Not logged in
Data Publisher for Earth & Environmental Science

Friedrich, Oliver; Erbacher, Jochen; Moriya, Kazuyoshi; Wilson, Paul A; Kuhnert, Henning (2008): Stable oxygen isotope record and benthic foraminiferal abundances in Cretaceous sediments of Demerara Rise [dataset publication series]. PANGAEA,, Supplement to: Friedrich, O et al. (2008): Warm saline intermediate waters in the Cretaceous tropical Atlantic Ocean. Nature Geoscience, 1(7), 453-457,

Always quote citation above when using data! You can download the citation in several formats below.

RIS CitationBibTeX CitationShow MapGoogle Earth

During the mid-Cretaceous period, the global subsurface oceans were relatively warm, but the origins of the high temperatures are debated. One hypothesis suggests that high sea levels and the continental configuration allowed high-salinity waters in low-latitude epicontinental shelf seas to sink and form deep-water masses (Brass et al., 1982, doi:10.1038/296620a0; Arthur and Natland, 1979; Chamberlin, 1906). In another scenario, surface waters in high-latitude regions, the modern area of deep-water formation, were warmed through greenhouse forcing (Bice and Marotzke, 2001, doi:10.1029/2000JC000561), which then propagated through deep-water circulation. Here, we use oxygen isotopes and Mg/Ca ratios from benthic foraminifera to reconstruct intermediate-water conditions in the tropical proto-Atlantic Ocean from 97 to 92 Myr ago. According to our reconstruction, intermediate-water temperatures ranged between 20 and 25 °C, the warmest ever documented for depths of 500-1,000 m. Our record also reveals intervals of high-salinity conditions, which we suggest reflect an influx of saline water derived from epicontinental seas around the tropical proto-North Atlantic Ocean. Although derived from only one site, our data indicate the existence of warm, saline intermediate waters in this silled basin. This combination of warm saline intermediate waters and restricted palaeogeography probably acted as preconditioning factors for the prolonged period of anoxia and black-shale formation in the equatorial proto-North Atlantic Ocean during the Cretaceous period.
Median Latitude: 9.370458 * Median Longitude: -54.662169 * South-bound Latitude: 9.265667 * West-bound Longitude: -54.733050 * North-bound Latitude: 9.433333 * East-bound Longitude: -54.544033
Date/Time Start: 2003-01-22T00:00:00 * Date/Time End: 2003-02-12T00:00:00
207-1258 * Latitude: 9.433333 * Longitude: -54.733050 * Date/Time Start: 2003-01-22T00:00:00 * Date/Time End: 2003-02-01T00:00:00 * Elevation: -3192.2 m * Penetration: 1393.4 m * Recovery: 882.7 m * Location: South Atlantic Ocean * Campaign: Leg207 * Basis: Joides Resolution * Method/Device: Composite Core (COMPCORE) * Comment: 141 cores; 1116.6 m cored; 276.8 m drilled; 79 % recovery
207-1260 * Latitude: 9.265667 * Longitude: -54.544033 * Date/Time Start: 2003-02-07T00:00:00 * Date/Time End: 2003-02-12T00:00:00 * Elevation: -2548.8 m * Penetration: 1000.9 m * Recovery: 718.1 m * Location: South Atlantic Ocean * Campaign: Leg207 * Basis: Joides Resolution * Method/Device: Composite Core (COMPCORE) * Comment: 100 cores; 862.2 m cored; 138.7 m drilled; 83.3 % recovery
8 datasets

Download Data

Download ZIP file containing all datasets as tab-delimited text — use the following character encoding: