1 10 16 https://theses.otagogeology.org.nz/files/original/cac3974fa8baace61ecbf7727109b12f.pdf 34a64be4e76b2fd7163e5560fb75afad 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 MULTIPOLYGON (((170.900343773359992 -45.188078523398133,170.898767846116527 -45.189716713569119,170.892786162634394 -45.187522475582348,170.894871430131872 -45.185774676190533,170.900343773359992 -45.188078523398133)),((170.932193375261505 -44.521407093012698,170.929875595024129 -44.521422255808382,170.930140528097809 -44.518454401465043,170.932615869142694 -44.518499253012124,170.932193375261505 -44.521407093012698)),((170.996582916551688 -44.301173131306996,170.955562850685908 -44.313308929027819,170.95123103847996 -44.30622816149225,170.991048863702247 -44.29421567998218,170.996582916551688 -44.301173131306996))) Author last name Last name of the Author Tinto Project type Is it an MSc, PhD, BSc(Hons) or PGDipSci? PhD Advisers Who supervised/advised this student Wilson, G.S. Gorman, A.R. Abstract The Abstract for this thesis The Marshall Paraconformity is a widely recognised surface in the mid-Oligocene sedimentary record of New Zealand and the south Pacific. Its type section has been defined at Squire's Farm in South Canterbury, South Island, New Zealand where it forms the burrowed top of the Early Oligocene (Whaingaroan) Amuri Limestone and is overlain by a thin deposit of the Late Oligocene (Duntroonian) Kokoamu Greensand. In the stratigraphic framework of the Canterbury Basin it marks the turning point between the extensional tectonics of rifting from Gondwana and the transpressional tectonic regime associated with the present day Australian-Pacific plate boundary. The development of the unconformity has been attributed to the initiation of the Antarctic Circumpolar Current and the eustatic sea level changes associated with the development of continental ice sheets on Antarctica in the early Oligocene. Controversy has surrounded the Marshall Paraconformity, particularly regarding correlation between exposures and the regional significance of the surface. A new record for the Marshall Paraconformity has been recovered in a 273 m drillcore (TNW- 1) from near the settlement of Cave in South Canterbury, 30 km to the north of the type section. Rock and environmental magnetic studies reveal weakly magnetised sediments with remanence carried by fine-grained magnetite with a minor contribution from iron sulphides (likely greigite) and iron oxyhydroxides (goethite and hematite). The clearest paleomagnetic signal is held by the Kokoamu Greensand, with 0.2-1 [mu]m grains of magnetite, a very small component of goethite and no evidence of iron sulphides or hematite. The Kokoamu Greensand has a reversed magnetic polarity, and is correlated with Chron C7r (25.183-25.496 Ma) using biostratigraphic constraints. This is the most precise age constraint available for the resumption of deposition on the Marshall Paraconformity. Glaucony deposition at TNW-1 predates that at Squire's Farm and accumulation rates were relatively high (~5 cm/kyr) indicating that glaucony did not develop in situ. A 3 km seismic profile across the drill site was correlated with the core by a synthetic seismogram. The Marshall Paraconformity was identified as a high-amplitude reflection showing slight angular discordance between discontinuous reflections below the unconformity and continuous, parallel reflections above. Erosion on the Marshall Paraconformity was also inferred from the local absence of the Amuri Limestone at TNW-1. Reflections underlying the Marshall Paraconformity in the seismic profile show evidence of further angular discordance, indicating tectonic activity in the Bortonian, possibly related to the development of the Fairlie Basin to the north. The difference in timing of the unconformity at TNW-1 from Squire's Farm to the south is attributed to these local tectonic variations. The TNW-1 record has been compared with other records from the Canterbury Basin, in a north-south transect including Otaio Gorge (near the Marshall Paraconformity type section) and the Kakanui River Mouth, a site of Eocene volcanic activity. Throughout these different local tectonic environments, the Marshall Paraconformity is a recognisable surface, indicating a regional cause of the unconformity. Comparing the timing of the initiation of the hiatus and resumption of deposition, the shallow-water Marshall Paraconformity correlates well with the proposed eastward shifting of the Proto-Ross Sea Gyre after the opening of the Tasman Gateway. Shallow currents were redirected across the New Zealand continent in the early Oligocene and may have been responsible for non-deposition and erosion on the unconformity. These shallow currents were diverted by the development of the Antarctic Circumpolar Current, allowing the reworking and deposition of glaucony, possibly from the Campbell Plateau. Age estimates for the deep-water occurrences of the Marshall Paraconformity (ODP Sites 1123 and 1124) indicate an earlier initiation of the hiatus (~33 Ma). These sites were likely beneath the influence of shallow-water currents, and it is suggested that the development of the unconformity here was due to corrosive bottom waters associated with the development of sea ice around Antarctica, rather than the initiation of circumpolar flow. A record of the Marshall Paraconformity from intermediate depths (IODP Site 1352) most closely resembles the shallow-water Marshall Paraconformity. The resumption of deposition on the shallow water Marshall Paraconformity indicates the initiation of the Antarctic Circumpolar Current while the deep water Marshall Paraconformity formed earlier in response to increased glaciation on Antarctica. OURArchive handle The handle from the Otago University Research Archive (OURArchive) <a href="http://hdl.handle.net/10523/3942">http://hdl.handle.net/10523/3942</a> OURArchvive access level Abstract Only Department The department where the student is studying primarily. Geology Named locality Named locality describing the field area location. South Canterbury New Zealand Thesis description Number of pages, maps, CDs, etc. xxviii, 288 p : col. ill ; 30 cm + 1 CD-ROM (4 3/4 in.) 