1 10 2 https://theses.otagogeology.org.nz/files/original/dd03fce1819dabbff5bdb46d34d544e2.pdf f48d7a7fbb26fdb3dea8d4c6935489c4 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 ((177.924471100987603 -38.772278405256273,177.742926978947139 -38.879873079522405,177.514840239542167 -38.5505827040664,177.950457959538682 -38.266097998443541,178.074902358298289 -38.403710453697812,178.013575887873088 -38.654126141049524,178.199419826415721 -38.703165793586237,178.016975242084413 -39.902318595318228,177.614373341393474 -39.895252266059423,177.924471100987603 -38.772278405256273)) Author last name Last name of the Author Quinn Project type Is it an MSc, PhD, BSc(Hons) or PGDipSci? MSc Advisers Who supervised/advised this student Wilson, G.S Abstract The Abstract for this thesis U-channel samples from seven cores collected from the Poverty Continental Shelf, East Coast, New Zealand, have been used in an environmental magnetic study of the Waipaoa sedimentary dispersal system, as part of the MARGINS Source to Sink (S2S) research programme. Magnetic measurements of K, NRM intensity, AF demagnetisation, ARM and IRM were performed on the u-channels and the results used to identify changes in magnetic mineralogy, magnetic concentration and magnetic grain size that occurred in the cores. Discrete parameters were identified from parametric ratios, biplots and King plots. Three sediment samples from the Waipaoa River were collected to provide a link between the magnetic signals observed in the sediment cores on the Poverty Shelf to the magnetic signature of sediment that is being discharged from land. Age control for the cores is provided by using tephra horizons and 210Pb accumulation rates. Tephra identified in the \ - CCA ~ ~A.c(a.r cores are the Taupo (1.718 ka), Mapara (2.10 ka) and Waimihia (3.47 ka) events. 210Pb ~,.e""'"-s accumulation rates vary widely over the Poverty Shelf area ranging 0.27-0.77 crnly. The dominant magnetic mineralogy of the cores is SD-PSD magnetite, with one core containing greigite, which formed during the quieter periods after three large storm events in the Waipaoa Catchment over the last ~350 years. Three outer shelf cores (K32, K54 and MD06- 3005) exhibit an increase in magnetic grain size and a decrease in magnetic concentration downcore at around 1.00 m depth. These magnetic variations are attributed to anthropogenic influence from deforestation during Polynesian settlement in the Waipaoa Catchment ~800- 900 years ago which resulted in increased erosion rates affecting the magnetic concentration and grain size. IRM variations in K47 at 0.60 m, indicating a slightly differing mineralogy, are attributed to a change in the dominant erosion style in the Waipaoa Catchment (landsliding versus gully erosion) as observed in MD97-2122. The magnetic stratigraphy of a core from the Hawke's Bay Slope (JPC56) is comparable with pollen records from nearby marine and lake cores suggesting the appearance and disappearance of certain taxa allows for varying erosion rates, erosion of different lithologies and weathering of soils. The magnetic signature of the Waipaoa River samples is similar to that of the Poverty Shelf cores. This indicates that the Waipaoa Catchment is a major source of the sediment deposited on the Poverty Shelf. Department The department where the student is studying primarily. Geology Named locality Named locality describing the field area location. Offshore Hawkes Bay Thesis description Number of pages, maps, CDs, etc. 134 leaves : ill., maps ; 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 2007Quinn Creator An entity primarily responsible for making the resource Alissa N. Quinn (Alissa Nicole), 1983- Date A point or period of time associated with an event in the lifecycle of the resource 2007 Title A name given to the resource Environmental magnetic signature of the Waipaoa system, offshore Hawkes Bay, over the last few millenia Subject The topic of the resource Paleomagnetics environmental magnetic methods magnetic intensity Source to sink stratigraphy https://theses.otagogeology.org.nz/files/original/733b8c8188598071534378719ec701f6.pdf 973164ddd0e73e9152a224dfbc4ac07c 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 Fitzgerald Project type Is it an MSc, PhD, BSc(Hons) or PGDipSci? PGDipSci Advisers Who supervised/advised this student Wilson, G.S. Abstract The Abstract for this thesis Environmental magnetic methods were used to determine the environmental history recorded in sediment cores (L - 1407 and L - 1408) collected from the bed of Lake Ohau, South Island, New Zealand. Fluctuating magnetic intensity in both cores exhibits 1 00 year periodicity interpreted to originate from palaeoclimatic cycles. Small magnetic intensity fluctuations possibly reflect El/Nino and La Nina cycles. Stratigraphy in both cores mainly comprises ,...ef'varves which provide a means for dating changes in environmental processes. Turbidites at 81 0 mm and 1810 mm in sediment core L - 1407 closely correlate with palaeoseismic events during September 1888 in North Canterbury and rupture of the Alpine Fault during 1717, respectively. Inclination and declination obtained from the processed data exhibits secular variation. From the constructed age models sediment cores L- 1407 and L - 1408 have a mean sedimentation rate of~ 8 mm/yr and~ 7 mm/yr, respectively. Department The department where the student is studying primarily. Geology Named locality Named locality describing the field area location. Ohau catchment Lake Ohau Thesis description Number of pages, maps, CDs, etc. vii, 62 leaves : col. ill., col. maps (some folded) ; 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 2004Fitzgerald Creator An entity primarily responsible for making the resource Fitzgerald, Shannon. Date A point or period of time associated with an event in the lifecycle of the resource 2004 Title A name given to the resource 250 year record of environmental cyclicity in the Ohau catchment : a sedimentary and palaeomagnetic study Subject The topic of the resource Sedimentology Geophysics environmental magnetic methods magnetic intensity