionernas storlek och form varierar, men de flesta återfinns som gångar, både vertikala och horisontella. När en magmatintrusion bildas värms omkringliggande berggrund och grundvatten upp. Studiens fokus är att undersöka hur temperaturfördelningen i omgivningen skiljer sig vid en stor intrusion jämfört med flera mindre intrusioner med totalt samma volym. Även effekten från olika typer av berggrund runt intrusionerna studerades genom att jämföra temperaturfördelningen och kylningstiderna för intrusioner i tre vanliga bergarter. Numerisk modellering användades för att besvara dessa frågor. Bergarternas fysiska och termiska egenskaper krävdes som ingångsparametrar för den numeriska modelleringen. Parametrana uppskattades genom laboratorieexperiment och termometriberäkningar från fältprover. Värden från publicerat material användes också i modelleringen. Resultaten från den numeriska modelleringen antyder att högre maximivärden för temperaturen nås i berget över en stor, enskild intrusion jämfört med flera mindre intrusioner. När man jämför vertikala og horisontella gångar, ökar de vertikala gångarna berggrundens temperatur mer än de horisontella, medan medeltemperaturen ökar mer över horisontella gångar än i vertikala gångar. Trots den numeriska modellens förenklade struktur är förhoppningen att den nya datan kan inspirera vidare forskning, och bidra till en bättre förståelse om förhållandet mellan grunda magmaintrusioner och geotermiska system.

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16

O’Brien, Catherine. "The petrogenesis and geochemistry of the British Caledonian granites, with special reference to mineralized intrusions." Thesis, University of Leicester, 1985. http://hdl.handle.net/2381/8431.

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The Caledonian fold belt of Britain forms part of a major orogenic belt now to be found along the east coast of north America (Appalachians), northeast Greenland, the British Isles and western Scandinavia. Intrusive granitic rocks of Caledonian age are found in all parts of the fold belt, on both sides of the suture, which, in the British Isles is thought to pass along a line through the Solway Firth. The British section of the Caledonian fold belt has been extensively studied and mapped, and to a wealth of detail has accumulated on the metamorphic, structural and tectonic aspects of the fold belt. However there has been no previous comprehensive geochemical study of the granitic intrusive rocks, although some individual intrusions have been examined in detail. The aim of this project was to produce a comprehensive body of major and trace element data on the Caledonian granitoids which would provide a regional framework witin which the petrogenesis of the granites could be considered, both individually and collectively, along with the effects of element distributions during fractional crystallization, hydrothermal alteration and mineralization. [Taken form the thesis Introduction]

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17

Pang, Kwan-Nang. "Origin of the permian panzhihua layered gabbroic intrusion and the hosted Fe-Ti-V oxide deposit, Sichuan Province, SW China." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B39634000.

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18

Tuitt, Natasha R. T. "4D interpretation of texture and architecture of a coarse grained slope channel system using automated statistics from high resolution outcrop photography." Thesis, University of Aberdeen, 2014. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=218284.

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The building blocks of a sedimentary system are essential inputs into studies of reservoir character and comparisons with other sedimentary systems. Yet, our current knowledge of the building blocks of deep water slope channel deposits is still largely speculative. A quantitative approach has been utilised in order to analyse a host of lithological data and objectively identify these sedimentary components. The laterally-extensive and gently-dipping continental slope deposits of the San Fernando Channel System, Baja California, provide the required control on sub-seismic-scale temporal and lateral variations of lithofacies and 3D architecture. High resolution photo-panoramas (with better than 2mm accuracy) of the prominent conglomeratic component of the succession were collected from various key parts of the outcrop. Image analysis of segments extracted from the photo-panoramas generates key parameters for comparison of texture and fabric of conglomerates, such as clast to matrix ratio, major axis length and relative orientation. Statistical analysis of these data enabled the erection of an objective lithofacies scheme for the gravel fraction, the grouping of lithofacies into objectively-defined assemblages, and the establishment of models for the lateral and stratigraphic distributions of these assemblages. 12 lithofacies were objectively identified through hierarchical cluster analysis of 4 quantitative lithological parameters. Statistical analyses indicate significant differences in diversity in the lithofacies assemblages between the early and later parts (termed Stage 1 and Stage 2) of a channel complex set (sensu Sprague, et al., 2002), and to a lesser extent between marginal and axial parts of the system. These can be related to spatial differences and temporal changes in the nature of the turbidity currents flowing through the channel system. Gravelly units become more organised and less diverse with time in one CCS, and each successive CCS more organised at earlier stratigraphic levels than the next, except for the last CCS which is interpreted as influenced by a tectonic paroxysm. These seemingly autocyclic changes in organisation are interpreted as process-responses to changes in equilibrium profile as the nature of confinement changes with the infilling of an initial erosional confinement, to confinement by a master levee and gradual infilling through the evolution of each CCS.

