Dissolution and analysis of amorphous silica in marine sediments
Links
- More information: Publisher Index Page (via DOI)
- Download citation as: RIS | Dublin Core
Abstract
The analytical estimation of amorphous silica in selected Atlantic and Antarctic Ocean sediments, the U.S.G.S. standard marine mud (MAG-1), A.A.P.G. clays, and samples from cultures of a marine diatom, Hemidiscus, has been examined. Quantitative recovery of sedimentary amorphous silica was achieved by reacting 2 M Na 2 CO 3 with a sample for 4 hours at 90 degrees -100 degrees C; where necessary, aluminum analysis is used to correct for the extraction of non-amorphous silica. Oceanic sediments having an amorphous SiO 2 /clay ratio of 1.0 or more can be analyzed by a single extraction with 2 M Na 2 CO 3 , without correction for non-amorphous additions. Marine sediments having an amorphous SiO 2 /clay ratio of from 1.0 to 0.25 can be corrected for inputs of clay-derived silica using an aluminum determination and an empirical correction factor. Sediments with amorphous SiO 2 /clay ratios of less than 0.25, samples containing non-silica-bearing aluminous materials such as gibbsite, or materials having low absolute levels of amorphous silica require successive leaches to accurately correct for silica inputs from non-amorphous sources. Our values for amorphous silica-rich circum-Antarctic sediments are equal to or greater than literature values, whereas our values for a set of amorphous silica-poor sediments from a transect of the North Atlantic at 11 degrees N, after appropriate correction for silica released from clays, are significantly lower than previous estimates from the same region.
Publication type | Article |
---|---|
Publication Subtype | Journal Article |
Title | Dissolution and analysis of amorphous silica in marine sediments |
Series title | Journal of Sedimentary Petrology |
DOI | 10.1306/212F79AF-2B24-11D7-8648000102C1865D |
Volume | 50 |
Issue | 1 |
Year Published | 1980 |
Language | English |
Publisher | SEPM |
Description | 11 p. |
First page | 215 |
Last page | 225 |
Google Analytic Metrics | Metrics page |