https://theses.otagogeology.org.nz/files/original/f5cc77cc64d8e790b1fb065244349860.pdf 9b12c00415da53d6f0b29f52a3938748 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 ((169.449001255111398 -45.233334970424167,169.446825321401917 -45.278995759185221,169.381480173370534 -45.277417866292026,169.39850970053277 -45.232228257690274,169.449001255111398 -45.233334970424167)) Author last name Last name of the Author Yeo Project type Is it an MSc, PhD, BSc(Hons) or PGDipSci? MSc Advisers Who supervised/advised this student Craw, D. Mackenzie, D. Scott, J.M. Abstract The Abstract for this thesis A zone of brittle faults, hosted within the Otago Schist occurs along the NE- trending margin of the Manuherikia valley in Central Otago. The faults were initiated in the Cretaceous with predominantly normal sense of motion. Some faults have been reactivated as reverse structures since the Miocene, offset- ting gold-bearing Cenozoic sediments. Quaternary reactivation has resulted in stepped topography adjacent to the Manuherikia River. Cretaceous fault activity was accompanied by hydrothermal fluid flow and minor alteration of fault rocks and adjacent wall rocks. There are three different styles of faulting within the Tucker Hill area: narrow E-W orientated silicified zones, wide NE-SW orien- tated silicified cataclasite zones, and carbonate-rich, orange-stained zones. The narrow E-W oriented silicified zones have 5-10 cm wide silicified cataclasites along the fault plane, and these dominate the southern end of the area. Some of these zones host veins with euhedral crystals of calcite and quartz. These nar- row zones have a wide range of orientations, often show cross-cutting relation- ships with other faults and are traceable for only short distances (<100 m) along strike. Farther north in the area, wide resistant, silicified slabs of cataclasite, be- tween 2-4 metres across, form resistant ridges across topography. These zones are well exposed, with prominent fault planes containing slickenlines which pre- dominately show a dip-slip sense of motion. These large resistant faults range from moderately to steeply dipping and are largely orientated NE-SW. Inferred fault zones are prominently orange-stained where Fe-rich calcite has been al- tered to limonite, and form easily-eroded lower topographic features within the area such as gullies or saddles between ridges. These inferred fault zones are often associated with remnant Miocene, Dunstan Formation sediments. Some of the inferred zones occur along the same strike as the wide silicified catacla- site zones. Scattered pyrite occurs in some silicified rocks, and there are low but anomalous levels of arsenic and gold in some fault rocks. Two morphologically distinct types of Otago Schist basement have been described at Tucker Hill. The southern section contains a TZIII ”slabby” schist, whereas the northern section has a TZIV ”folded” schist. OURArchive handle The handle from the Otago University Research Archive (OURArchive) <a href="http://hdl.handle.net/10523/6138">http://hdl.handle.net/10523/6138</a> OURArchvive access level Open Access Department The department where the student is studying primarily. Geology Named locality Named locality describing the field area location. Manuherikia Fault Zone Alexandra Central Otago Thesis description Number of pages, maps, CDs, etc. xiv, 120 pages A4, A1 map in back pocket folded 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 2015Yeo Creator An entity primarily responsible for making the resource Yeo, Samantha Louise (Sam) Date A point or period of time associated with an event in the lifecycle of the resource 2015 Title A name given to the resource A Structurally Controlled Hydrothermal System in the Manuherikia Fault Zone, Alexandra, Central Otago Subject The topic of the resource Metamorphic geology Metal-ore depsoits Fault Zone mineralisation Otago Schist