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19

Karykowski, Bartosz. "New approaches in understanding layered intrusions : field-based and analytical evidence from the Bushveld and Monchegorsk complexes." Thesis, Cardiff University, 2017. http://orca.cf.ac.uk/108748/.

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The formation of layered intrusions remains one of the most important, yet unresolved issues in the study of mafic-ultramafic systems, although they are of major economic significance, hosting more than 80 % of the world's platinum-group element (PGE) resource. In many layered intrusions, PGE mineralisation is associated with stratigraphic intervals that are characterised by pronounced igneous layering. Thus, the origin of layering and the emplacement mechanism of individual layers are closely related to the formation of PGE deposits. In this study, field-based and analytical evidence from the Bushveld Complex of South Africa and the Monchegorsk Complex in Russia is used to gain a better understanding of the small- and large-scale processes associated with the emplacement of layered intrusions. Detailed examination of drill core and field exposures suggest that sill-like intrusions of crystal mushes play an important role in the formation of layered intrusions, especially in the lower ultramafic portions of large complexes. In contrast, the in situ Sr isotope analysis of plagioclase from the upper portion of the Bushveld Complex indicates that the more mafic portions may also crystallise in situ from crystal-poor magmas, which can also undergo mixing. Moreover, mineralogical and microtextural work based on high-resolution elemental mapping highlights the importance of melt migration at different stages of cumulate solidification as a consequence of displacement by convecting interstitial liquids and compaction. Further, broadly stratiform PGE mineralisation in the Monchegorsk Complex cannot always be explained by a classic PGE reef model, in which the mineralised horizon marks the transition from sulfide-undersaturated to sulfide-saturated conditions. It is more likely that preformed sulfides were entrained in crystal mushes and emplaced into a semi-consolidated cumulate pile at different levels of the layered intrusion. Ultimately, thermal modelling shows that a multi-stage emplacement history of a complex should be regarded as highly prospective with respect to PGE-Ni-Cu mineralisation.

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20

Fletcher, Timothy Andrew. "The geology, mineralisation (Ni-Cu-PGE) and isotope systematics of Caledonian mafic intrusions near Huntly, NE Scotland." Thesis, University of Aberdeen, 1989. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=88127.

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The Caledonian mafic and ultramafic intrusions of the Grampian region of N.E. Scotland are a suite of synorogenic tholeiitic plutons of mid-Ordovician Age. They include layered cumulates, granular gabbronorites, quartz biotite norites and xenolithic contact facies lithologies. They postdate two regional deformation events in the enclosing Late Precambrian Dalradian metasediments, but are themselves locally deformed by a major regional ductile shear zone system. A detailed study of the Huntly-Knock area was undertaken combining geological mapping, petrological, geochemical and stable isotope techniques. In the study area, layered peridotitic to gabbroic cumulates, transitional cumulate types, granular gabbronorites quartz biotite norites and complex xenolithic contact facies rock types are present as a series of disrupted bodies formed by multiple intrusive events and subsequent deformation of a laccolithic and sheeted intrusive complex. Progressive cryptic fractionation trends are observed from basal peridotites to quartz biotite norites in the 'roof' of the intrusion. The chemistry and mineralogy of the rocks places them in the Lower and Middle Zone of the regional Younger Basic 'stratigraphy', although isolated pockets of Upper Zone may occur. Fine grained disseminated Fe-Ni-Cu sulphides are widespread throughout the mafic and ultramafic rock types. Richer sulphide concentrations locally occur as: gabbronorite hosted disseminated to massive bodies in the structurally complex, Littlemill-Auchencrieve contact zone; disseminated horizons within cumulates; disseminated to submassive graphite-rich pods in pyroxenitic pegmatites. The sulphide assemblage is dominated by pyrrhotite with minor pentlandite and chalcopyrite. Sulphide textures are attributed to magmatic processes with local modification by ductile deformation and hydrothermal reworking. Field, textural and Cu/Cu+Ni relations of certain submassive-massive sulphides is consistent with their derivation from an ultramafic parent. Maximum Ni and Cu levels are 3.02% and 6.46% respectively. The highest combined Pt+Pd+Au values occur in remobilised net sulphide (574ppb) and graphitic pyroxenite (700ppb). These metal values are generally low and comparable to other orogenic Caledonian intrusions. Sulphide immiscibility occurred many times during cooling of the tholeiitic parent magma(s), however early sulphide melts are generally of most economic importance. While there is abundant evidence for magma/country rock interaction, only locally is there evidence for involvement of metasediment sulphur, the system being dominated by a magmatic signature. In the Littlemill-Auchencrieve contact zone, crustal involvement may have been the principal factor controlling sulphide immiscibility. Subsequent hydrothermal reworking within ductile shear zones under amphibolite facies metamorphic conditions modified metal values. Depletion, especially of Au, Pt and Pd was mainly observed but local significant zones of enrichment may also be present.

