1 10 3 https://theses.otagogeology.org.nz/files/original/26d5e1c934bf4eb18609d5dc45d12860.pdf 7db1ecc06f212fab11cbf6cfe7c3f9ff Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Geology theses OU Geology thesis Thesis or dissertation completed by University of Otago Geology students Author last name Last name of the Author Brown Project type Is it an MSc, PhD, BSc(Hons) or PGDipSci? BSc(Hons) Advisers Who supervised/advised this student Palin, J.M. Abstract The Abstract for this thesis The New Zealand micro-continent has been described as an amalgamation of various tectonostratigraphic terranes which were accreted on to the Gondwana margin. The origin of the accreted terranes is important in the understanding of Phanerozic Pacific tectonics. This study aims to help in the understanding of the provenance of the Torlesse terrane, which has been subject to extensive geological research for decades. A conglomerate horizo11; located on the southeast side of Lake Hawea was examined with the aim of using the conglomerate clasts to provide provenance information on the Torlesse terrane, in particular the Rakaia terrane. Conglomerate clasts are coarsegrained hand specimen size samples of the source rock, which have thought to have travelled a shorter distance than the fine-grained detrital material which make up the Otago Schist and therefore are able to be used to trace proximal sources. The size of the clasts also allowed for much more extensive geochronological, geochemical, petrographical and geothermometry analysis than that of the fine-grained lithologies within the schist and therefore provide a more confident indicator of provenance. An additional goal of the studywas to understand the effect of metamorphism and deformation on the clasts. Based on geochemical and mineralogical observations, the majority of the clasts can be classified as fractionated I-type tonalite. Petrographic observations show that the clasts have been subject to low grade metamorphism, with the presence of recrystallised quartz and microfractured feldspar, pressure shadows and growth of stilpnomelane. Petrographic and geochemical observations indicate that the clasts have been subject to metasomatic additions ofNa20, Si02 and C02 and the removal ofK20, Rb and Ba during progressive metamorphism and deformation. Titanium (Ti) concentration in quartz grains for the three localities was determined by LA-ICP-MS. These data were combined with the revised calibration of Thomas et al. (2010) to estimate crystallization temperatures. Results show that at low metamorphic grades the original igneous Ti-in-quartz temperature was preserved, but with increasing metamorphic grade and textural zone the temperatures re-equilibrate. 111 U-Pb zircon ages for the five selected clasts and a schist sample were determined by LA-ICP-MS. Four igneous clasts yield crystallisation ages, 253±3 Ma, 298±3 Ma, 332±7 Ma and 339±6 Ma. A quartzite sample has detrital zircons that range in age from 440 to 2650 Ma. Detrital zircons within a schist sample showed a prominent Permian to Triassic age peak and correlate well with the ages of the clasts. The crystallisation ages of the clasts and the detrital ages of the schist and quartzite broadly correlate best with crystallisation ages of igneous complexes located within Western Antarctica. Department The department where the student is studying primarily. Geology Named locality Named locality describing the field area location. Hawea Thesis description Number of pages, maps, CDs, etc. vii, 137 : ill. (some col.), maps ; 30 cm Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Identifier An unambiguous reference to the resource within a given context 2010Brown Creator An entity primarily responsible for making the resource Brown, Kirstin Date A point or period of time associated with an event in the lifecycle of the resource 2010 Title A name given to the resource Provenance and metamorphism of conglomerates within the Otago schist, Hawea Subject The topic of the resource Geochemistry Hawea metamorphism Otago Schist provenance https://theses.otagogeology.org.nz/files/original/7c74b5668de132bb6b988976e5ff58c3.pdf 8e6f997894c7f3f8906d1d0553acba74 Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Geology theses OU Geology thesis Thesis or dissertation completed by University of Otago Geology students Location WKT (WGS84) The location stored in WKT (WGS84) format POLYGON ((170.87805011965915 -45.352666839861563,170.877434875500171 -45.40296724934916,170.850795918331045 -45.403361996964378,170.824853421067445 -45.38560393584121,170.827818367106602 -45.35231756677905,170.87805011965915 -45.352666839861563)) Author last name Last name of the Author Brown Project type Is it an MSc, PhD, BSc(Hons) or PGDipSci? BSc(Hons) Advisers Who supervised/advised this student Reay, A. Abstract The Abstract for this thesis The Moeraki Peninsula is located on· the east coast of the South Island of New Zealand, approximately 70 kilometres north of Dunedin. The regional schist basement, and the overlying fault derived breccias of the Shag Point Group both outcrop to the west (Mutch, 1963), and are not exposed on t~e Peninsula. These units are overlain by the marine sediments of the Moeraki, Kurinui, Hampden, and Iviokihi Formations, which collectively represent a marine transgressive sequence formed during a period of regional subsidence in the Eocene. The latter formations comprise fossiliferous mudstones and greensands, and are overlain by late Eocene or younger hyaloclastic volcanic agglomerates, breccias and tuffs, erupted in a submarine environment. Voluminous basaltic magmas, similar in age to the volcanics, have intruded the Tertiary sedimentary sequence to form numerous dykes and sills. The largest of these structtires is the Moeraki Dolerite, an elongated sill-like body which outcrops along the southeast coast of the peninsula, and has an estimated minimum volume of 0.06 cubic kilometres. The mineralogy of the Moeraki Dolerite is plagioclase feldspar (Anoo-An2o), diopside, augite, ilmenite, magnetite, and an unidentified amphibole. The minerals occur as both phenocrysts displaying a doleritic texture, and groundmass, where the feldspars display prominent chill textures, indicating quenching of the