Offshore transport of neritic diatoms as indicators of surface current and trade wind strength in the Plio-Pleistocene eastern Equatorial Pacific

Author(s): Kennington, Kevin; Haslett, Simon K.; Funnell, Brian M.
Author Affiliation(s): Primary:
University of Liverpool, Port Erin Marine Laboratory, Port Erin, Isle of Man, United Kingdom
Other:
Carleton University, Canada
University of Georgia, United States
Bath Spa University College, United Kingdom
University of East Anglia, United Kingdom
Volume Title: Taphonomy as a tool in paleoenvironmental reconstruction and environmental assessment
Volume Author(s): Martin, Ronald E., editor; Patterson, R. Timothy; Goldstein, Susan T.; Kumar, Arun
Source: Taphonomy as a tool in paleoenvironmental reconstruction and environmental assessment, edited by Ronald E. Martin, R. Timothy Patterson, Susan T. Goldstein and Arun Kumar. Palaeogeography, Palaeoclimatology, Palaeoecology, 149(1-4), p.171-181. Publisher: Elsevier, Amsterdam, Netherlands. ISSN: 0031-0182 CODEN: PPPYAB
Note: In English. 28 refs.; illus., incl. 2 tables, sketch map
Summary: The taphonomy of neritic diatoms entrained into, and transported offshore by, the Peru and South Equatorial currents may represent fluctuations in surface current and southeast trade wind strength in the eastern equatorial Pacific (EEP). This proposition was investigated through the construction of a neritic/pelagic diatom ratio (NPDR) which is compared with other palaeoceanographic proxies analysed through the Olduvai timeslab (ca. 2.0-1.75 Ma) at Ocean Drilling Program sites 677, 847 and 851: a new sea-surface temperature (SST) record for all the sites is derived from a diatom transfer function, and upwelling and bioproductivity records are provided by previously published radiolarian and CaCO3 data, respectively, for site 677 only. Results indicate a consistent relationship between proxy records, suggesting that the presence of neritic diatoms in pelagic sediments are most likely attributable to surface current and trade wind variability. The NPDR has the potential of becoming an extremely useful micropalaeontological tool in multi-proxy palaeoceanographic studies of coastal upwelling systems. The palaeoceanographic history of the Olduvai timeslab in the EEP, as indicated by previous studies, is supported and enhanced by the NPDR and new SST data reported here. The early and late periods of the Olduvai timeslab are characterised by strong upwelling, low SST, and high bioproductivity, and increased trade wind strengths inferred from the NPDR. The mid-Olduvai (1.80-1.90 Ma) appears to have been a period of weaker upwelling, higher SSTs, lower bioproductivity and decreased trade wind strength as indicated by the NPDR. The NPDR is important as it increases our understanding of the relationship between palaeoceanographic processes and trade wind strength in the region. Abstract Copyright (1999) Elsevier, B.V.
Year of Publication: 1999
Research Program: ODP Ocean Drilling Program
Key Words: 07 Marine Geology and Oceanography; Algae; Bioclastic sedimentation; Calcium carbonate; Cenozoic; Coastal environment; Diatoms; Equatorial Pacific; Invertebrata; Leg 111; Leg 138; Marine environment; Marine transport; Neogene; ODP Site 677; ODP Site 847; ODP Site 851; Ocean Drilling Program; Pacific Ocean; Paleo-oceanography; Paleocirculation; Paleocurrents; Pelagic environment; Plantae; Pleistocene; Pliocene; Protista; Quaternary; Radiolaria; Sea-surface temperature; Sedimentation; Subtidal environment; Taphonomy; Tertiary; Trade winds; Upwelling
Coordinates: N024612 N024614 W1103417 W1103419
Record ID: 1999068363
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from CAPCAS, Elsevier Scientific Publishers, Amsterdam, Netherlands