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通过综合岩相和生物群落特征对贵州罗甸干田坳晚二叠世生物礁进行分析,将研究区划分出三期造礁旋回。对造礁海绵在三个造礁阶段,以及礁前砾屑岩的成分面积进行统计,计算出各阶段的造礁成分组成状况,还原当时的造礁群落。共鉴定出纤维海绵纲3科4属,房室海绵纲9科10属和硬海绵纲2科2属。数据表明自始至终纤维海绵纲的小领针海绵属都为造礁群落里的优势生物,其中S1阶段房室海绵纲的多囊腔海绵属种、叠瓦腔海绵属种和泡腔海绵属种为造礁主体;S2阶段小领针海绵和一纤维海绵未知属种为造礁主体,S3阶段房室海绵的多囊腔海绵占造礁主导地位。统计表明造礁海绵群团的分异度由S1至S3期降低明显。同时着重对本礁点主体的S2阶段骨架礁岩各个部分的结构特征进行细致分析,尤其是RFC的形成历史进行探讨,碳氧同位素测试得到的数据表明S2阶段古水温经历了高达16℃左右的波动,而RFC形成时的古水温为37.86℃,它是一种高温海水的反映;最后通过与南盘江盆地同期的紫云礁和茅口期的广西隆林礁进行对比,揭示它们的成礁模式和演化的异同。
By analyzing the characteristics of lithofacies and biomes, we analyzed the Late Permian bio-reefs in the dryland depression of Luodian, Guizhou Province, and divided the study area into three reef reefs. The reef-making sponges in the three reefs stage, as well as the former reef aggregates of the composition of the area statistics, calculated at each stage of the reef composition of the composition of the state reefs to restore the community. A total of 3 families, 4 genera, 3 families, 9 families, and 2 families, 2 families, were identified. The data showed that all of the genus Phylloscopidae were predominant organisms in the reef-forming communities. Among them, the S1-stage aphid sponges, Reef-forming bodies; S2 stage small-pin sponges and a fibrous sponge unknown species as the reef body, S3 stage atrioventricular sponge multi-cysts sponge dominance. Statistics show that the differentiation of reef-forming sponge groups from S1 to S3 decreased significantly. At the same time, the structural features of various parts of reef skeleton of S2 stage skeleton are analyzed in detail, especially the formation history of RFC. The data obtained from carbon and oxygen isotope test shows that the ancient water temperature in S2 stage fluctuated up to about 16 ℃ , While the ancient water temperature at the time of RFC formation is 37.86 ℃, which is a reflection of high temperature seawater. Finally, by comparing with the reefs of Ziyun Reef in the same period of Nanpanjiang Basin and Longling Reef in Guangxi Zhuang Autonomous Region, The similarities and differences between model and evolution.