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21

Buick, Ian S. "The petrology and geochemistry of granitic rocks from the Entia domal structure, Harts Range, eastern Arunta Block, Central Australia /." Title page, contents and abstract only, 1985. http://web4.library.adelaide.edu.au/theses/09SM/09smb932.pdf.

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22

Tettelaar, Tanya Anne. "Emplacement history of the Pearly Gates anorthosite pluton and spatially related Tessiarsuyungoakh intrusion, and metamorphic petrology of the adjacent Tasiuyak paragneiss, northern Labrador /." Internet access available to MUN users only, 2004. http://collections.mun.ca/u?/theses,61302.

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23

Hulley, Vierah. "Reactions between country rock xenoliths and the magma of Uitkomst Complex, with implications for the origin of the sulphide mineralisation." Pretoria : [s.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-05282008-101011.

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24

Abdel-Rahman, Abdel-Fattah Mostafa. "Plutonism and tectonic evolution of the Ras Gharib segment of the northern nubian shield, Egypt." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=73998.

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Lalonde, André E. "The intrusive rocks of the Hepburn metamorphic-plutonic zone of the central Wopmay Orogen, N.W.T. /." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=76906.

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26

Sun, Weihua, and 孙卫华. "The neoproterozoic Yanbian group and associated plutons in the westernYangtze block, SW China." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B41897158.

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27

Cooper, Jennifer Rebecca. "Igneous intrusions and thermal evolution in the Raton Basin, CO-NM contact metamorphism and coal-bed methane generation /." Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/4606.

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Thesis (M.S.)--University of Missouri-Columbia, 2006.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (February 6, 2007) Includes bibliographical references.

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28

Hart, Craig Joseph Ronald. "Mid-Cretaceous magmatic evolution and intrusion-related metallogeny of the Tintina Gold Province, Yukon and Alaska." Connect to this title online, 2004. http://theses.library.uwa.edu.au/adt-WU2005.0062/.

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29

King, John Frederick. "Magmatic Evolution and Eruptive History of the Granitic Bumping Lake Pluton, Washington: Source of the Bumping River and Cash Prairie Tuffs." PDXScholar, 1994. https://pdxscholar.library.pdx.edu/open_access_etds/4765.

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The 25 Ma Bumping Lake pluton ranges in composition from quartz diorite to granite with the granitic facies comprising approximately 90% of the pluton's surface area. The granite may be classified as calcalkaline, peraluminous and I-type with some Stype characteristics. A late-stage, mafic-poor facies fills cooling related extensional fractures. The pluton was passively emplaced into the Ohanapecosh Formation at a shallow level in the crust. Contact relationships vary from sharp where the contact is vertical to gradational at the roof of the pluton. Where gradational, stoped xenoliths from the roof of the pluton increase in size, angularity and retain more of their primary textures as the contact is approached. Spacial trends in major and trace elements support the interpretation that xenoliths were stoped and assimilated into the melt The predicted Rayleigh number for the pluton when molten is 107 and the predicted Reynolds number is approximately 10-9. Based on these values, the magma of the pluton probably did not convect, and if it did, convection was weak and not a significant process. Based on variations in Eu/Eu* and Sr values, plagioclase fractionation was an important process in the petrogenesis of the pluton. Additionally, fractionation of accessory minerals rich in light rare-earth elements (LREE) resulted in successive depletion of LREE with progressive differentiation. Two separate regions of the pluton are highly differentiated as indicated by high Si02 values, high Rb/Zr ratios, and low Zr and Ti02 values. Mapping by the author indicates that the pluton projects beneath the Mount Aix caldera. Dates of three tuffs derived from the caldera are equivalent to the pluton, and two of these tuffs are chemically indistinguishable from the granite facies of the pluton. This implies that the Bumping Lake pluton represents the chilled remains of the magma chamber that fed the Mount Aix caldera.

