Hydrogen, oxygen and carbon isotope geochemistry of palygorskite clay deposits in Jiangsu and Anhui Provinces, China

摘要

The palygorskite clay mineralization belt in Jiangsu and Anhui Provinces is an important mineral district in China. According to its geological characteristics, mineral assemblages and hydrogen, oxygen and carbon isotope geochemistry,the palygorskite clay deposits were formed in an arid-semiarid climate. The hydrogen and oxygen isotopic compositions of palygorskite and smectite are not same as those of hydrothermal clay minerals.These isotopic compositions indicate that there is a genesis relationship among the palygorskite clay deposit and the evaporation conditions and the isotopic composition characteristics of the regional paleo- meteoric water. The carbon and oxygen isotopic compositions suggest that the palygorskite clay deposits were formed in continental fresh lakes.