HR: 1340h
AN: PP23B-1422    [Abstracts]
TI: A revised shallow-marine global stratigraphic template for Quaternary glacio-eustatic sea-level fluctuations from Wanganui Basin, New Zealand
AU: * Naish, T
EM: t.naish@gns.cri.nz
AF: Insitute of Geological and Nuclear Sciences, PO Box 30368, Lower Hutt, 0000 New Zealand
AU: Carter, B
EM: Bob.carter@jcu.edu.au
AF: James Cook University, Private Bag, Townsville, QLD 4811 Australia
AU: Abbott, S
EM: sabbott@scu.edu.au
AF: Southern Cross University, Private Bag, Lismore, NSW 2480 Australia
AU: Field, B
EM: b.field@gns.cri.nz
AF: Insitute of Geological and Nuclear Sciences, PO Box 30368, Lower Hutt, 0000 New Zealand
AU: Zhu, H
EM: h.zhu@gns.cri.nz
AF: Insitute of Geological and Nuclear Sciences, PO Box 30368, Lower Hutt, 0000 New Zealand
AU: Wilson, G
EM: gary.wilson@stonebow.otago.ac.nz
AF: University of Otago, PO Box 56, Dunedin, 0000 New Zealand
AU: Alloway, B
EM: b.alloway@gns.cri.nz
AF: Insitute of Geological and Nuclear Sciences, PO Box 30368, Lower Hutt, 0000 New Zealand
AU: Edwards, S
EM: bob.carter@jcu.edu.au
AF: James Cook University, Private Bag, Townsville, QLD 4811 Australia
AU: Pillans, B
EM: brad.pillans@anu.edu.au
AF: The Australian National University, Private Bag, Canberra, ACT 0200 Australia
AU: Barker, A
EM: gary.wilson@stonebow.otago.ac.nz
AF: University of Oxford, Department of Earth Parks Road, Oxford, OX1 3PR United Kingdom
AU: Niessen, F
EM: fniessen@awi-bremerhaven.de
AF: Alfred-Wegener-Institute of Polar and Marine Research, P.O. Box 120161, Bremerhaven, 27515
AU: Maslen, G
EM: g.maslen@gns.cri.nz
AF: Insitute of Geological and Nuclear Sciences, PO Box 30368, Lower Hutt, 0000 New Zealand
AU: Beu, A
EM: a.beu@gns.cri.nz
AF: Insitute of Geological and Nuclear Sciences, PO Box 30368, Lower Hutt, 0000 New Zealand
AB: Wanganui Basin, New Zealand, contains one of the most complete Quaternary stratigraphic records in the world. The ca. 2 km thick basin-fill for the last 2.6 Ma comprises 44 superposed 5th- and 6th-order shallow marine sedimentary cycles which correspond to individual 100 ka and 41 ka sea-level cycles since oxygen isotope stage 100. Stages 100 to 5 are represented by marine cyclothems, whereas stages 17 to 4 are represented by a suite of coeval and younger uplifted marine terrace sequences. The Milankovitch-frequency, shallow marine, cyclostratigraphy of Wanganui Basin is here correlated with the astronomically-calibrated oxygen isotope Plio-Pleistocene timescale. The presence of interbedded tephras and an established paleomagnetic stratigraphy allows the development of an integrated cyclostratigraphy for Wanganui Basin which correlates closely with the global oxygen isotope sea-level proxy. Lithogical and faunal variation in the cyclothems correspond closely to that predicted by the sequence stratigraphic model. Each sea-level cycle is represented by individual depositional sequence comprising transgressive (TST), highstand (HST), and regressive systems tracts (RST). In general, major sedimentary facies within the basin fill were deposited in a range of coastal plain, shoreface, and shelf marine environments during the rise, highstand and falling part of each glacio-eustatic cycle. Glacial stages are represented by regressive shoreline facies that are truncated above by surfaces of marine planation and bioerosion, and that mark both cyclothem and sequence boundaries. Here we present a revised astronomically calibrated cyclostratigraphy from Wanganui Basin using high-resolution outcrop, borehole and seismic records.
DE: 4200 OCEANOGRAPHY: GENERAL
DE: 3000 MARINE GEOLOGY AND GEOPHYSICS
DE: 1600 GLOBAL CHANGE (New category)
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2004 AGU Fall Meeting