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Li, Pan. "Architecture and sedimentology of slope channel fills : an outcrop- and subsurface-based study." Thesis, University of Aberdeen, 2017. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=231778.

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Slope channel systems represent significant but highly variable deep-water stratigraphic features and reservoir targets. Variations in architecture and component facies can take place along strike, depositional dip and stratigraphically. A better understanding of these variations permits improved sedimentological and architectural models. By integrating two outcrops (San Clemente, California and Baja California, Mexico) and one subsurface example (offshore Nile Delta), this study provides an opportunity to investigate cross-channel asymmetry, stratigraphic evolution and variability, vertical facies trends, and controls of slope channel systems. This study demonstrates that cross-channel asymmetry in facies and architecture is a lithology- and scale-independent feature, and preferentially occurs at channel bends and in the upper part of slope channel systems. Facies and architectural asymmetry are generally expressed as amalgamated, coarser-grained deposits displaced to the steeper channel edge (outer bend), and finer-grained deposits dominate towards the gentler channel edge (inner bend). A comparison of the systems exposed in Mexico and buried in the subsurface reveals a similar evolutionary trend, from initial sediment erosion/bypass, through early-stage laterally amalgamated channels, late-stage sinuous channels with levees/terraces, and final abandonment. However, pronounced variations exist in the late stage (e.g., presence or absence of lobes), and abandonment stage (e.g., presence or absence of MTDs plugging and channel avulsion). Additionally, for the first time, this study quantitatively demonstrates that early-stage and late-stage architectural elements are characterized by distinct patterns in preferred vertical facies transitions, based on Markov chain analysis of vertical successions. This study also suggests that both extrabasinal factors (e.g., relative sea-level) induced flow energy cycles and intrabasinal factors (e.g., folding and faulting, MTDs, channel bends) can exert a significant control on the architecture and/or evolution of slope channel systems.

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Elias, Ralph Thomas. "Cumulus processes and melt-migration in layered intrusions and the use of image analysis to quantify microscopic textures in cumulates." Thesis, University of Liverpool, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316637.

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This thesis presents three studies carried out to investigate the relationship between small scale structures and large scale processes in layered intrusions. The first is a field-based study from the Eastern Layered Series of the Rhum intrusion. Lateral variations were found to be significant in the allivalite of unit 12 on Hallival, and the cumulate stratigraphy was shown to thin by approximately 50% over less than 800 metres down-dip. This thinning was associated with the development of layeringparallel zones of intense deformation and the entire cumulate package is interpreted to have evolved as a sequence of alternating troctolitic and peridotitic mass flows initiated by the intrusion of basaltic melts into marginal cumulates. In addition, a series of gabbroic cumulates were interpreted as preserving melt-migration pathways within still-porous cumulates. Cumulus textures were found to control porosity-permeability relationships in the crystal pile. The effect of anisotropy on the movement of melts was studied. Core material from the Muskox layered intrusion was analysed to constrain compaction and showed it to be a widespread process which reduced melt contents to -10% over cumulate depths of 1000 metres, in less than 600 years. Progressive contamination of Muskox primary melts resulted in a change from olivine-rich to pyroxene-rich cumulates and this lea to an increase in matrix viscosity from <5x10 15 Pa s to -4x1016. The final part of the thesis concentrates on the quantification of interfacial curvature, a parameter which dominates the evolution of textures by surface energy minimization. Software is presented to allow the determination of variations in two dimensional grain boundary curvatures by curve-fitting method using a cubic spline. The software is tested on experimental olivinebasalt aggregates.

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Miggins, Daniel Paul. "Temporal and geochemical insights related to volcanic and plutonic activity within Big Bend National Park, Texas." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2009. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.

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Hart, Craig J. R. "Mid-Cretaceous magmatic evolution and intrusion-related metallogeny of the Tintina Gold Province, Yukon and Alaska." University of Western Australia. Centre for Global Metallogeny, 2005. http://theses.library.uwa.edu.au/adt-WU2005.0062.

