The Sedimentary Environment of Attapulgite Clay Deposits on the Border of Jiangsu and Anhui Provinces
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摘要: 本文对苏皖沉积型凹凸棒石粘土矿床形成时的沉积环境特征、水介质的ｐＨ值、氧化还原条件、温度及盐度进行了讨论。研究表明凹凸棒石粘土矿床形成于碱性、还原、低盐度的浅水湖相环境。与火山作用有关的热水溶液参与了成矿作用。Abstract: The Sedimentary attapulgite clay deposit on the boder of Jiangsu and Anhui Provinces is an important producing area of attapulgite clay in China. Ore-bearing Series is a set of sedimentary clastic rocks of shallow lake. The sedimentary medium features are as follows: 1) Various attapulgite clays have different pH values, all of them are formed in an alkalic condition; 2) According to the features and Ceanom calculated values of variant clays, the attapulgite clays are formed in a reducing condition, and part of montmorillonite clay is formed in a weak oxido-condition; 3) On the basis of stable isotopic compositions of opal and dolomite, opal-forming temperature is 71℃ 81℃ and dolomite-forming temperature is 29℃ 74℃.These features with other geochemical characteristics infered that the forming temperature of attapulgite clays is higher than the normal sedimentary temperature; 4) MgO/Al 2O 3 Sr/Ba Rb/K ratios of variant attapulgite clays showed that the forming salinity of dolomite attapulgite clay, siliceous attapulgite clay and attapulgite clay is higher than that of montmorillonite clay. To sum up, the study indicated that under the conditions of alkalic, reducing conditions and low salinity of water medium, attapulgite clay deposits could be formed in a shallow lacustrine basin. The hydrothermal solution being related to volcanic action is of certain significance to mineralization of attapulgite clay deposits.
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Key words:
- attapulgite clay /
- sedimentary environment /
- medium condition
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[1] (1) Singer A and Galan E, Eds. Palygorskite- Sepiolite Occurrence. g enesis and uses (Developments in sedimentary37). Elsevier Scientific Publishing Company, 1984.
(2) Weaver C, Clays, M uds, and shales. Elsevier Scientific Publishing Company, 1990.
(3) Millot G. Geolog y of clays. Spring er-verlay, New York, 1970.
(4) 方邺森, 许冀泉, 李立文. 苏皖地区凹凸棒粘土. 南京大学学报 (自然科学版 ), 1990, (1), 15-23.
(5) Yi Facheng, Tian Xu and Yuan Jianqi, et al. The geological characteristics and geneses of attapulgite clay depositson Jiangsu- Anhui bo rder. In :clay Minerals, Their Natural Resources and Uses. Proceedings of workshop WB-1, The 29 th Inter. Geol.Cong ress. Nag oya, Japan, 1992.
(6) 孙永传, 李蕙生. 碎屑沉积相和沉积环境. 地质出版社, 1986.
(7) 刘宝君, 曾永孚. 岩相古地理基础和工作方法. 地质出版社, 1985.
( 8) Church T M and V elde B. Geochemistry and Origin of a deep- sea pacific palygorskite deposit. Chemical Geolog y, 1979, (25): 31-39.
(9) V elde B, Clay minerals. A Physic-chemical explanation of their occurrence (Developments in sedimentary ). Else-vier Scientific Publishing Company ).
(10) 易发成, 李虎杰, 田煦, 郑自立. 苏皖地区凹凸棒石粘土矿床稳定同位素特征及其地质意义. 矿物学报, 1995,15 (2): 242-247.
(11) 张士三, 沉积岩镁铝含量比及其应用. 矿物岩石地球化学通报, 1988, (2): 112-113. -
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