四川广安谢家槽剖面早三叠世地层中的时错相沉积及其古生态意义——一个传统地层剖面的重新解读

EARLY TRIASSIC ANACHRONISTIC SEDIMENTS AT THE XIEJIACAO SECTION OF GUANGAN,SICHUAN PROVINCE AND THEIR PALEOECOLOGICAL SIGNIFICANCES : A RESTUDY OF A CLASSICAL SECTION

四川广安谢家槽剖面下三叠统夜郎组和嘉陵江组中含有扁平砾石灰岩、蠕虫状灰岩、叠层石、层纹状灰岩、薄层泥晶灰岩、条带状灰岩和水平分布的遗迹化石等类型丰富的时错相沉积,由下至上时错相沉积呈现出逐渐减弱的总趋势。早三叠世晚期,时错相沉积从正常海洋环境沉积中退出,只是出现在高压力环境的沉积物中。时错相沉积的这种时空分布和发育程度的变化,反映二叠纪末生物大灭绝事件后,早三叠世海洋生态系复苏的历程。

Various anachronistic sediments such as flat-pebble conglomerates, vermicular limestones, stromatolites, microlaminate limestone, thin-bedded limestone, ribbon limestone, and horizontal trace fossils occur abundantly in the Lower Triassic Yelang and Jialingjiang formations at the Xiejiacao Section of Guangan,Sichuan Province. The relative abundance of these anachronistic sediments decreases section, and they are restricted to the high-stress environments in the late Early Triassic. The temporal and spatial distribution of the anachronistic sediments reflects the recovery history of the ocean and paleoecologic systems following the end-Permian mass extinction.