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[Truncated abstract] The Tintina Gold Province (TGP) comprises numerous (<15) gold belts and districts throughout interior Alaska and Yukon that are associated with Cretaceous plutonic rocks. With a gold endowment of ∼70Moz, most districts are defined by their placer gold contributions, which comprise greater than 30 Moz, but four districts have experience significant increases in gold exploration with notable discoveries at Fort Knox (5.4 Moz), Donlin Creek (12.3 Moz), Pogo (5.8 Moz), True North (0.79 Moz), and Brewery Creek (0.85 Moz). All significant TGP gold deposits are spatially and temporally related to reduced (ilmenite-series) and radiogenic Cretaceous intrusive rocks that intrude (meta-) sedimentary strata. The similar characteristics that these deposits share are the foundation for the development of a reduced intrusion-related gold deposit model. Associated gold deposits have a wide variety of geological and geochemical features and are categorized as intrusion-centered (includes intrusion-hosted, skarns and replacements), shear-related, and epizonal. The TGP is characterized by vast, remote under-explored areas, unglaciated regions with variable oxidation depths and discontinuous permafrost, which, in combination with a still-evolving geological model, create significant exploration challenges. Twenty-five Early and mid-Cretaceous (145-90 Ma) plutonic suites and belts are defined across Alaska and Yukon on the basis of lithological, geochemical, isotopic, and geochronometric similarities. These features, when combined with aeromagnetic characteristics, magnetic susceptibility measurements, and whole-rock ferric:ferrous ratios define the distribution of magnetite- and ilmenite-series plutonic belts. Magnetite-series plutonic belts are dominantly associated with the older parts of the plutonic episode and comprise subduction-generated metaluminous plutons that are distributed preferentially in the more seaward localities dominated by primitive tectonic elements. Ilmenite-series plutonic belts comprise slightly-younger, slightly-peraluminous plutons in more landward localities in pericratonic to continental margin settings. They were likely initiated in response to crustal thickening following terrane collision. The youngest plutonic belt forms a small, but significant, magnetite-series belt in the farthest inboard position, associated with alkalic plutons that were emplaced during weak extension. Intrusion-related metallogenic provinces with distinctive metal associations are distributed, largely in accord with classical redox-sensitive granite-series. Copper, Au and Fe mineralisation are associated with magnetite-series plutons and tungsten mineralisation associated with ilmenite-series plutons. However, there are some notable deviations from expected associations, as intrusion-related Ag-Pb-Zn deposits are few, and significant tin mineralisation is rare. Most significantly, many gold deposits and occurrences are associated with ilmenite-series plutons which form the basis for the reduced intrusion-related gold deposit model

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Pettigrew, Neil Thomas. "Copper-nickel-platinum group element mineralization and petrogenesis of mafic-ultramafic intrusions in the western Quetico and Wabigoon Subprovinces, northwestern Ontario, Canada." Thesis, University of Ottawa (Canada), 2004. http://hdl.handle.net/10393/26743.

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This project focused on Cu-Ni-PGE mineralization and petrogenesis of mafic-ultramafic intrusions in the western Quetico and Wabigoon Subprovinces of the Superior Province. Two intrusions were singled out for detailed study: the Legris Lake Complex, part of circular series of mafic-ultramafic complexes, which includes the Lac des Iles Complex, located in the Wabigoon Subprovince, and the Samuels Lake Intrusion, part of the Quetico Intrusions, located in the Quetico Subprovince. Legris Lake complex. The Legris Lake Complex is a northeast-trending 7.3 by 3.5 kilometre mafic-ultramafic intrusive complex. It is part of a circular series of mafic-ultramafic complexes, the most notable of which is the Lac des Iles Complex, which is host to Canada's only palladium mine. The Legris Lake Complex consists of mostly gabbroic rocks, but also contains lithologies ranging from anorthosite to wehrlite, and, variety of igneous breccias. The gabbroic rocks vary from melanogabbro to porphyritic leucogabbro. Medium grained, massive, biotite-rich leucogabbro is the predominant exposed variety and probably caps the complex. Samuels Lake intrusion. The Samuels Lake intrusion, ca 2688 +6/-5 Ma, located in the centre of the Quetico Subprovince possesses a northeast-southwest elliptical form (500 m by 250 m) and displays rough concentric zoning with a wehrlite core grading into clinopyroxenite border zone, which has been intruded by later homblendite. Olivine-rich rocks commonly contain blebs of pyrrhotite + chalcopyrite + pentlandite with anomalous PGE values, ranging from 50 to 300 ppb, whereas the clinopyroxenite border zone contains disseminated to blebby PGE-rich Cu-sulphide mineralization. (Abstract shortened by UMI.)