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 2010Tinto Creator An entity primarily responsible for making the resource Tinto, Kirsty 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 A geophysical investigation of the Marshall Paraconformity in South Canterbury, New Zealand Subject The topic of the resource Sedimentology Amuri Limestone Canterbury Basin Kokoamu Greensand Marshall paraconformity Oligocene https://theses.otagogeology.org.nz/files/original/9412452d7853be3c9b7f7db9d5ecea16.pdf 849601d711c08df160664c194fdb1528 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 ((170.49208587144679 -45.875505277967079,170.708448802772551 -45.754309756642918,170.757785817279682 -45.77958032861909,170.555098806497938 -45.900209980862101,170.49208587144679 -45.875505277967079)) Author last name Last name of the Author Shears Project type Is it an MSc, PhD, BSc(Hons) or PGDipSci? MSc Advisers Who supervised/advised this student Smith, A. Gorman, A.R. Abstract The Abstract for this thesis Urban tidal inlets often lend themselves to economically important port development. In many cases, such inlets are artificially deepened and maintained for continuous human use. A range of ecological, hydrological, sedimentological and financial impacts can result from such manipulation. A good understanding of a sedimentary system provided by a comprehensive sediment budget allows informed decisions and planning and encourages sustainable coastal management. The aim of this research was to develop, for the first time, a sediment budget for Otago Harbour, on the southeast coast of New Zealand. Otago Harbour is a highly modified tidal inlet that occupies two river-incised (and/or fault-incised) volcanic valleys. Previous research has investigated many sediment inputs and outputs for Otago Harbour but there is a lack of research relating to sediment storage, thickness and sedimentation rate. This thesis assesses sediment thickness throughout Otago Harbour using three complementary methods: (1) a geometric bedrock model, (2) land-based gravity anomaly profiling, and (3) marine seismic reflection surveying. The geometric model, developed from topography and bore records using a maximum bedrock depth of 120 m (sea level at the last glacial maximum), estimated a maximum sediment volume in Otago Harbour of almost 5 billion m3 . Land gravity surveys (at Aramoana, Upper Harbour Basin and St Kilda/St Clair) and marine seismic reflection surveys refined this estimate to 1.62 billion m3 . Gravity modelling found the maximum sediment thickness to be -100 m at the modem harbour entrance and > 70 m at the St Kilda paleo-river mouth, whereas the seismic survey found the greatest basement depth ( -76 m) just inside the entrance at Harington Point. Taken together, these findings suggest that the sediment package accumulated at a rate of -90,000 m3/y since the last glacial maximum (equivalent to -2 mm/y). However, this rate of storage no longer occurs because of the current dredging regime. In the present sediment budget, sediment entering the harbour on the flood tide (619,000 m3/y) is the dominant sediment input to the system (626,000 m3/y), though most of it exits the harbour on the ebb tide (516,000 m3/y). The difference is more than compensated for by seafloor dredging, which removes more sediment than the net 111 amount entering the harbour (-28,000 m3/y), thus removing stored sediment. As a result, the harbour's sedimentary system is in deficit, and the deficit is likely to increase in the future if dredging continues at the same long-term rate (244,000 m3/y). Otago Harbour can no longer be deemed an "infilling harbour"; human intervention has overturned that natural balance. Instead, the system's deficit may explain recent erosion at Te Rauone Beach. Furthermore, the lack of carbonate sediment accumulation, due also to changes in early seafloor processes, means that Otago Harbour plays a reduced role in preservation of carbonate information and sequestering of atmospheric C02. Human activities in other urban tidal inlets may have caused similar deficits. As modelled for Otago Harbour, the next century promises to bring a great deal of change (climate, ocean chemistry, urban development) with unexpected consequences for urban tidal inlets. Department The department where the student is studying primarily. Geology Named locality Named locality describing the field area location. Otago Harbour Thesis description Number of pages, maps, CDs, etc. xvi. 170 p. ill (some col) maps folded in pocket. 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 2010Shears Creator An entity primarily responsible for making the resource Shears, Amy 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 Characterisation of the sediment budget of Otago Harbour: a geophysical and sedimentological study Subject The topic of the resource Geophysics sedimentology geophysics modified tidal inlet sediment budget sedimentology. https://theses.otagogeology.org.nz/files/original/9b2e4d651d320427e3c84a79c0d427df.pdf 24e712f6349f496fb1f8727dc4a5563d 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 Schipper Project type Is it an MSc, PhD, BSc(Hons) or PGDipSci? PhD Advisers Who supervised/advised this student White. J.D.L. Abstract The Abstract for this thesis Even though the vast majority of volcanism on Earth occurs under water, very little is known about submarine volcanoes and their eruptions. The hydrostatic pressure at submarine vents was long thought to preclude submarine explosive eruptions, until recent exploration with submersibles revealed that widespread volcaniclastic deposits bearing striking similarity to the products of subaerial explosive eruptions are found to great depths in all the world's oceans. This has inspired the current investigation into the relative roles of magmatic degassing and magma-water interaction that permit submarine basalt explosivity in the deep sea. Lo'ihi Seamount is the youngest and southernmost active volcano in the HawaiianEmperor Volcanic Chain. Its~ 1 km deep summit plateau is home to many different volcaniclastic and pyroclastic deposits. A sampling-focused submersible dive series to Lo 'ihi in 2006 provided the material for this study, which is divided into three parts, covering: Poseidic scoria cones, primary pyroclastic deposit L8, and limu o Pele. The "Poseidic" name is introduced for an end-member style of submarine basalt explosivity identified by measurable features ofpyroclasts from two scoria cones on Lo'ihi's summit plateau. Vesicle textures in lapilli, dissolved