关键词: 关岭动物群, 上三叠统, 瓦窑组, 爬行动物化石层, 埋藏环境

Abstract: Petrological samples collected from the Upper Triassic Wayao Formation bearing t he Guanling Fauna,located in Xinpu area of Guanling County, Guizhou rovince, were observated under microscope. Three kinds of lithology can be distinguished on the basis of the bio-abundance. Considering the bio-assemblage of the Guanling Fauna, its taphonomic environment characteristics can be concluded as follows: the sea water was relatively deep, lower energy, peachful and anoxic condition with normal paleosalinity and warmer climate. In addition, the distributions of the conodontParagondolella and the bivalve Halobia confirm the taphonomic environment and indicate the occurrence of the anoxic event as well. The study of paleoredox markers and fossil diversity finds two main significant factors. One is the fine grain and compact texture of marly lime stone bearing the Guling Fauna, which makes the remains deposit nearly intact. The other is the layer of reptile and crinoid fossils coincide well with w(Ce)/w(La) value over 2.0 and increasing positively, which reveals a high anoxic condition just like a protecting cover which keep the remains out of the oxygen.

Key words: Guanling Fauna, Upper Triassic, Wayao Formation, layer of reptile fossils, taphonomic environment