新疆额敏东部志留纪化石的发现及其地质意义

在额敏东部原划为晚泥盆世塔尔巴哈台组的火山碎屑岩夹碳酸盐岩地层中发现了丰富的志留纪文洛克世动物化石, 包括珊瑚Halysites hoboksarensis、H. sp.、Mesofavosites sp., 腕足动物Atrypa sp.、Eospirifer radiatus, 三叶虫Encrinuroides sp.、Encrinurus sp.1、E. sp.2、Cheirurus sp.、Sthenarocalymene sp., 短剑类Lepidocoleus sp.和层孔虫等, 通过区域岩性组合对比, 将该套地层改划为文洛克统沙尔布尔组.珊瑚和层孔虫等对环境要求较高的生物化石的发现, 同时结合地层中风暴沉积的粒序层理、包卷层理及火焰构造等相标志, 说明了额敏东部在文洛克世为火山碎屑质的开阔台地相沉积环境, 处于热带、亚热带气候区. 

Discovery of Silurian Fossils and Its Geological Significance in Eastern Emin,Xinjiang of NW China

Abundant Wenlock animal fossils are found in the succession of the volcanoclastic rocks intercalated with limestones which were considered as the Late Devonian Ta'erbahatai Formation, including corals Halysites hoboksarensis, H. sp., Mesofavosites sp., brachiopods Atrypa sp., Eospirifer radiates, trilobites Encrinuroides sp., Encrinurus sp.1, E. sp.2, Cheirurus sp., Sthenarocalymene sp., Machaeridia Lepidocoleus sp., stromatoporoids and so on. Based on lithological association and stratal correlation, the succession is re-assigned to the Wenlock Shaerbuer Formation, where abundant facies indicators were discovered. Main facies indicators include reefoid corals and stromatoporoids, graded bedding, convolute bedding, flame structure and storm deposits. It is concluded that the Wenlock Shaerbuer Formation was formed in the open platform environment with volcanic activities in tropical and subtropical zones.