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在江西修水四都镇东岭村发现了一个连续的、出露完好的二叠纪-三叠纪界线地层剖面。在剖面中有一段厚约2.1m 的地层具有指示海平面下降的岩石组构。这段地层的底部为红色的碳酸盐颗粒岩。红色是颗粒表面的红色铁染,成分为褐铁矿,是出露地表风化形成的。这层红色颗粒岩之上有约2.0 m 的去白云石化灰岩,其中保留了原来粉晶白云石的晶形。去白云石化作用是白云岩受淡水影响而发生的,指示海平面下降事件。这段地层之上是厚1m 的颗粒岩和灰泥岩,代表浅水潮下环境。其上是二叠系-三叠系的界线。这段地层之下的地层中生物丰富多样,并且有复(蜒)、钙藻等大绝灭前的生物。这段地层及其以上的地层中生物种类很少,(蜓)、钙藻等已经消失,表明集群绝灭事件开始于这段地层之下,生物大绝灭的发生与海平面下降事件的发生是基本同时的。由此认为,可能是海平面下降有关的环境剧变事件引发了二叠纪末的集群绝灭事件。
A continuous and well-exposed Permian-Triassic stratigraphic section was discovered in Dongling Village, Xiudu Si Du Town, Jiangxi Province. A section of the strata about 2.1 m thick in the section has a rock formation that indicates a drop in sea level. The bottom of this formation is red carbonate granitoids. Red is the iron particles on the surface of the red dye, composition of limonite, is exposed surface weathering. There is about 2.0 m of dolomitic limestone above this red granite, retaining the crystalline form of the original dolomite. De-dolomitization occurs as a result of the influence of freshwater on the dolomites, indicating a decrease in sea level events. Above this formation is a 1 m thick granulite and limestone, representing a shallow tidal environment. It is Permian - Triassic boundary. The strata beneath this formation are rich and diverse creatures, with complex (serpentine), calcium algae and other pre-extinction organisms. There are very few species of organisms in this strata and above strata, ( 蜓), calcium algae, etc. have disappeared, indicating that the extinction event of the cluster began under this strata, the occurrence of biological extinction and the decline of sea level The occurrence is basically the same time. Therefore, it is considered that the environmental catastrophe possibly related to the decline of sea level triggered the extinction of the end of the Permian.