volatiles in matrix glasses and olivine hosted glass inclusions, and fine ash morphology, are used to constrain this uniquely submarine, cone-forming style of eruption. The Poseidic eruption style involves cooperative processes of strongly volatile-coupled degassing and hydromagmatic fragmentation, that challenge traditional assumptions about depth limitations to these processes. A bedded, primary pyroclastic deposit ("L8"), exposed in a fault scarp on Lo'ihi's summit plateau allowed a series of samples to be collected upward through a volcaniclastic sequence. The bedding characteristics, clast vesicularities, microtextures, and geochemistry through the stratigraphy of this deposit indicate that the magma experienced variable ascent rates, and complex cooling regimes in the conduit. Deep-sea limu o Pele, shards of basaltic glass commonly described as "bubble walls," were found concentrated in ash lenses interbedded with thin lava sheets, and separated from an overlying volcaniclastic sequence by a discontinuity. Different theories have been presented about how these enigmatic particles form, either by hydrovolcanic volcanism, when submarine lava flows entrap and vaporise seawater, or by Strombolian-like explosive eruptions. The geometry and geochemistry of the Lo'ihi deposit provides compelling evidence for a hydrovolcanic, sheet-flow related origin. Theoretical considerations are presented to demonstrate that this process is viable even below the critical depth of seawater, where limu formation is driven by supercritical water, rather than water vapour. Submarine explosive eruptions are usually described by analogy to classical subaerial eruption styles, and many key eruption style-determining processes have previously only been treated theoretically. The robust samples collected for this study, and the detailed treatment of them, shows: (1) that submarine explosive eruptions are different from subaerial ones in almost all ways; (2) that many classical theories about what is and what is not possible at submarine volcanoes need constant reevaluation as new data become available; and (3) that the textures and chemistry of submarine pyroclasts can be used to rigorously determine eruption styles. Department The department where the student is studying primarily. Geology Named locality Named locality describing the field area location. Lo'ihi seamount Hawai'i Thesis description Number of pages, maps, CDs, etc. ix, 218, 47 p. : ill. (some col.) ; 30 cm. + 1 CD-ROM. 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 2010Schipper Creator An entity primarily responsible for making the resource Schipper, C. Ian. (Christopher Ian) 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 Explosive submarine volcanism at Lo`ihi Seamount, Hawai`i Subject The topic of the resource Volcanology Lo'ihi seamount. Hawahi'I Submarine explosive eruptions. https://theses.otagogeology.org.nz/files/original/8731fddad845f7d965aeb7c008c9d8e6.pdf 61db16121097959ba807d092b15b09c5 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 ((170.077623295189767 -43.401979878992819,170.073324524716924 -43.516515094733009,169.909510835274403 -43.511307434252778,169.910024478114963 -43.396974725428358,170.077623295189767 -43.401979878992819)) Author last name Last name of the Author Reid-Lindroos Project type Is it an MSc, PhD, BSc(Hons) or PGDipSci? BSc(Hons) Advisers Who supervised/advised this student Toy, V.G. Abstract The Abstract for this thesis Vein characteristics and textures, particulary crystallographic preferred orientations (CPO) were investigated using computer integrated polarisation microscopy (CIP) in ~20 quartz veins over the course of this study. Grain size and grain shape preferred orientation (GSPO) were also analysed. Samples were taken from a fault perpendicular section within the hanging-wall mylonites of the Alpine Fault in Cataclasite Creek on the West Coast of the South Island, New Zealand. The quartz veins occur within two different mylonitic lithologies; quartzofeldspathic mylonite and metabasic mylonite (~30-40% total mylonite volume). The proportion of metabasic to quartzofeldspathic mylonite may have implications for localised fault behaviour and amount of dip-slip movement on the Alpine Fault. The quartz veins mostly lie at low angle to or parallel to the mylonitic foliation. These veins may initially have formed in three different scenarios, each of which should produce a different final CPO; (1) veins inherited from the Alpine Schists which were already deformed before incorporation into the mylonite zone, (2) veins opened parallel to foliation at depth within the mylonite zone, and (3) veins opened at high angle to foliation at depth within the mylonite zone. In all three scenarios we expect an original CPO within the veins. The samples display CPOs ranging from crossed girdles, representative of low temperature basal <a> glide to concentrated Y-maxima fabrics characteristic of prism <a> glide, and possible constrictional fabrics. CPOs within quartzofeldspathic and metabasic mylonites differ significantly. The metabasic mylonites have more grains favourably oriented for prism <a> glide, and some indicate antithetic sense of shear to adjacent quartzofeldspathic mylonites, and to the overall sense of shear within the Alpine Fault zone. Several veins within both lithologies have a domainal CPO, which may indicate that they have not undergone enough recrystallisation to completely change the initial CPO, or that different starting orientations responded differently to the same deformation. In either case, preservation of these domains suggests these veins were generated within the mylonite zone rather than inherited from the Alpine Schist. The large variation in CPO between veins hosted in quartzofeldspathic and metabasic lithologies suggests the rheologically distinct metabasic pods may either shield quartz veins from deformation, or focus deformation into them. GSPOs appear to be correlated with dominant quartz slip system; samples displaying prism <a> and rhomb <a> slip have GSPOs at higher angle to the foliation than those exhibiting basal <a> slip. Department The department where the student is studying primarily. Geology Named locality Named locality describing the field area location. Alpine Fault Thesis description Number of pages, maps, CDs, etc. 95 leaves : ill., 1 folded map in pocket ; 30 cm. + 1 CD-ROM (4 3/4 in.) 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 2010Reid_Lindroos Creator An entity primarily responsible for making the resource Reid Lindroos, Zoe. 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 Variation in characteristic and texture of quartz veins normal to the Alpine Fault Subject The topic of the resource Structural geology Alpine Fault texture of quartz veins https://theses.otagogeology.org.nz/files/original/54a65a52b664092f4c864fbecf6bfeeb.pdf f67735fe7d46f366e5d21931f4846aa3 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 ((163.51796987207328 -79.117033434886579,163.316711702873562 -79.250702116712105,162.587428940190193 -79.20637268614216,161.374780120602281 -79.12804342787328,159.852029996568433 -79.021251358902745,160.054225218050334 -78.909021516065479,160.174069596234887 -78.841362589513821,160.195221475082519 -78.829331620800204,160.240202151822842 -78.803656908542351,160.267247414585256 -78.788160294046023,160.444048222510474 -78.68574345949186,160.550735279900863 -78.622993460720011,161.132484113033513 -78.267675565089718,161.369320508132802 -78.116330973777607,161.37788099027614 -78.110784801515251,161.432520491913806 -78.075258242852868,161.49739750788649 -78.080055046342423,161.839747257784694 -78.105059450528444,161.994023113846879 -78.116159074052405,162.007047389816393 -78.117091362381188,162.392982814988756 -78.144381942682159,162.521412492366551 -78.153320528971605,162.544050376938856 -78.154888735378563,162.549828014784254 -78.155288619674636,162.567466868901477 -78.156508558872986,162.627000327708657 -78.160616138052802,162.752444164408416 -78.169221494525672,163.022634293744574 -78.187527903959761,163.05659484093735 -78.189806869804784,163.428357826602706 -78.214435253501506,163.441323801388563 -78.215283696950735,163.604408787668177 -78.225895082769853,163.620311001580717 -78.226923820518422,163.94341198329613 -78.247597118927885,164.086523095636579 -78.256615260407415,164.262323738480376 -78.267577413480822,164.372748812889512 -78.274397914040435,164.470315588489228 -78.280382530086953,164.556468589723067 -78.285634608412707,164.632111397920994 -78.29022093665516,164.65660632974587 -78.291701089635879,164.656606843479665 -78.291701120721555,164.630777329187936 -78.311839110512864,164.612216200999711 -78.326266762639165,164.557982328973793 -78.368215768190026,164.553163972372346 -78.371927828837343,164.477628770719463 -78.429805959042625,164.45392014501607 -78.44785151447914,164.364955183519925 -78.515057268720028,164.359704446412479 -78.518998847651645,164.265856514741841 -78.58898501930031,164.260074502234716 -78.593268427651708,164.152964126278192 -78.672027861183167,164.125787870668546 -78.691834506770746,163.949080296831397 -78.81891635445821,163.678871259895828 -79.007691262474765,163.51796987207328 -79.117033434886579)) Author last name Last name of the Author Read Project type Is it an MSc, PhD, BSc(Hons) or PGDipSci? PhD Advisers Who supervised/advised this student Cooper, Alan Reay, A. Palin, J.M. Abstract The Abstract for this thesis The Koettlitz Glacier Alkaline Province, in southern Victoria Land, Antarctica, is characterised by Late Neoproterozoic, extension-related plutonism. Stretching 100 kilometres along the Hillary Coast from the Radian Glacier, in the north, to the Mulock Glacier, in the south, the Koettlitz Glacier Alkaline Province is exposed over at least 2000 km². The oldest intrusions dated during this study are mafic members of the Glee Suite, a suite ranging from 46 wt% SiO₂ alkaline gabbros to 68 wt% SiO₂ quartz monzonites that crop out in the north of the studied area, between the Kempe and Panorama Glaciers. Enriched in Ti, Fe, Mn, K, P & Ba, the Glee Suite comprises borderline subalkaline/alkaline, metaluminous, calc-alkalic/alkali-calcic, transitional basalts and derivatives. Initial epsilon Nd ( -2.58) and initial ⁸⁷Sr/⁸⁶Sr (0.708) values are more primitive than most nearby intrusions, indicating lesser crustal input in the Glee Suite. Zircon ages of 553 ± 5 Ma & 550 ± 5 Ma date emplacement, while titanite ages of 538 ± 2 Ma & 534 ± 1 Ma date subsequent deformation then cooling. Geochemical characteristics of the Glee Suite imply emplacement into a failed intra-continental rift. The alkaline gabbroic components of the Glee Suite are geochemically equivalent to alkaline components of the nearby Panorama Pluton and Dromedary Mafic Complex. The Skelton Mafic Suite, which crops out on both sides of the Skelton Glacier in the vicinity of Cocks Bluff, ranges from magnesian, calcic, 48 wt% SiO₂ gabbros to ferroan, calc-alkalic, 59 wt% SiO₂ monzonites. This array is a result of fractional crystallisation from a gabbroic end member such as sampled at Breezy Bluff, one kilometre northeast of Cocks Bluff. Zircon and titanite from the Skelton Mafic Suite have been dated at 548 ± 2 Ma and 547 ± 4 Ma, respectively, indicating emplacement at this time. The subalkaline Skelton Mafic Suite is part of a broader mafic association within the Koettlitz Glacier Alkaline Province that contains both subalkaline and alkaline components. This association includes the Panorama Pluton (557 ± 5 Ma) and the Dromedary Mafic Complex. The outcrop characteristics and geochemical nature of these subalkaline-alkaline mafic intrusions indicate emplacement in a transitional compressional / extensional tectonic setting. The most characteristic suite in the Koettlitz Glacier Alkaline Province is the Hillary Suite that comprises high-silica, A₂ group, A-type granitoids and subordinate syenites. Members of the Hillary Suite are enriched in Si, Fe, Na, K, Ga, Nb, La, Nd, Rb, Y, Pb, Th & U and depleted in Al, Mg, Ca, Ba & Sr. Strong enrichment in REE, particularly the LREE (La(N)/Lu(N)=5-40), and large negative Eu anomalies (Eu/Eu*=0.04-0.53) are apparent in all samples. The Sm-Nd & Rb-Sr isotopic character of the Hillary Suite (initial epsilon Nd = -4.5 to -7.5 and initial ⁸⁷Sr/⁸⁶Sr 0.708-0.710) suggests derivation from crustal rather than mantle source rocks. New Hillary Suite emplacement ages of 550 ± 3 Ma, 548 ± 4 Ma, 546 ± 3 Ma, 546 ± 3 Ma and 542 ± 3 Ma are all Late Neoproterozoic. The geochemical nature, geographic spread and emplacement ages of the Hillary Suite indicate that the Koettlitz Glacier Alkaline Province was the site of broad crustal extension during the Late Neoproterozoic. OURArchive handle The handle from the