山形県出羽丘陵の青沢玄武岩中に産するクロライト/スメクタイト混合層鉱物

概要

論文の詳細を見る
Smectite and various interstratified chlorite/smectite (C/S) are widely distributed in the Miocene basicvolcaniclastic sediments of the Green Tuff Formation (Aosawa basalts) in the Dewa Hill, YamagataPrefecture. These clay minerals have been investigated by X-ray, chemical and thermal analyses as well asmicroscopic observation. Transformation process from smectite to interstratified C/S is explained as follows. At first, Mg-richsmectite had been deposited from pore solution which contains dissolved substances as a result of reaction ofinterstitial seawater with basaltic glass. In the second stage, by increasing temperature, the smectite hadtransformed to randomly interstratified C/S (chlorite layer < 33%), that is fine-grained and low interferencecolored crystal. Finally, regularly interstratified C/S (corrensite) had been produced by recrystallization.Transition from smectite to corrensite in the Aosawa basalts is not continuous: it is characterized bydiscontinuous stepwise change between C/S (chlorite layer < 33%) and corrensite (chlorite layer 40-50%).
日本粘土学会の論文
1999-06-30