Clay and smectite content in sediment core CRP-3 ...

• Main Author: Ehrmann, Werner
• Format: Dataset
• Language: English
• Published: PANGAEA 2001
• Subjects: DEPTH, sediment/rock; Size fraction < 0.002 mm, clay; Smectite/standard ratio; Smectite; Smectite, integral width; Core wireline system; Grain size, sieving/settling tube; X-ray diffraction TEXTUR, clay fraction; CRP-3; Sampling/drilling from ice; Cape Roberts Project CRP; Antarc*; Antarctica; antartic*; McMurdo Sound; Ross Sea; Southern Ocean; Victoria Land
• Online Access: https://dx.doi.org/10.1594/pangaea.57868; https://doi.pangaea.de/10.1594/PANGAEA.57868

The Cenozoic sediments of the CRP-3 drill core from the continental shelf of McMurdo Sound in Ross Sea, Pacific sector of the Southern Ocean, have been investigated for their clay mineral assemblages, especially for the smectite abundances, concentrations and crystallinities. The assemblages of CRP-3 are very different from those of the CRP-1 and CRP-2/2A drill cores. Thus, an almost monomineralic assemblage characterizes the sequence below 330 mbsf. This assemblage is made of well-crystallized smectite with probably authigenic origin between 800 mbsf and 625 mbsf. From 625 mbsf to 330 mbsf the assemblage consists of moderately crystallized smectite that, at least in part, seems to be of detrital origin and thus indicates weathering under a relatively warm and wet climate. In the interval 330-145 mbsf, smectite concentrations fluctuate between 50% and 100% and probably document alternating phases of chemical weathering under a warm and wet climate and physical weathering under a relatively cool and dry ... : Supplement to: Ehrmann, Werner (2001): Variation in smectite content and crystallinity in sediments from CRP-3, Victoria Land Basin, Antarctica. Terra Antartica, 8(4), 533-542 ...