1 10 2 https://theses.otagogeology.org.nz/files/original/09f237e8b73fd6ed8afde68a2b2f2d0d.pdf ed13a3b6be84dbb2227ea246283736d2 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 ((170.995622179000065 -42.980229904999931,170.981263256000034 -42.989460644999951,170.982336461000045 -42.989479682999956,170.949548549000042 -43.010917973999938,170.9265565500001 -43.025936718999958,170.901371843000106 -43.042373964999967,170.884061017000022 -43.051589888999956,170.852974014000097 -43.06812612899995,170.849894831000029 -43.069763086999956,170.808608555000092 -43.091694935999953,170.804792259000124 -43.093752638999945,170.804869497000027 -43.089064707999967,170.804817125000113 -43.07528831299993,170.804766139000094 -43.061880357999939,170.804690317000109 -43.041949072999955,170.804658107000023 -43.033485111999937,170.804647756000122 -43.030765262999978,170.825590727000076 -43.018724133999967,170.844727264000085 -43.007713959999933,170.876134179000019 -42.989628402999983,170.879634138000029 -42.987611773999959,170.879777458000035 -42.987614445999952,170.888252189000013 -42.981036984999946,170.913156392000019 -42.969611768999982,170.95772458700003 -42.949140859999943,170.969687170000043 -42.943640897999956,170.974742980000087 -42.941315738999947,171.05443300100012 -42.90461292599997,171.088259788000073 -42.88900289299994,171.107074162000117 -42.880315888999974,171.108273963000102 -42.879761536999979,171.156570521000049 -42.857427791999953,171.288547467000058 -42.789149635999934,171.339713570000072 -42.763658160999967,171.345974838000075 -42.760535690999973,171.348868068000115 -42.763670563999938,171.352119868000045 -42.767193491999933,171.355133165000098 -42.770457593999936,171.356818636000071 -42.772283167999944,171.361741242000107 -42.777614204999963,171.35489524500008 -42.78133470299997,171.349934961000031 -42.78402985799994,171.340282010000124 -42.789273458999958,171.287590427000055 -42.817865887999972,171.27837442800012 -42.822688826999979,171.149662341000067 -42.889888560999964,171.129813828000124 -42.900225039999953,171.128653194000094 -42.900829244999954,171.127817192000066 -42.901264436999952,171.120209101000114 -42.90522436599997,171.088818462000063 -42.921551922999981,171.079310169000109 -42.926494088999959,171.07806430800008 -42.927141536999954,171.075868561000107 -42.928557465999972,171.006112721000022 -42.97348305,170.995622179000065 -42.980229904999931),(170.9176756170001 -42.988314537999941,170.958088844000031 -42.989047082999946,170.879927999000074 -42.987617250999961,170.9176756170001 -42.988314537999941)) Author last name Last name of the Author Rattenbury Project type Is it an MSc, PhD, BSc(Hons) or PGDipSci? PhD Advisers Who supervised/advised this student Norris, R.J. Cooper, A.F. Abstract The Abstract for this thesis Fraser Complex, replacing Fraser Formation, is a variably mylonitised suite of diverse igneous and high-grade metamorphic rocks in central Westland, New Zealand. Fraser Complex is bounded to the east by the Alpine Fault against Alpine schist of the Older Torlesse Terrane, and bounded to the west by the Fraser Fault and the Bald Hill Range Thrust against Karamea Terrane Greenland Group, granitoids and Cenozoic sediments. Interlayered amphibolite facies gneisses from Fraser Complex are collectively known as Mt Misery Metamorphic Suite, comprising the metapelitic garnet+biotite+sillimanite±kyanite±K-feldspar Hokitika Gneiss, the metabasic hornblende±epidote±biotite±garnet Doctor Creek Gneiss, and the migmatitic biotite+K-feldspar±garnet Hokitika Gneiss. The variability of garnet-biotite and garnet-hornblende geotherrnometry is attributed to retrogressive effects. Intrusive into Mt Misery Metamorphic Suite are Fraser Peak Granite and Doughboy Tonalite, S-type granitoids which are chemically distinct from Karamea and Separation Point Batholith granitoids, and have probably derived from melting of Hokitika Gneiss. Camptonite lamprophyre, trachyte and basalt dykes intrude Mt Misery Metamorphic Suite, Fraser Peak Granite and Dough boy Tonalite. Most of the dykes have a similar mineralogy and geochemistry to Hohonu Range dykes and may be early Cretaceous also. Enveloping Mt Misery Metamorphic Suite and igneous lithologies are numerous mylonite zones. Mylonitisation does not increase in intensity towards either the Alpine Fault or the Fraser Fault. Mylonite foliation generally dips steeply to the southeast, striking subparallel to the Alpine Fault trend. Mylonitic lineations generally plunge gently NE or SW, and the variability is attributed largely to sheath folding. Microstructural shear senses are predominantly dextral, although deformation is inhomogeneous. Mylonite protolithology can usually be sourced to Mt Misery Metamorphic Suite, Fraser Peak Granite or dyke lithologies. Albite-chlorite-actinolite-titanite, with some biotite recrystallisation, and deformation/recrystallisation of quartz and feldspar indicates mid greenschist facies conditions during mylonitisation. Mylonitisation postdates all dyke intrusions with one known exception, a basaltic dyke which truncates mylonite foliation and gives a minimum age of mylonitisation of late Miocene. The basaltic Smith Gorge dyke intrudes Doctor Creek Gneiss, not mylonite. Intrusion of lamprophyre, trachyte and most basalt dykes gives a maximum age of mylonitisation, of early-mid Cretaceous, rather than a minimum age as previously believed. High-grade gneisses occur throughout Westland and share similar metamorphic grade and mineralogy with Fraser Complex. Regional correlation of the gneisses as basement to Cambro-Ordovician Greenland Group is