An overview of Ordovician and Silurian K-bentonites
HU Yan-hua1,3, LIU Jian1,3, ZHOU Ming-zhong4, WANG Fang-yue1,3, DING Xing1,3, LING Ming-xing1,3 and SUN Wei-dong1,2 1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China;2. School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China;3. Graduate University of Chinese Academy of Sciences, Beijing 100049, China;4. College of Geography and Environment Science, Guizhou Normal University, Guiyang 550002, China
Comparing with Europe and North America, much less attention has been paid on K-bentonite in China. This paper gives an overview on this kind of rock, including its definition, criterion, recent advances and significance, aiming at better understanding and more application of K-bentonites. This papaer also introduces Ordovician K-bentonites of South China and suggests three research directions on this basis. The first is the relationship between volcanic activity represented by K-bentonite and mass extinction in Late Ordovician; the second is comparing South China with other regions using melt inclusions in minerals from K-bentonites; the last is carrying a high-precision geochronology study about Ordovician K-bentonites in South China. In a word, as a special event-stratigraphic marker, it has important research value in chronostratigraphy, event stratigrapy, reconstruction of paleocontinents, and stratigraphy correlation, it will play an important role in paleoenvironment, paleotectonic, paleogeographic research.