Sarnthein, Michael; Faugeres, Jean-Claude (1993): Median grain size and distribution of sand in ODP Hole 108-660A (Fig. 5) [dataset]. PANGAEA, https://doi.org/10.1594/PANGAEA.763684, Supplement to: Sarnthein, M; Faugeres, J-C (1993): Radiolarian contourites record Eocene AABW circulation in the equatorial East Atlantic. Sedimentary Geology, 82(1-4), 145-155, https://doi.org/10.1016/0037-0738(93)90118-O
Always quote citation above when using data! You can download the citation in several formats below.
Abstract:
50 m of Middle Eocene pure radiolarian ooze were drilled at ODP Site 660 in the equatorial East Atlantic, 80 km northeast of the Kane Gap. The oozes comprise a 10 m high and 2 km broad mound of seismic reverberations, covered by manganese-rich sediment, and contain trace amounts of sponge spicules and diatoms, negligible organic carbon (0.15%), clay, and variable amounts of pyrite. The yellow to pale brown silty sediments are relatively coarse-grained (30–45% coarser than 6 µm), little bioturbated, and commonly massive or laminated on a cm-scale.
The unlithified radiolarian ooze may indicate an interval of high oceanic productivity, probably linked to a palaeoposition of Site 660 close to the equatorial upwelling belt during Middle Eocene time. The absence of organic matter, however, and both the laminated bedding and the mound-like structure of the deposit on the lower slope of a continental rise indicate deposition by relatively intense contour currents of oxygen-rich deep water, which passed through the Kane Gap, winnowed the fine clay fraction, and prevented the preservation of organic carbon. The ooze may be either a contourite-lag deposit, or a contourite accumulation of displaced radiolarians, originating south of the Kane Gap and being deposited in its northern lee, thus documenting the passage of a strong cross-equatorial bottom-water current formed near Antarctica. These Eocene contourites may be an analogue for ancient radiolarites in the Tethyan Ocean.
Project(s):
Ocean Drilling Program (ODP)
Coverage:
Latitude: 10.013500 * Longitude: -19.245600
Date/Time Start: 1986-03-15T00:30:00 * Date/Time End: 1986-03-16T10:30:00
Minimum Elevation: -4343.0 m * Maximum Elevation: -4343.0 m
Event(s):
108-660A * Latitude: 10.013500 * Longitude: -19.245600 * Date/Time Start: 1986-03-15T00:30:00 * Date/Time End: 1986-03-16T10:30:00 * Elevation: -4343.0 m * Penetration: 164.9 m * Recovery: 163.74 m * Location: South Atlantic Ocean * Campaign: Leg108 * Basis: Joides Resolution * Method/Device: Drilling/drill rig (DRILL) * Comment: 19 cores; 164.9 m cored; 0 m drilled; 99.3 % recovery
Parameter(s):
# | Name | Short Name | Unit | Principal Investigator | Method/Device | Comment |
---|---|---|---|---|---|---|
1 | Sample code/label | Sample label | Sarnthein, Michael | DSDP/ODP/IODP sample designation | ||
2 | Median, grain size | D50 | µm | Sarnthein, Michael | ||
3 | Size fraction > 0.063 mm, sand | >63 µm | % | Sarnthein, Michael |
License:
Creative Commons Attribution 3.0 Unported (CC-BY-3.0)
Size:
90 data points