Otago University Research Archive (OURArchive) <a href="http://hdl.handle.net/10523/5428">http://hdl.handle.net/10523/5428</a> OURArchvive access level Open Department The department where the student is studying primarily. Geology Named locality Named locality describing the field area location. southern Victoria Land, Antarctica Thesis description Number of pages, maps, CDs, etc. 630pp total 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 2010Read Creator An entity primarily responsible for making the resource Read, Stephen E 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 Koettlitz Glacier Alkaline Province : Late Neoproterozoic extensional magmatism in southern Victoria Land, Antarctica Subject The topic of the resource Plutonic Alkaline Province Antarctica https://theses.otagogeology.org.nz/files/original/25e5fe9e9eb57839b026807304d4b35b.pdf ece0f8554357046e4aaa2931cee5b469 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 Ortega Project type Is it an MSc, PhD, BSc(Hons) or PGDipSci? MSc Advisers Who supervised/advised this student Fordyce, R.E. Abstract The Abstract for this thesis Early Miocene (~23-16 Ma) rock units—the Mount Harris Formation (Otaian – Altonian) and Gee Greensand (basal Otaian)—at Awamoa Beach, North Otago, preserve fossils of extinct Cetacea. The Early Miocene is a significant time in cetacean history as the interval where some archaic whales declined and the bulk of modern cetaceans began to dominate the oceans. Awamoa Beach—historically important as the locality from which the first New Zealand fossil cetacean was described—became accessible as a fossil site in 1999. Thus far, it has produced a diverse assemblage of Early Miocene whale fossils which expands the patchy global record of Early Miocene cetacean localities. This project records four fossil cetacean skulls and some post-cranial material recovered from Awamoa Beach within the last decade. Fieldwork as part of this thesis was precluded by a thick layer of shingle that has overlain Awamoa Beach units since mid 2008, so that research concentrated on fossils already collected from Awamoa Beach (curated in the Geology Museum, University of Otago); some are documented here. I used physical and chemical preparation methods to remove matrix from some of the fossils. Subsequently, I have identified four odontocetes and discussed their phylogenetic relationships with previously documented odontocetes. Among the recovered cetacean fossils of Awamoa Beach, one partial skull and its associated post-cranial material, OU22466, most likely represents the short-jawed shark-toothed dolphin, Prosqualodon cf. davidis, hitherto known only from Australia. This is the first firm report of a Prosqualodon skull from New Zealand. Specimen OU22672 likely represents an early member of Delphinoidea. The interconnected sinus fossae of the basicranium and pronounced asymmetry of the skull suggest that it is a specialized odontocete that is phylogenetically related closely to delphinids. Poor preservation precludes firm taxonomic placement. The skull was found as float on Awamoa Beach so an experiment—one of the first of its kind from New Zealand—was designed and conducted to liberate foraminifera from the matrix of the skull to date the specimen. Although the experiment did not produce diagnostic foraminifera that could date the skull, it identified procedures for liberating foraminifera that could prove useful to future studies. Another important skull is OU22670, a new genus and species of the Pomatodelphininae which is the sister taxon of extant Platanista, the river dolphin of the Indian subcontinent. The results of a cladistic analysis suggest that OU22670 is the sister taxon of Prepomatodelphis from the late Early Miocene. Thus, OU22670 extends the global fossil record of Platanistidae to earlier in the Miocene and suggests that Platanistidae did not originate in the northern Atlantic Ocean as previously believed. Additionally, the highly derived characters of OU22670 indicate that it is more specialized than Prepomatodelphis. OU22465 is an enigmatic specimen that has a ‚rostral bulge‛, a feature not documented from any other odontocete taxon. This feature is somewhat similar to the large maxillary crests of Squalodelphinidae and Platanistidae. This incomplete skull is documented as Odontoceti: Platanistoidea incertae sedis. The findings of this project suggest that Awamoa Beach could be regarded as one of the globally few significant Early Miocene cetacean fossil localities. Department The department where the student is studying primarily. Geology Named locality Named locality describing the field area location. North Otago Thesis description Number of pages, maps, CDs, etc. xxvi, 211 leaves : col. ill ; 30 cm. + 1 CD-ROM (4 3/4 in.) 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 2010Ortega Creator An entity primarily responsible for making the resource Ortega, Megan Emily. 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 Early Miocene whales from Awamoa Beach, North Otago Subject The topic of the resource Paleontology fossils Miocene whales https://theses.otagogeology.org.nz/files/original/0491235e0f21741a399503f750070413.pdf ca90dcf66c915eeafa2dc20b59487954 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 Orchiston Project type Is it an MSc, PhD, BSc(Hons) or PGDipSci? PhD Advisers Who supervised/advised this student Higham, J.E.S Sibson, R. Abstract The Abstract for this thesis The islands of New Zealand lie astride two actively deforming tectonic plates, creating a diverse physical landscape with high scenic value, but one which is prone to a range of natural hazards. The Alpine Fault is a 450 km-long fault which defines the position of the plate boundary as it runs the length of the Southern Alps in the South Island. Paleoseismic evidence suggests it is overdue for a significant earthquake of magnitude ~ 7.8 - 8. Coincident with this area of high seismic potential is a burgeoning tourism industry, which, over the past two decades has shown remarkable growth, capitilising on the region’s international reputation for unique nature-based tourism experiences. Visitor activities occur, at times, in relatively remote and hazardous settings, such as National Parks, alpine or coastal areas. Many tourism destinations in the Southern Alps can only be accessed via alpine passes or road ends. This