Record Details
Field | Value |
---|---|
Title | Trace element studies of metalliferous sediments in cores from the East Pacific Rise and Bauer Deep, 10⁰ S |
Names |
Kendrick, John William
(creator) Heath, G. Ross (advisor) |
Date Issued | 1973-10-02 (iso8601) |
Note | Graduation date: 1974 |
Abstract | Major (Fe, Mn, Al) and minor (Cr, Mo, Pb, Zn, Cd) element analyses of metalliferous sediments in cores from the East Pacific Rise and Bauer Deep indicate that the Bauer Deep sediments are similar in chemistry and origin to metalliferous sediments of the East Pacific Rises. Fe, Pb, and Zn are strongly associated in both cores and are probably related to the hydrothermal processes which are postulated to occur on the East Pacific Rise. Incomplete Cd data suggest that Cd may also be released during hydrothermal leaching of basalt Mn may originate by precipitation from hydrothermal solutions or by normal authigenic precipitation from sea water. The similar accumulation rates of Mo in both cores, and poor correlation of Mo with Fe imply that Mo is being extracted from sea water. The low abundances of Cr and Al in metalliferous sediments suggest that detritus is a minor component of the sediments. Poorly crystalline smectites constitute a major mineralogical phase of metalliferous sediments. Chemical and mineralogical studies indicate that the smectite is an iron-rich montmorillonite, similar in composition to the bulk sediment. Information on sedimentation rates in the two cores indicate that most elements are accumulating faster on the East Pacific Rise than in the Bauer Deep. Accumulation rates of metals in the Bauer Deep have decreased up to the present and are currently similar to those for normal pelagic sediments. It is inferred that the sedimentation rates in the Bauer Deep are influenced by the proximity of the East Pacific Rise, It appears that sediments in the Bauer Deep are largely the product of hydrothermal processes on the East Pacific Rise, and that the precipitates are transported in suspension to the Bauer Deep. Authigenic precipitation of elements from sea water also occurs, having a stronger influence on the sediments as the precipitation of rise-crest material decreases away from the ridge. |
Genre | Thesis/Dissertation |
Topic | Marine sediments -- Pacific Ocean |
Identifier | http://hdl.handle.net/1957/29284 |