Restudy of the Permian-Triassic boundary clay in Meishan, Changxing, Zhejiang, China
Titel:
Restudy of the Permian-Triassic boundary clay in Meishan, Changxing, Zhejiang, China
Auteur:
Jinwen, He
Verschenen in:
Historical biology
Paginering:
Jaargang 2 (1989) nr. 1 pagina's 73-87
Jaar:
1989
Inhoud:
The Permian-Triassic boundary clay in Meishan of Changxing. Zhejiang, China, is a thin, extremely fine grained clay, consisting of over 95% of randomly interstratified illite-smectite and minor amounts of kaolinitc, hexagonal dipyramidal quartz, zircon, apatite, pyrite and microspherules. It contains abundant marine fossils with a distinct aspect of latest Permian. The randomly interstratified illite-smectite was the product of marine diagenesis. Based on the studies of the clay minerals, detrital minerals, elemental geochemical characters and marine fossils, it is concluded that the boundary clay was formed in a slightly reducing low energy environment with quiet and stagnant water and is late Late Permian in age. The Permian-Triassic boundary should be placed at the top of the boundary clay.