Sedimentology of the Rio Grande Rise area, supplement to: Gingele, Franz; Schmieder, Frank; von Dobeneck, Tilo; Petschick, Rainer; Rühlemann, Carsten (1999): Terrigenous flux in the Rio Grande Rise area during the last 1.5 Ma: evidence of deepwater advection or rapid response to continental rainfall patterns. Paleoceanography, 14(1), 84-95

• Main Authors: Gingele, Franz, Schmieder, Frank, von Dobeneck, Tilo, Petschick, Rainer, Rühlemann, Carsten
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA - Data Publisher for Earth & Environmental Science 1999
• Subjects: Gravity corer Kiel type; M23/2; M29/2; Meteor 1986; Geosciences, University of Bremen GeoB; Mid-Atlantic Ridge; North Atlantic Deep Water; North Atlantic
• Online Access: https://dx.doi.org/10.1594/pangaea.730524; https://doi.pangaea.de/10.1594/PANGAEA.730524

Surface sediment samples and three gravity cores from the eastern terrace of the Vema Channel, the western flank of the Rio Grande Rise, and the Brazilian continental slope were investigated for physical properties, grain size, and clay mineral composition. Discharge of the Rio Doce is responsible for kaolinite enrichments on the slope south of 20° and at intermediate depths of the Rio Grande Rise. The long-distance advection of kaolinite with North Atlantic Deep Water from lower latitudes is of minor importance as evidenced by low kaolinite/chlorite ratios on the Mid-Atlantic Ridge. Cyclic variations of kaolinite/chlorite ratios in all our cores, with maxima in interglacials, are attributed to low-and high-latitude forcing of paleoclimate on the Brazilian mainland and the related discharge of the Rio Doce. A long-term trend toward more arid and 'glacial' conditions from 1500 ka to present is superimposed on the glacial-interglacial cyclicity.