The University of Southampton
University of Southampton Institutional Repository

Paleogene tropical Pacific: Clues to circulation, productivity, and plate motion

Paleogene tropical Pacific: Clues to circulation, productivity, and plate motion
Paleogene tropical Pacific: Clues to circulation, productivity, and plate motion
Stratigraphic data from 63 Deep Sea Drilling Project and Ocean Drilling Program (ODP) sites that sample the lower Neogene and Paleogene sediments of the tropical Pacific have been compiled and put on the biostratigraphic and paleomagnetic timescale refined by ODP Leg 199 scientists. Sediment accumulation rates have been calculated for ten intervals ranging in age from 10 to 56 Ma and have been plotted for the midpoint of each interval at the associated paleoposition for each site used. A fixed hot spot model was used for reconstruction of the Pacific lithospheric plate. All such reconstructed intervals show the development of a tongue of high accumulation rates associated with the oceanographic divergence at the geographic equator. The development of this equatorial band is weakest between 46 and 56 Ma, the time of the peak warmth in Paleogene climate. Possible motion of the Hawaiian hot spot or true polar wander between 46 and 56 Ma appears to have had little effect on the plate rotation estimate of the position of the equator. In addition to temporal changes in the calcite compensation depth and in productivity, the biggest change in the patterns of sediment accumulation rates in the eastern tropical Pacific was the development of a relatively strong divergence between 6° and 10°N, near the region of divergence between the modern North Equatorial Current and the North Equatorial Counter Current. Changes in the equatorial circulation appear to be associated in time with the opening and closing of oceanic gateways, particularly the complex closing of the Caribbean-Pacific gateway.
equatorial Pacific, Cenozoic, Ocean Drilling Project
PA3013
Moore, T.C.
7bbc9539-0103-4010-8a24-f31124baacfb
Backman, J.
b2d77581-60c6-44fd-b61e-9dfbd85f2a8f
Raffi, I.
5cd0b487-3cdc-48e6-894c-2bbf5c59ae02
Nigrini, C.
65f6f71b-fbe2-42ed-9dbb-003243790963
Sanfilippo, A.
46ba57e7-6b8d-421f-8281-1934c83df8bb
Pälike, H.
b9bf7798-ad8c-479b-8487-dd9a30a61fa5
Lyle, M.
32ca0536-0600-4193-bc16-70fbe8c99dd6
Moore, T.C.
7bbc9539-0103-4010-8a24-f31124baacfb
Backman, J.
b2d77581-60c6-44fd-b61e-9dfbd85f2a8f
Raffi, I.
5cd0b487-3cdc-48e6-894c-2bbf5c59ae02
Nigrini, C.
65f6f71b-fbe2-42ed-9dbb-003243790963
Sanfilippo, A.
46ba57e7-6b8d-421f-8281-1934c83df8bb
Pälike, H.
b9bf7798-ad8c-479b-8487-dd9a30a61fa5
Lyle, M.
32ca0536-0600-4193-bc16-70fbe8c99dd6

Moore, T.C., Backman, J., Raffi, I., Nigrini, C., Sanfilippo, A., Pälike, H. and Lyle, M. (2004) Paleogene tropical Pacific: Clues to circulation, productivity, and plate motion. Palaeoceanography, 19 (3), PA3013. (doi:10.1029/2003PA000998).

Record type: Article

Abstract

Stratigraphic data from 63 Deep Sea Drilling Project and Ocean Drilling Program (ODP) sites that sample the lower Neogene and Paleogene sediments of the tropical Pacific have been compiled and put on the biostratigraphic and paleomagnetic timescale refined by ODP Leg 199 scientists. Sediment accumulation rates have been calculated for ten intervals ranging in age from 10 to 56 Ma and have been plotted for the midpoint of each interval at the associated paleoposition for each site used. A fixed hot spot model was used for reconstruction of the Pacific lithospheric plate. All such reconstructed intervals show the development of a tongue of high accumulation rates associated with the oceanographic divergence at the geographic equator. The development of this equatorial band is weakest between 46 and 56 Ma, the time of the peak warmth in Paleogene climate. Possible motion of the Hawaiian hot spot or true polar wander between 46 and 56 Ma appears to have had little effect on the plate rotation estimate of the position of the equator. In addition to temporal changes in the calcite compensation depth and in productivity, the biggest change in the patterns of sediment accumulation rates in the eastern tropical Pacific was the development of a relatively strong divergence between 6° and 10°N, near the region of divergence between the modern North Equatorial Current and the North Equatorial Counter Current. Changes in the equatorial circulation appear to be associated in time with the opening and closing of oceanic gateways, particularly the complex closing of the Caribbean-Pacific gateway.

This record has no associated files available for download.

More information

Published date: 2004
Keywords: equatorial Pacific, Cenozoic, Ocean Drilling Project

Identifiers

Local EPrints ID: 13484
URI: http://eprints.soton.ac.uk/id/eprint/13484
PURE UUID: fc262327-5e67-46f3-8fa8-11c248b68837

Catalogue record

Date deposited: 08 Dec 2004
Last modified: 15 Mar 2024 05:07

Export record

Altmetrics

Contributors

Author: T.C. Moore
Author: J. Backman
Author: I. Raffi
Author: C. Nigrini
Author: A. Sanfilippo
Author: H. Pälike
Author: M. Lyle

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×