Canterbury Drifts at Ocean Drilling Program Site 1119, New Zealand; climatic modulation of Southwest Pacific intermediate water flows since 3.9 Ma

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doi: 10.1130/G20783.1
Author(s): Carter, R. M.; Fulthorpe, C. S.; Lu, H.
Author Affiliation(s): Primary:
James Cook University, Marine Geophysical Laboratory, Townsville, Queensl., Australia
University of Texas at Austin, United States
Volume Title: Geology (Boulder)
Source: Geology (Boulder), 32(11), p.1005-1008. Publisher: Geological Society of America (GSA), Boulder, CO, United States. ISSN: 0091-7613 CODEN: GLGYBA
Note: In English. Includes 1 insert. 34 refs.; illus., incl. sketch map
Summary: We provide a record of variations in southwest Pacific Ocean intermediate water flow that shows a strong correlation between periods of vigorous flow and warm climate phases. Ocean Drilling Program Site 1119, located at 395 m water depth on the upper continental slope east of New Zealand, penetrated 514 m of silts and silty clays (glacial deposits) punctuated by muds and episodic 0.02-1.2-m-thick terrigenous sands (interglacial deposits). The natural gamma-ray record reflects the waxing and waning of the South Island ice cap since 3.91 Ma. Below 86.19 m composite depth, the succession comprises drift sediments deposited from north-flowing intermediate Subantarctic Mode Water (SAMW, ∼250-800 m depth) and Antarctic Intermediate Water (∼800-1100 m depth). A change from the deposition of large, low-energy drifts on the middle slope to smaller, higher-energy drifts on the upper slope coincided with global climatic deterioration that occurred after ca. 3.25 Ma. This change marks an upward expansion of intermediate cold waters, perhaps caused by the inception of the Subantarctic Front and the consequent commencement of Southland Current-driven SAMW flow.
Year of Publication: 2004
Research Program: ODP Ocean Drilling Program
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; 20 Geophysics, Applied; Antarctic Intermediate Water; Australasia; Canterbury Drifts; Cenozoic; Clastic sediments; Clay; Climate change; Continental margin sedimentation; Continental slope; Cores; Depositional environment; Drift; Geophysical methods; Geophysical surveys; Glacial environment; Glaciomarine environment; High-resolution methods; Interglacial environment; Leg 181; Marine environment; Marine sediments; Mud; Multichannel methods; Neogene; New Zealand; ODP Site 1119; Ocean Drilling Program; Ocean circulation; Pacific Ocean; Paleo-oceanography; Paleocirculation; Paleoclimatology; Pliocene; Quaternary; Sedimentation; Sediments; Seismic methods; Slope environment; South Island; South Pacific; Southern Ocean; Southwest Pacific; Subantarctic Mode Water; Surveys; Tertiary; Upper Pliocene; West Pacific
Coordinates: S444520 S444520 E1722336 E1722336
Record ID: 2004084089
Copyright Information: GeoRef, Copyright 2017 American Geosciences Institute. Reference includes data supplied by the Geological Society of America, Boulder, CO, United States