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35

Brown, Connie Lynn. "The construction of a plutonic complex in a continental arc setting the Skookum Butte stock, western Montana /." CONNECT TO THIS TITLE ONLINE, 2008. http://etd.lib.umt.edu/theses/available/etd-05302008-145300/.

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36

Young, David Paul. "The history of deformation and fluid phenomena in the top of the wilderness suite, Santa Catalina Mountains, Pima County, Arizona." Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/558089.

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Van, Bosse Jacqueline Yvonne. "Metamorphism and alteration in the thermal auerole of the McGerrigle Mountains pluton, Gaspé, Québec." Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66061.

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38

Schucker, Dennis Eugene. "Mesozoic igneous intrusions in New England and Quèbec : implications from lead (Pb) isotopes on petrogenesis and mantle sources (Ascutney Mountain, VT; Mont Saint Hilaire, Quèbec; Pliny Complex, NH) /." The Ohio State University, 1992. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487779120909591.

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39

Gallagher, Brookie Jean. "A Comparative Study of the Badger Pass Igneous Intrusion and the Foreland Volcanic Rocks of the McDowell Springs Area, Beaverhead County, Montana: Implications for the Local Late Cretaceous Sequence of Events." Digital Archive @ GSU, 2008. http://digitalarchive.gsu.edu/geosciences_theses/11.

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Intermediate igneous rocks exposed in the Badger Pass area and 3.5 km away in the McDowell Springs area of Beaverhead County, Montana, previously mapped as Cretaceous intrusive (Ki), and Cretaceous undifferentiated volcanics (Kvu) respectively, exhibit little geochemical variation. Trace element, and lead isotope analyses provide strong evidence allowing for a single source. REE patterns, obtained through ID-ICP-MS, are essentially identical. Mineral/melt Eu analyses reveal that Eu behaved predominantly as a divalent cation, refuting an earlier study asserting that trivalent Eu dominated. Data suggest rocks were formed under low oxygen activity conditions, not oxidizing conditions as previously reported. Geochemical data combined with field mapping allow us to establish the temporal relationship between late Cretaceous thrusting, intrusion, and volcanism in this locale. Folding, faulting and thrusting were significantly, if not entirely, completed prior to the commencement of volcanism. Volcanism included contemporaneous thrust plate intrusion, foreland extrusion, and hypabyssal foreland intrusion.

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40

Allen, Charlotte M. "Petrogenesis of the reversely zoned Turtle pluton, Southeastern California." Diss., Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/54480.

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Few plutons with a reversed geometry of a felsic rim and mafic core have been described in the geologic literature. The Turtle pluton of S.E. California is an intrusion composed of a granitic rim and granodioritic core and common microgranitoid enclaves. Field observations, mineral textures, and chemistries, major and trace element geochemistry, and isotopic variability support a petrogenetic model of in situ, concomitant, magma mixing, and fractional crystallization of rhyolitic magma progressively mixed with an increasing volume of andesitic magma, all without chemical contribution from entrained basaltic enclaves. Hornblende geobarometry indicates the Turtle pluton crystallized at about 3.5 kb. A crystallization sequence of biotite before hornblende (and lack of pyroxenes) suggests the initial granitic magma contained less than 4 wt% H₂0 at temperatures less than 780°C. U-Pb, Pb-Pb, Rb-Sr and oxygen isotope studies indicate the terrane intruded by the Turtle pluton is 1.8 Ga, that the Turtle pluton crystallized at 130 Ma, that the Target Granite and garnet aplites are about 100 Ma, and that these intrusions were derived from different sources. Models based on isotopic data suggest the rhyolitic end member magma of the Turtle pluton was derived from mafic igneous rocks, and was not derived from sampled Proterozoic country rocks. Similarity of common Sr and Pb isotopic ratios of these rocks to other Mesozoic intrusions in the Colorado River Region suggest the Turtle pluton and Target Granite have affinities like rocks to the east, including the Whipple Mountains and plutons of western Arizona. P-T-t history of the southern Turtle Mountains implies uplift well into the upper crust by Late Cretaceous time so that the heating and deformation events of the Late Cretaceous and Tertiary observed in flanking ranges did not affect the study area.
Ph. D.

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41

Zoller, Kevin M. "Porphyritic Intrusions of the Helen Zone in the Cove Deposit, Lander County, Nevada." University of Akron / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=akron1398079611.

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42

Strack, Cody M. "Petrologic Study of the Danburg, Sandy Hill, and Delhi Intrusions: Constraints on Magmatism in the Southern Appalachians." Ohio University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1439388136.