challenged by a 158 Ma U-Pb zircon age interpreted to date highgrade metamorphism of Fraser Complex. K-Ar dating of Fraser Complex gneisses and mylonites has indicated excess argon contributions to hornblende ages of 228-298 Ma, and possibly to whole rock ages of 45-91 Ma and to biotite ages of 44-61 Ma. The K-Ar biotite ages are incompatible with mid greenschist facies conditions during dextral strike-slip mylonitisation associated with Alpine Fault movement in the mid-late Tertiary. Uplift of Fraser Complex occurred along the Fraser Fault around 9 Ma, and ceased before deposition of Pliocene silts and conglomerates. The Fraser Fault is a steeply dipping zone of cataclasite, and is redefined to exclude locally crosscutting thrust faults. Initiation of movement and rapid uplift along the Bald Hill Range Thrust is recorded in Shadow Formation, a late Quaternary, periglacial marine silt and conglomerate sequence. Thrust surfaces underlying schist nappes up to 2 km northwest of the most recent Alpine Fault trace, with the Bald Hill Range Thrust are believed to be older, now inactive surface traces of the Alpine Fault which have migrated with time. Newly-discovered recent traces of the Alpine Fault show thrusting of Alpine schist over recent gravels. Two successively-underthrust gravels from Kaka Creek yielded radiocarbon ages of 3350 and 2600 years B.P., and give a minimum convergence rate across the Alpine Fault of 6.7 ± 1.5 mm/year. These ages extend an apparent 500 year return interval of large earthquakes in a relatively aseismic portion of the Alpine Fault. OURArchive handle The handle from the Otago University Research Archive (OURArchive) <a href="http://hdl.handle.net/10523/3459">http://hdl.handle.net/10523/3459</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. Westland central Thesis description Number of pages, maps, CDs, etc. xiii, 178 p Photos and Illus; 30cm. 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 1988Rattenbury Creator An entity primarily responsible for making the resource Rattenbury, Mark Sinclair Date A point or period of time associated with an event in the lifecycle of the resource 1988 Title A name given to the resource Fraser complex and alpine fault tectonics, central Westland, New Zealand Subject The topic of the resource Map Structural geology Metamorphic geology Igneous petrology Tectonics Alpine Fault Fraser Complex geochronology mylonitisation neotectonics https://theses.otagogeology.org.nz/files/original/9d35ce56d9e030408b577e2c62f7f3a6.pdf 5b1fcef94b00f41d957b6cf3461b44a2 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 ((169.843932088292917 -44.865329939080048,169.8506967159542 -44.750475080303403,169.9595647268508 -44.749140835097755,169.956916995764857 -44.866255759474939,169.843932088292917 -44.865329939080048)) Author last name Last name of the Author Hughes Project type Is it an MSc, PhD, BSc(Hons) or PGDipSci? BSc(Hons) Advisers Who supervised/advised this student Koons, P. Abstract The Abstract for this thesis Gravity models provide evidence for extensive thrusts on two fault systems in the Hawkdun Basin. Central Otago. These sets of faults trend northwest and northeast and are referred to as the Hawkdun and Manuherikia Fault Systems respectively. The gravity profiles also reveal significant basement topography which is related to these faults. The orientation of the basin margins departs from northeast and northwest trends where the Hawkdun and Manuhenkia faults do not control the range-fronts. Gravity profiles indicate low-angle sediment/ basement transition in these areas which may be original sedimentological contacts. Truncation of the northeasterly trending faults by those which trend northwest, an observation which is supported by 1:1M and 1:250 000 Bouguer anomaly maps, implies that the northwesterly trending faults were generated earlier and/or are deeper seated. Problems in removing the regional variation from the observed gravity wavelength of the values are complicated by the structures controlling the basin and structures which influence the regional gravity field. The bulk density of the sediment infilling the basin compared to the basement rock is the critical parameter tor gravity interpretation. This density contrast ranges from 0.86 to 0.6Mg/m3 based on electric drill logs. Despite constraints from these logs on density and depth to basement under the sediment, the models presented do not always fit the observed residuals. It is concluded that the problem with regional removal is compounded by three-dimensional effects from complex lateral density changes in the Hawkdun Basin. The Hawkdun and Manuherilda thrusting fault systems revealed by this study are the expression of the continuing compressional tectonic regime in New Zealand caused by the collision of the Indian and Pacific plates. Strain measurements from other regions in the South Island suggest that both sets of faults are currently active. Department The department where the student is studying primarily. Geology Named locality Named locality describing the field area location. Hawkdun Basin Thesis description Number of pages, maps, CDs, etc. 64 leaves : 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 1984Hughes Creator An entity primarily responsible for making the resource Hughes, S. L. M. Date A point or period of time associated with an event in the lifecycle of the resource 1984 Title A name given to the resource Gravity survey of the Hawkdun basin. Subject The topic of the resource Coal geology Geophysics Tectonics basin evaluation gravity survey neotectonics thrust faulting