body after emplacement. The main body of the sill is basaltic in composition, ranging from ~48-53% silica, and has been intruded subsequent to emplacement and solidification, by a more differentiated liquid (Si02 ~52-62%) which has formed thin, laterally continuous veins, occurring throughout the main sill, spaced approximately lm apart, and running parallel to the upper and lower contacts of the latter. The major and trace element chemistry of these two rock-types suggest that the se~ond, more differentiated liquid was derived from the same source as the more basic main sill rocks, chemically differentiated by the fractional crystallization of olivine, clinopyroxene and plagioclase. Some crusta! assimilation of the regional schist basement is indicated by the dramatic silica enrichment seen in the differentiated veins, which can not be accounted for by fractional crystallization alone. The textures along the contact between the main sill rocks and the differentiated veins indicate that the latter were injected after the solidification of the former, but while it was still hot enough to prevent quenching of the second liquid. This short time frame suggests that the source magma chamber was probably already differentiated and zoned prior to the emplacement of the Moeraki Dolerite. Spatial chemical variation within the main sill rocks indicate that the outer margins of the sill are more differentiated than the central portions. Two petrogenetic models have been proposed, both involving multiple pulses of injection from a parent magma chamber at depth. One proposes that in-situ fractionation is responsible for the variation within the main sill rocks, while the second s~ggests that the variation is entirely the result of the tapping of a zoned magma chamber at depth. Schist xenoliths occur in the main sill rocks, and within a vein-like structure which is parallel to the upper contact of the Moeraki Dolerite, consisting of -90% xenoliths in a fine grained igneous groundmass. The layer may represent the injection of a liquid tapped from near the top of the parent magma chamber, where quartz xenoliths had been concentrated through floatation. Recent lithologies in the study area include extensive loess cover, raised beach deposits which represent sea-level fluctuations, and a mafic heavy mineral beach sand which occurs on the south coast of the peninsula, and is derived predominantly from the local dolerites through erosional processes. Department The department where the student is studying primarily. Geology Named locality Named locality describing the field area location. Moeraki Thesis description Number of pages, maps, CDs, etc. 149 p. : col. ill., maps ; 30 cm. Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Identifier An unambiguous reference to the resource within a given context 1993Brown Creator An entity primarily responsible for making the resource Brown, Justin. Date A point or period of time associated with an event in the lifecycle of the resource 1993 Title A name given to the resource Aspects of the geology of Moeraki Peninsula and the geochemistry of the Moeraki dolerite Subject The topic of the resource Geochemistry Hampden Formation Kurinui Formation loess marine terraces Moeraki Formation Moeraki Peninsula Mokihi Formation Otago Region https://theses.otagogeology.org.nz/files/original/ac43a0c6363695e26fc692867aa9acc0.pdf a0c130ae32b5d4cf8cfe4737e79bd7a7 Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Geology theses OU Geology thesis Thesis or dissertation completed by University of Otago Geology students Location WKT (WGS84) The location stored in WKT (WGS84) format POLYGON ((170.36594673500008 -45.616639051999982,170.352368813000112 -45.616360025999938,170.208429513000056 -45.613312699999938,170.20884602700005 -45.602641006999932,170.208853985000019 -45.602407127999982,170.210501595000096 -45.560282209999968,170.211186941000051 -45.542747603999942,170.211281533000033 -45.540359609999939,170.249009269000112 -45.541326722999941,170.257128221000016 -45.541532823999944,170.278577376000044 -45.542076501999929,170.400311653000017 -45.545084479999957,170.397636511000087 -45.617282555999964,170.36594673500008 -45.616639051999982)) Author last name Last name of the Author Brown Project type Is it an MSc, PhD, BSc(Hons) or PGDipSci? MSc Advisers Who supervised/advised this student Coombs, D.S. Means.W.D. Abstract The Abstract for this thesis The area mapped lies south-east of Middlemarch, Eastern Otago. It is underlain mostly by schist but also includes several small Tertiary outliers of basanitic volcanics resting on a thin formation of quartz sands and conglomerates. The lithology, mineralogy and structure of the schist are reported. From these studies the following conclusions are made: (1) bedding in a wide range of thicknesses is recognizable in the schist, (2) the area lies within a biotite and possibly garnet zone of metamorphism, (3) retrogressive metamorphism occurred and appears to have been accompanied by a deformational phase, (4) there were at least two phases of deformation during the metamorphic period - the first may have produced large-scale recumbent folds. A section on the post-metamorphic geology includes a study of the sedimentary and volcanic formations, post-metamorphic structures, and geomorphology. A post-metamorphic history is given and compared with the regional geology. It appears that the area was stable throughout the lower and middle Tertiary. Department The department where the student is studying primarily. Geology Named locality Named locality describing the field area location. Mt Stoker Thesis description Number of pages, maps, CDs, etc. xii., 121 p., Map folded in pocket., photoes and illus., 27cm. Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Identifier An unambiguous reference to the resource within a given context 1963Brown Creator An entity primarily responsible for making the resource Brown, Edwin H. Date A point or period of time associated with an event in the lifecycle of the resource 1963 Title A name given to the resource The geology of the Mt. Stoker area Subject The topic of the resource Map Igneous petrology Metamorphic geology Sedimentology Structural geology biotite-?garnet zone retrograde metamorphism