Radiolaria and pollen records from 0 to 50 ka at ODP Site 1233; continental and marine climate records from the Southeast Pacific

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doi: 10.1016/j.quascirev.2005.06.009
Author(s): Pisias, Nicklas G.; Heusser, Linda E.; Heusser, Cal J.; Hostetler, Steven W.; Mix, Alan C.; Weber, Mysti
Author Affiliation(s): Primary:
Oregon State University, College of Oceanic and Atmospheric Sciences, United States
Other:
Columbia University, United States
New York University, United States
U. S. Geological Survey, United States
Volume Title: Quaternary Science Reviews
Source: Quaternary Science Reviews, 25(5-6), p.455-473. Publisher: Elsevier, International. ISSN: 0277-3791
Note: In English. NSF grants ATM 0135294 and ATM 0319016. 31 refs.; illus., incl. 3 tables, sketch maps
Summary: Site 1233 drilled during Leg 202 of the Ocean Drilling Program provides a detailed record of marine and continental climate change in the Southeast Pacific and South American continent. Splits from over 500 samples taken at 20cm intervals for quantitative analysis of radiolarian and pollen populations yield a temporal resolution of 200-400 years. In each sample, 39 pollen taxa and 40 radiolarian species and genera were evaluated. Age control is provided by 25 AMS 14C dates [Lamy, F., Kaiser, J., Ninnemann, U., Hebbeln, D., Arz, H. W., Stoner, J., 2004. Science 304, 1959-1962]. Multivariate statistical analyses of these data allow us to conclude the following: (1) During the past 50 ka, the region of the central Chile coast is not directly influenced by polar water from the Antarctic region. (2) Changes in ocean conditions off central Chile during this time interval primarily reflect north-south shifts in the position of the South Pacific transition zone. (3) Changes in Chilean vegetation reflect comparable latitudinal shifts in precipitation and the position of the southern westerlies. (4) The first canonical variate of radiolarian and pollen records extracted from Site 1233 are remarkably similar to each other as well as to temperature records from the Antarctic, which suggests that marine and continental climate variability in the region is tightly coupled at periods longer than 3000 years. (5) The phase coupling of these climate records, which lead variations of continental erosion based on iron abundance at the same site, are consistent with a hypothesis that erosion is linked to relatively long (i.e, few thousand years) response times of the Patagonian ice sheet, and thus is not a direct indicator of regional climate.
Year of Publication: 2006
Research Program: ODP Ocean Drilling Program
Key Words: 24 Surficial Geology, Quaternary Geology; Absolute age; Accelerator mass spectra; Andes; Antarctica; Argentina; Assemblages; Biostratigraphy; C-14; Canonical analysis; Carbon; Cenozoic; Chile; Climate change; Dates; East Pacific; Glacial geology; Glaciation; Ice sheets; Invertebrata; Isotopes; Last glacial maximum; Leg 202; Marine environment; Mass spectra; Microfossils; Miospores; Multivariate analysis; ODP Site 1233; Ocean Drilling Program; Pacific Ocean; Paleo-oceanography; Paleoclimatology; Paleocurrents; Paleoenvironment; Palynomorphs; Patagonia; Pleistocene; Pollen; Protista; Quantitative analysis; Quaternary; Radioactive isotopes; Radiolaria; South America; South Pacific; Southeast Pacific; Spectra; Statistical analysis; Terrestrial environment; Upper Pleistocene
Coordinates: S410000 S410000 W0742700 W0742700
Record ID: 2006072429
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from CAPCAS, Elsevier Scientific Publishers, Amsterdam, Netherlands