江西信江盆地石溪组生物群及其时代

The Shixi Formation in the Xinjiang Basin of Jiangxi and its biota and age

石溪组以不整合覆盖在鹅湖岭组之上，其上为周家店组所覆盖的中生代火山岩地层上部。近年来，在石溪组中发现大量昆虫化石。对正确划分对比中国南北方陆相中生代地层有重要意义。根据发现的丰富化石及同位素年龄资料，石溪组应属早白垩世早期，但不排除该组下部有部分属晚侏罗世晚期。

The Shixi Formation which rests unconformably on the Ehulin Formation and is unconformably overlain by the Zhoujiadian Formation is the upper part of the Mesozoic volcanic-sedimentary strata. In recent years, a large number of fossil gastropods have been collected from the Shixi Formation in the Shixi region by the authors for the first time. Based on the fossils and isotopic age dating from the middle-upper part of the Shixi Formation in the Shixi region, the biota and its age of the Shixi Formation are discussed in the present paper. The geological age of the Shixi Formation may be early Early Cretaceous, but the possibility can't be ruled out that the lower part of the Shixi Formation belongs to the late Upper Jurassic.