滇东黔西地区陆相二叠—三叠系界线粘土岩特征

Characteristics of claystone at the continental Permian-Triassic boundary in the eastern Yunnan-western Guizhou region

摘要: 提要：在滇东黔西地区，海相和陆相二叠—三叠系界线附近均有界线粘土岩存在。本文介绍了该区陆相界线粘土岩的特征，并探讨了其成因。这些粘土岩主要矿物成分为伊／蒙混层矿物（20％～80％）和高岭石（35％～80％），碎屑物中有锆石、磷灰石、六方双锥石英、其他类型石英和微球粒等。提出界线粘土岩中的物质主要是火山成因，也有正常沉积物的加入，可能还拌有撞击作用的影响。

Abstract: Abstract: There exists boundary claystone near the boundary between both the marine and terrestrial Permian and Triassic in the eastern Yunnan-western Guizhou area. This paper introduces the characteristics of the boundary terrestrial claystone in the area and discusses its origin. The principal minerals of the claystone are illite-montmorillonite mixed-layer minerals (20% -80%) and kaolinite (35% -80%), and the fragments include zircon, apatite, hexagonal dipyramidal high-temperature quartz and other types of quartz The And microspherules. It is suggested that the terrestrial boundary claystone in the area mainly formed by volcanism, accompanied by normal deposition and influence of impact.