Role of Panama uplift on oceanic freshwater balance

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doi: 10.1130/0091-7613(2001)029<0207:ROPUOO>2.0.CO;2
Author(s): Haug, Gerald H.; Tiedemann, Ralf; Zahn, Rainer; Ravelo, A. Christina
Author Affiliation(s): Primary:
Eidgenössische Technische Hochschule, Department of Earth Sciences, Zurich, Switzerland
Other:
Geomar, Kiel, Federal Republic of Germany
Cardiff University, Cardiff, United Kingdom
University of California at Santa Cruz, United States
Volume Title: Geology (Boulder)
Source: Geology (Boulder), 29(3), p.207-210. Publisher: Geological Society of America (GSA), Boulder, CO, United States. ISSN: 0091-7613 CODEN: GLGYBA
Note: In English. 36 refs.; illus., incl. sketch map
Summary: Comparison between planktic foraminiferal oxygen isotope records from the Caribbean Sea (Ocean Drilling Program [ODP] Site 999) and the equatorial east Pacific (ODP Site 851) suggests an increase in Caribbean surface-water salinity between 4.7 and 4.2 Ma. The modern Atlantic-Pacific salinity contrast of about 1 per mil became fully established at 4.2 Ma as reflected by a 0.5 per mil planktic foraminifera 18O enrichment in the Caribbean Sea. This is interpreted as the result of restricted surface-water exchange between the tropical Atlantic and Pacific in response to the shoaling of the Central American seaway. As a consequence, the Atlantic and Pacific surface-ocean circulation regime changed, as did the freshwater balance between the major ocean basins. Simultaneous shifts in benthic carbon isotope records in the Caribbean Sea suggest an intensification in North Atlantic thermohaline circulation. These results indicate that the Panamanian isthmus formation caused several new ocean-atmosphere feedback mechanisms that have affected climate since the early Pliocene.
Year of Publication: 2001
Research Program: ODP Ocean Drilling Program
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; Atlantic Ocean; Biostratigraphy; Caribbean Sea; Cenozoic; Central America; Chemostratigraphy; East Pacific; Equatorial Pacific; Feedback; Foraminifera; Fresh water; Invertebrata; Isotope ratios; Isotopes; Leg 138; Leg 165; Marine sediments; Microfossils; Neogene; North Atlantic; O-18/O-16; ODP Site 851; ODP Site 999; Ocean Drilling Program; Oxygen; Pacific Ocean; Paleo-oceanography; Paleocirculation; Paleoclimatology; Paleocurrents; Paleogeography; Paleosalinity; Panama; Planktonic taxa; Protista; Salt water; Sediments; Stable isotopes; Tertiary; Thermohaline circulation; Tropical environment; Uplifts
Coordinates: N124437 N124437 W0784422 W0784422
N024612 N024614 W1103417 W1103419
Record ID: 2001021643
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data supplied by the Geological Society of America, Boulder, CO, United States