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43

Kalaghan, Theresa A. "Deformation in the striped rock pluton, southwest Virginia." Thesis, Virginia Polytechnic Institute and State University, 1987. http://hdl.handle.net/10919/56190.

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The Striped Rock pluton of the late-Proterozoic Crossnore Plutonic-Volcanic suite is located beneath the Fries Thrust zone in the Blue Ridge province of southwest Virginia. The multiphase granite pluton has been affected by episodes of brittle and crystal plastic deformation at both the microscopic and mesoscopic scales. Brittle deformation preceded and postdated crystal plastic deformation. The pluton is cut by pervasive centimeter-scale cataclasite zones and ductile shear zones that vary in width from a few millimeters to several hundred meters. The majority of mylonite zones in the pluton strike east and northeast and are inclined moderately southeast. Cataclasite zones strike northeast and northwest. Deformation is most intense along the southern contact with the Cranberry gneiss where both pluton and country rock are deformed into a northeast-striking zone of mylonitic augen gneiss. The intensity of deformation decreases northwestward. Southeastdirected normal fault displacement is common to east and northeast-trending shear zones. A minor group of northwest-oriented shear zones dip moderately southwest and northeast and show sinistral, strike-slip displacement. Quartz-, chlorite- and stilpnomelane-filled cracks and veins with northeast and northwest trend uniformly overprint mylonite and cataclasite zones of all scales. Microstructure changes progressively with increasing strain. Feldspar grains are cut by at least two generations of mineralized, dilatant microcracks. Minerals precipitated in the early set of microcracks have undergone extensive crystal plastic deformation. Late-stage microcracks are filled with completely undeformed minerals. The spatial distribution of normal fault mylonite zones is geometrically consistent with generation during 1) late-Proterozoic extension, 2) Mesozoic extension, 3) rigid-body rotation during Paleozoic thrusting, or 4) "gravitational collapse" during Paleozoic thrusting. Field and microstructural evidence favor (4). The exact timing of deformation is not, however, well-constrained.
Master of Science

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44

Wong, Lai-man Kennis, and 王麗敏. "Geochemistry of mafic dykes from the Discovery Bay granitic pluton, Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B42577688.

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45

Brown, Kenneth Lee. "Construction of Late Cretaceous, Mid-Crustal Sheeted Plutons from the Eastern Transverse Ranges, Southern California." Thesis, Connect to resource online, 2008. http://hdl.handle.net/1805/1725.

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Thesis (M.S.)--Indiana University, 2008.
Department of Earh Sciences, Indiana University-Purdue University Indianapolis (IUPUI). Advisor(s): Kathy J. Licht. Includes vita. Includes bibliographical references (leaves 149-154).

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46

Gao, Jianfeng, and 高剑峰. "Petrogenesis of permian sulfide-bearing mafic-ultramafic intrusions insoutheast Chinese Altay and east Tianshan, NW China." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2012. http://hub.hku.hk/bib/B49617801.

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The Central Asia Orogenic Belt is one of the largest accretionary orogenic belts in the world. In this belt, many sulfide‐bearing mafic‐ultramafic intrusions occur along faults, including the Kalatongke complex in southeast Chinese Altay and the Huangshandong intrusion in east Tianshan. The Kalatongke complex is a composite body including ~308Ma dioritic intrusion and 287Ma sulfide‐bearing mafic intrusion. The dioritic intrusion consists of biotite‐hornblende gabbro, diorite and quartz diorite. This intrusion was formed from a mixture of an evolved mantle‐derived magma and a crust‐derived adakitic magma combined with fractional crystallization of clinopyroxene, amphibole and plagioclase. The mafic intrusion is dominantly made up of norite in which sulfide ores, including disseminated, massive Ni‐Cu and massive Cu‐rich ores, are hosted. This intrusion was formed from two different pulses of basaltic magmas that had different magma evolution histories. The early magma pulse reached sulfide‐saturation due to minor crustal contamination and a small amount of sulfide (<0.03%) was removed before the emplacement. The evolved magmas then entered a shallow magma chamber and assimilated crustal materials to attain sulfide‐saturation again. Sulfide liquids segregated from the magma to form massive Ni‐Cu and massive Cu‐rich ores through further fractionation and residual silicate melts formed norites. A second pulse of magma underwent removal of <0.02% sulfides with stronger crustal contamination, and re‐attained S‐saturation during the emplacement and became a phenocryst‐laden magma. This magma then intruded the earlier formed massive sulfide ores and norites, forming the disseminated sulfide ores. The Permian Huangshandong mafic‐ultramafic intrusion hosts the largest magmatic sulfide deposit in east Tianshan. It consists of a layered unit of lherzolite, gabbro and diorite and a massive unit of olivine gabbronorite and gabbronorite. Both units formed from siliceous high magnesium basaltic (SHMB) magmas derived from a hydrous, depleted mantle source. The two units of the Huangshandong intrusion formed from magmas that have undergone different processes through the evolution of the magma plumbing system. The early magma pulse gained sulfur‐saturation before the emplacement and small amounts of sulfide (<0.03%) were removed to result in a PGE‐depleted, high‐Mg magma. This magma achieved sulfide‐saturation again in a staging magma chamber through crustal contamination and fractional crystallization of olivine and Cr‐spinel (an AFC process) to form the layered unit. A second magma pulse underwent fractionation of more olivine +/‐ Cr‐spinel but less sulfide (<0.003%) removal before the emplacement and became evolved, PEG‐undepleted and low‐Mg before the injection into the magma chamber. Mixing of the two magmas triggered sulfide‐saturation to form sulfide ores with variable PGE, Ni and Cu compositions. The study suggests that SHMB‐like magmatism, produced by melting of depleted and hydrous mantle source, may be an important feature of orogenic belts. Mafic‐ultramafic intrusions formed from SHMB‐like magmas may host economic sulfide deposits, particularly sulfide Ni‐Cu sulfide deposits.
published_or_final_version
Earth Sciences
Doctoral
Doctor of Philosophy

