Conversion of Smectite to Chlorite by Hydrothermal and Diagenetic Alterations, Hokuroku Kuroko Mineralization Area, Northeast Japan
Atsuyuki Inoue, 1985. "Conversion of Smectite to Chlorite by Hydrothermal and Diagenetic Alterations, Hokuroku Kuroko Mineralization Area, Northeast Japan", Proceedings of the International Clay Conference Denver, 1985, Leonard G. Schultz, H. van Olphen, Frederick A. Mumpton
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The conversion of trioctahedral smectite to chlorite has been examined using drill core samples from the Hokuroku Kuroko mineralization area of Japan, where silicic pyroclastic rocks have undergone intensive hydrothermal and diagenetic alterations. The percentage of expandable layers in trioctahedral chlorite/smectite (C/S) decreases discontinuously with depth, with steps at 100–80%, 50–40%, and 15– 0%; thus the C/S exhibits a trimodal frequency in expandability throughout a given drill hole. These three types of C/S, having expandabilities of about 80%, 50% (corrensite), and 15%, coexist over a depth range of about 200 m. This discontinuous change in expandability contrasts with the continuous change from 100 to 0% expandability found for illite/smectite. As smectite converts to chlorite, C/S increases in tetrahedral Al, octahedral Fe, and exchangeable Mg and Fe and decreases in tetrahedral Si and exchangeable Na and K.
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Proceedings of the International Clay Conference Denver, 1985
The papers included in this proceedings volume are representative of the research on clays being conducted in all parts of the world at the time of publication. Many of the subjects treated are controversial, and although some ideas expressed may not necessarily represent the views of the editors, the referees, or the publisher, they deserve to be brought to the attention of the international clay community.