research project adopted three methodological approaches to satisfy two objectives. The first objective of the study investigated the physical outcomes of a large Alpine Fault earthquake on the tourism industry. Modelled isoseismal data for a number of earthquake magnitude scenarios were combined with map overlays illustrating tourist destinations, transport infrastructure, activity settings and travel flows, using ArcView GIS software. The second objective used a quantitative methodology involving a postal survey to gain insights into the total population of tourism operators around the Southern Alps, which generated a 51% response rate. It investigated operator perceptions of regional seismic risk, their perceived level of preparedness, and the factors that influence the resilience of tourism businesses. A third methodological tool involved semi-structured interviews with key tourism stakeholders and tourism business operators to add greater depth and support to the interpretation of the quantitative results. Results from objective one showed that a magnitude 8 earthquake is likely to produce severe damage to infrastructure, buildings and roads, and cause lengthy interruption to human activities throughout the Southern Alps. Widespread landsliding will cause an immediate drop in visitation due to road closures, with long-term repair work (> 6 months) required to restore access. Visitors in many small, remote, tourism-based communities will be left stranded for a period of days until emergency authorities begin evacuating those most in need, adding to the immediate burden on communities. Medium to long-term recovery outcomes may be hampered by on-going aggradation of sediment in fluvial systems, particularly on the western side of the Alps. Post-disaster recovery in terms of visitation is predicted to take approximately 12-18 months, depending on the timing of the earthquake. Objective 2 results suggested tourism operators understand the likelihood of an earthquake on the Alpine Fault, but lack awareness of the potential consequences for their business. Business owners consider themselves to be poorly prepared for a large earthquake, although they see the benefit in taking steps to become more prepared. Emergency managers should make efforts to convert tourism operator motivations into improved business preparedness, primarily by making business preparedness information more readily available to the tourism sector. Demographic variables were found to have only weak correlation with business preparedness. Business characteristics, such as business longevity, size and turnover, had varying degrees of influence on the uptake of key resilience ‘tools’, including continuity insurance, induction, staff training and disaster planning. Levels of continuity insurance and disaster planning were found to be inadequate and in need of significant improvement in light of the expected outcomes of a future Alpine Fault earthquake on business function. To date, there has been a significant gap in our understanding about earthquakes and their potential effects on the tourism industry in New Zealand. This doctoral research project built upon the crisis management and risk perception literature by providing critical insights into the seismic risk perceptions and preparedness of business managers in a sector of the New Zealand economy growing in prominence. In addition, it brought together the study of tourism with the science of earthquakes to develop a clear illustration of the physical outcomes of a future Alpine Fault earthquake around the Southern Alps. A magnitude 8 event will cause considerable disruption to tourism activities for a prolonged period. Improvements in business preparedness and resilience are urgently needed, which could be achieved using innovative business and community-driven initiatives, with improved communication and support from government agencies. OURArchive handle The handle from the Otago University Research Archive (OURArchive) <a href="http://hdl.handle.net/10523/395">http://hdl.handle.net/10523/395</a> OURArchvive access level Open Access Department The department where the student is studying primarily. Tourism Geology Named locality Named locality describing the field area location. Alpine Fault New Zealand.Tectonics Thesis description Number of pages, maps, CDs, etc. xxiv, 317 p. : col. ill ; 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 2010Orchiston Creator An entity primarily responsible for making the resource Orchiston, Caroline Hamilton 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 Tourism and Seismic Risk: perceptions, preparedness and resilience in the zone of the Alpine Fault, Southern Alps, New Zealand. Business preparedness Earthquake Perceptions resilience Seismic risk Tourism https://theses.otagogeology.org.nz/files/original/d923ce5e343310f0d33826b89af89aa6.pdf 8e74caab697e7d9aff1d98e847f59da9 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 Nelson Project type Is it an MSc, PhD, BSc(Hons) or PGDipSci? PhD Advisers Who supervised/advised this student Wilson, G.S. Abstract The Abstract for this thesis A high standing oceanic island in the mid-latitudes of the South Pacific, New Zealand is well situated to record far-field effects of global climate change. A 1.8 Ma paleomagnetic and environmental magnetic record from the Challenger Plateau, Tasman Sea, is presented here. Continuous sub-samples (u-channels) were collected from three long (up to ~40 m) giant piston cores (MD06-2987, -2988 and -2989), as well as shorter cores (TAN0712-14, -15, -17, -23, -27), within the global westerly system in front of New Zealand's Southern Alps. Magnetic grain size in the cores was determined from anhysteretic remanent magnetism (κARM) and volume magnetic susceptibility measured on u-channel samples using a pass-through cryogenic magnetometer with an in-line Bartington MS2C susceptibility bridge and solenoid in a shielded room (150 nT). Magnetic mineralogy was investigated using temperature-dependent susceptibility, hysteresis parameters and elemental analysis. Age control was achieved through radiocarbon ages, and correlation of the paleomagnetic inclination and relative paleointensity records (derived from NRM/saturationARM; RPIarm) to radiometrically dated geomagnetic excursions. An inclination anomaly and RPI minima in TAN0712-14 at 29.92 cal ka BP (2σ age