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47

Liu, Pingping, and 刘平平. "Petrogenesis of the Baima Fe-Ti-(V) oxide-bearing layered intrusion in the Emeishan large igneous province, SW China." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/207172.

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48

Richardson, Paul Douglas. "Pluton zonation unveiled by gamma ray spectrometry and magnetic susceptibility : the Sheeprock granite, western, Utah /." Diss., CLICK HERE for online access, 2004. http://contentdm.lib.byu.edu/ETD/image/etd614.pdf.

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49

Skidmore, Chloe Noelle. "Exploring Connections Between a Very Large Volume Ignimbrite and an Intracaldera Pluton: Intrusions Related to the Oligocene Wah Wah Springs Tuff, Western US." BYU ScholarsArchive, 2013. https://scholarsarchive.byu.edu/etd/4041.

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The Wah Wah Springs Tuff and the Wah Wah Springs Intrusive Granodiorite Porphyry(Wah Wah Springs Intrusion) both originated from the Indian Peak caldera complex, which wasa major focus of explosive silicic activity in the middle Cenozoic Great Basin ignimbrite flareup. This caldera formed 30.0 Ma when an estimated 5,900 km3 of crystal-rich dacitic magma erupted to create the Wah Wah Springs Tuff. The Wah Wah Springs Intrusion later intruded the tuff, causing resurgence of the caldera. Field, modal, and geochemical evidence suggest the tuff and intrusion are cogenetic. The mineral assemblages of the two rocks are similar: both include similar proportions of plagioclase, quartz, hornblende, biotite, clinopyroxene, and Fe-Ti oxides, with trace amounts of titanite, apatite, and zircon. Whole rock geochemistry also matches, and both rocks have distinctively high Cr concentrations. Plagioclase, hornblende, and clinopyroxene have similar compositions but biotite and Fe-Ti oxides have been hydrothermally altered in the intrusion. Both hornblende and quartz provide clues to the magmatic evolution of the Wah Wah Springs Intrusion. Hornblende grains are either euhedral, have reaction rims, or are completely replaced by anhydrous minerals. Deterioration of hornblende was caused by decompression as the magma ascended and then stalled and solidified at shallow depths. Two stages of quartz growth are shown in cathodoluminescence (CL) imagery. Quartz first grew then was resorbed during eruption, then grew again at lower pressures indicated by CL-bright quartz rims and groundmass grains. The geochemical and mineralogical similarities, together with the distinctive hornblende and quartz characteristics suggest that after the Wah Wah Springs Tuff erupted, the unerupted mush rose to a shallow level where it crystallized at low pressure to form the Wah Wah Springs Intrusion. This indicates that the both rocks formed in the same chamber, and that tuffs and associated intrusions can be intimately related.

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彭君能 and Kwan-Nang Pang. "Origin of the permian panzhihua layered gabbroic intrusion and the hosted Fe-Ti-V oxide deposit, Sichuan Province, SW China." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B39634000.

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