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华南大隆组硅质岩地层含有大量的、多种类型的硅质海绵骨针,这些骨针为研究二叠纪末硅质海绵动物的灭绝过程和模式提供了丰富的材料.通过对广西东攀和贵州马鞍营剖面海绵骨针的研究,共发现海绵骨针52种类型85亚类型.这些海绵骨针在接近二叠纪和三叠纪(P/T)界线附近分异度迅速降低,88%～90%的类型和88%～92%的亚类型消失,只有5种亚类型延续到了早三叠世,包括Oxeas A,Oxeas B,Strongles B,Oxy-orthpentactines和Oxy-orthohexactines A.不同轴数骨针类型的灭绝顺序不同:三轴和四轴骨针最先消失,然后是多轴和网状骨针消失,单轴骨针消失偏晚.不同表面结构特征的海绵骨针灭绝顺序也不同:分枝型和多刺型骨针较早灭绝,光滑型的骨针较晚灭绝或延续到了下三叠统地层中.其灭绝过程表现为逐渐的灭绝模式,并且可以分为两个灭绝阶段:第一阶段呈现出较慢的灭绝速度和较低灭绝率,第二阶段灭绝速度和灭绝率急剧升高.
The silicalite strata in the Dalong Formation in South China contain a large number of various types of siliceous sponge spicules, which provide abundant materials for studying the extinction process and mode of Late Permian siliceous sponges. Pan and Guizhou saddle camp sponge spicules study found a total of 52 types of sponge spicules 85 subtype types of these sponge spicules near the Permian and Triassic (P / T) near the boundaries of the rapid decline in the degree of differentiation, 88% to 90% of the 88% to 92% of the subtypes disappear and only 5 subtypes have disappeared into the Early Triassic, including Oxeas A, Oxeas B, Strongles B, Oxy-orthpentactines and Oxy-orthohexactines A. No The extinction order of the concentric spicules is different: the three-axis and four-axis spicules disappear first, then the multi-axis and reticular spicules disappear, and the uniaxial spicules disappear late.The sponge spicules with different surface features are extinct The order is also different: the branched and prickly-shaped spicules were earlier extinct, and the smooth-shaped spicules were later extinct or extended into the Lower Triassic strata.The extinction process showed a gradual extinction pattern and could be divided into two Extinction phase: The first phase showed a slower rate of extinction and lower extinction Rate, a sharp increase in extinction rate and the second phase of extinction rates.