range: 29.36 : 30.5 cal ka BP) is inferred to record the Mono Lake excursion and falls within the error range of the published radiometric age, supporting a relatively rapid lock-in of the paleomagnetic signal. MD06-2987, -2988 and -2989 make up a relative paleointensity (RPIarm) stack---West Coast South Island 1800-ka or WCSI-1800---and contain fifteen Brunhes and Matuyama excursions. Correlation with other stacks and the presence of coeval paleointensity minima support it as a South Pacific representation of Earth's geomagnetic field. Influxes of fine magnetic minerals in cores MD06-2988 and -2989 are inferred to be a clay content (ice cap glaciation) proxy and correlate with cold stadials (MIS 58, 52, 38, 36, 20 and 6). The magnetic grain-size record of MD06-2989 has spectral power at both obliquity and precession frequencies. Magnetic grain-size fining in MD06-2987 corresponds to Antarctic warm events (A6-A1) and implies circum-Antarctic waxing and waning in bottom water production on millennial timescales during the last interglacial. Higher frequency fining events correlate to millennial-scale warm Antarctic Isotopic Maxima events (AIM) 7-3. Termination I between 12.5 and 11.75 cal ka BP is defined by a monotonic increase in κARM, through the Younger Dryas (YD) chronozone and mirroring the EPICA ice core δ18O transition out of the Antarctic Cold Reversal. A simple phenomenological model is derived from the positive linear relationship (r = 0.86; n = 21; p = 1 x 10-6) of κARM and water depth on the continental shelf. Hydrodynamic sorting is inferred to be the primary process. Rock magnetic paleobathymetry has potential to provide quantitative constraints on estimates of water depth changes in, for example, shallow glacimarine settings. Together, the cores record most of the past two million years of oceanographic and climatic change at these sites, including tight connections between cooling/warming in New Zealand and Antarctica on timescales as short as 1000 years. This implies climate signals are rapidly communicated through both the ocean and atmosphere. OURArchive handle The handle from the Otago University Research Archive (OURArchive) <a href="http://hdl.handle.net/10523/1840">http://hdl.handle.net/10523/1840</a> OURArchvive access level Abstract Only Department The department where the student is studying primarily. Geology Named locality Named locality describing the field area location. New Zealand sector of the South Pacific Thesis description Number of pages, maps, CDs, etc. xviii, 256 p. : ill., maps ; 30 cm + 1 DVD-ROM (4 3/4 in.) 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 2010Nelson Creator An entity primarily responsible for making the resource Nelson, Faye Elizabeth. 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 Paleomagnetic records of the last two million years of climate and oceanographic change in the New Zealand sector of the South Pacific Subject The topic of the resource Marine geology paleomagnetism Relative paleointensity Tasman Sea https://theses.otagogeology.org.nz/files/original/4aa1c0f4ba660f9d80328f4506c689e4.pdf f880c6be46d9fe9ab2d5b74164c089e6 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 Henne Project type Is it an MSc, PhD, BSc(Hons) or PGDipSci? BSc(Hons) Advisers Who supervised/advised this student MacKenzie, D. Abstract The Abstract for this thesis The Fiddlers Flat section is a steep gorge cut into basement rocks and Tertiary sediment cover by the Manuherikia River downstream of Falls Dam in Central Otago, New Zealand. The river section exposes little-metamorphosed Torlesse Terrane sediments and their metamorphic equivalent, the Otago Schist with textural grades I, IIA, liD and Ill. Sediments overlying the Miocene unconformity that cut into the basement schist host a famous vertebrate fossil locality. The project uses field observations, petrography and geochemistry to produce a detailed structural section through the Otago schist margin exposed along the Fiddlers Flat section. This provides a structural setting for the aforementioned Miocene fossil locality and tests the hypothesis that argillite serves as a precursor to gold-bearing schist such as that which hosts the Macraes mine. The study area is ideal for this, because it contains all the typical structural characteristics of the metamorphosed Torlesse Terrane and provides a section showing a gradual increase in textural zone towards higher metamorphic grade Otago Schist in the SW. The geochemical composition of pelitic rocks from all textural zones at Fiddlers Flat, compared to unmineralised schist from Macraes and Oturehua, suggests that the unmineralised schist is Torlesse-derived. The geochemical comparison of Fiddlers Flat mineralised pelitic rocks with mineralised schist from Macraes identified some correlation but clearly indicated that Macraes rocks underwent an additional alteration process and/or mineralisation. Furthermore, Fiddlers Flat meta-pelites display two features characteristic of nearby gold-deposits: (1) post-metamorphic ankeritic alteration associated with argillitic material is similar to hydrothermal alteration occurring at Oturehua and (2) the high graphite content is similar to that found in Macraes intrashear schist. However, Macraes graphite is post-metamorphic while graphite at Fiddlers Flat was added pre- or syn-metamorphic and has distinctly higher values (up to 11.91 wt.%). Observations of changes in the textures and the amount of pyrite and graphite with increasing strain are used to make inferences about possible protolith-hydrothermal fluid interactions. 111 ,, ' il ! I The results of this study highlight that structural and chemical properties of rocks are important for post-diagenetic Au-mineralisation. These properties include (1) high permeability and (2) graphite enrichment. Two lithologies at Fiddlers Flat have these properties: a sheared TZ IIA meta-pelite and a pyrite-rich TZ liB meta-pelite. Both lithologies localise graphitisation, sulphidation, ankeritic alteration and tectonic deformation. The occurrence of graphitised TZ IIA rock and ungraphitised TZ IIA rock within a single complex tectonosome is the first genetic link between lithologies altered by graphite. Argillaceous rocks at Fiddlers Flat are structurally weak and chemically highly reactive and therefore more favourable for hydrothermal alteration than any other lithology observed. Data presented in this dissertation suggest that the protolith of Macraes mineralised micaceous schist may be genetically related to argillites of the Torlesse Terrane and that a complex interplay ofprotolith-fluid interaction is necessary in order to precipitate minerals. Department The department where the student is studying primarily. Geology Named locality Named locality describing the field area location. Manuheriikia River Thesis description Number of pages, maps, CDs, etc. ix, 195, [14] p. : 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 2010Henne Creator An entity primarily responsible for making the resource Henne, Anicia Ingrid 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 Structural evolution of the north-eastern Otago schist margin, New Zealand Subject The topic of the resource Petrology geochemistry gold Otago Schist Torlesse Terrane https://theses.otagogeology.org.nz/files/original/c15d785855b0360f00bf60b87ec7e211.pdf 1572be8af644bf3c2653ab88ee3f0184 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 ((170.295735541484419 -43.350403269862205,170.238085269528568 -43.307929944315816,170.285925826728345 -43.277510289429905,170.343279238508615 -43.317570420552364,170.295735541484419 -43.350403269862205)) Author last name Last name of the Author Easterbrook-Clarke Project type Is it an MSc, PhD, BSc(Hons) or PGDipSci? MSc Advisers Who supervised/advised this student Norris, R.J. Toy, V.G. Abstract The Abstract for this thesis The Alpine Fault, the main onshore structure in the Pacfic-Australian plate boundary, runs along the West Coast of the South Island of New Zealand, where it accommodates ~70% of the relative plate motion. The fault accommodates dextral reverse oblique slip with 23 - 25 mm/yr strike slip and up to 10 mm/yr of dip slip. The structure of the Alpine Fault zone at the surface can be divided into two parts: (1) the range front structure which comprises faults and other features that have developed within the top few kilometres and (2) the mylonite zone structure which preserve features developed in the shear zone at depth and have been uplifted along the fault. The study focuses on the range front structure of the Alpine Fault zone along the Waitangi-taona River, an area which covers a section approximately 6 km wide along strike of the Alpine Fault. Three parallel creek sections that feed into the Waitangi-taona River and the Waitangi-taona River headwaters, expose some of the most complete sections perpendicular to and through the fault rock sequence of the Alpine Fault. Mapping and characterisation of the mylonite zone structure found that protolith variation has a strong influence on the characteristics of structural features developed including S-C’ shear bands. A field-based classification scheme for Alpine Fault mylonites is presented that incorporates the field observations made in this study. A map of the entire field area at 1:20,000 and larger scale (1:2,000) maps and cross sections of the creek sections were produced. Additionally 3D maps of the fault zone structure and fault zone transitions were made using the field data. An increased thickness of the mylonite zone at the Waitangi-taona headwaters was identified. This is thought to be primarily related to imbrication of the mylonite sequence as it is thrust out shallowly onto gravels. The range front structure was examined by combining field studies with remote sensing techniques such as aerial and satellite imagery. Two subvertical faults were identified that are sub-parallel or at a small angle (≤25°) to the 060° striking basal thrust of the Alpine Fault. These faults are found within 100 m south-east of the basal thrust (i.e. in the hanging-wall) and are thought to form in response to shallow thrusting of the hanging-wall out onto the range-front. The slip direction on these faults should lie parallel to the basal thrust, such that juxtaposition of footwall against hangingwall rocks does not occur. Anisotropy of Magnetic Susceptibility studies were conducted on samples of fault gouge collected from the two sub-vertical faults and the Alpine Fault basal thrust. In this study AMS was found to be a useful proxy for penetrative gouge fabric elements forming at an angle to the gouge zone boundary, and a useful indicator for fault shear sense and direction. The most robust indicator for shear sense and direction was found to be the planar AMS fabric (the AMSF fabric). The source of the AMS fabric in the matrix is thought to be a combination of clay fabric (preferred basal orientation of phyllosilicates) and iron oxides. In some of the thin sections of fault gouge, and in one fault outcrop, ultramylonite clasts and the foliation within them were found to be aligned within the gouge zone (Foliation in Clast Preferred Orientation: F-CPO). This is also thought to contribute to the AMS. In most cases the AMSF shear direction was consistent with the shear direction from slickenside striations. On one of the sub-vertical faults (the `MacDonalds-Galaxiid sub-vertical segment') the AMSF fabric had a shear direction close to being within the basal thrust, whereas the slickenside striations on this fault plunged 40/244°. Slickenside striations likely reflect the last increment of shear, whereas the AMSF data provide a time averaged bulk shear direction. In this case the change in kinematics for this fault is thought to come about as it is thrust out shallowly in the near surface. OURArchive handle The handle from the Otago University Research Archive (OURArchive) <a href="http://hdl.handle.net/10523/1693">http://hdl.handle.net/10523/1693</a> OURArchvive access level Open Department The department where the student is studying primarily. Geology Named locality Named locality describing the field area location. Alpine Fault Waitangi-taona River Thesis description Number of pages, maps, CDs, etc. xi, 211 leaves : col. ill, col. maps ; 30 cm. + CD-ROM (4 3/4 in.) 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 2010Easterbrook-Clarke Creator An entity primarily responsible for making the resource Easterbrook-Clarke, Luke Hayhoe 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 The Alpine Fault Zone Along the Waitangi-taona River, West Coast, New Zealand Subject The topic of the resource Structural geology Alpine Fault AMS Fault Fault gouge Geology structure Waitangi-toana River