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中国北部寒武纪介形虫分布于早晚寒武世。其所在地层的确切时代(期或亚期)以往多未完全确定下来或者还在争论之中。通过分析有关介形虫、三叶虫及小壳化石的组合面貌,并结合岩石地层学特征,文章认为:(1)新疆下寒武统肖尔布拉克组与玉尔吐斯组应合为一组,仍称肖尔布拉克组,时代大致为梅树村期最晚期至沧浪铺期红井哨亚期。其中所见的介形虫基本上均属筇竹寺期。(2)河南淅川等地包括整个下寒武统的水沟口组,自下而上宜分成水沟口组、上集组、小泉沟组和脑子寨组。目前发现的介形虫产子上集组下部(Ichangia—Neocobboldia带),时代为沧浪铺期红井哨亚期晚期;上集组上部可建立Palaeolenus带,时代为沧浪铺期乌龙箐亚期早期。(3)辛集组和雨台山组及其相当地层应统称猴家山组,但应用系指原“猴家山组”下部的一套含磷岩系,原组上部含Megapalaeolenus的一套灰岩及白云岩则应称昌平组。修订后的猴家山组时代为沧浪铺期红井哨亚期晚期。陕西、安徽迄今所见的介形虫即分布于这一时期。(4)辽宁金县所谓“三十里堡阶”实为馒头组的同物异名,其中所产的介形虫Alutella nakamurai的时代因此应为龙王庙期。(5)辽宁本溪的Aluta chiushuensis与瓦房店的A.paiensis和A.paiensis te-nuis曾被认为产于奥陶系底部,实际上其时代前者为晚寒武世凤山期晚期,后两者为凤山期早期。另外,后两者实为Mononotella的同种个体。
Cambodian ostracods are distributed in the early and late Cambrian in northern China. The exact age of the strata to be formed (period or sub-period) has not been fully defined or still under debate. By analyzing the combination of ostracods, trilobites and small shell fossils, combined with the characteristics of lithostratigraphy, the article thinks: (1) The Lower Cambrian Shoalbulak Formation and Yurtuosi Formation should be A group, still known as the Shoal Bulak group, the era is roughly the last period of plum trees to Canglang shop Red Well post-term. The ostracodes seen in this area are basically Qiongzhusi period. (2) Xichuan, Henan and other places, including the entire Lower Cambrian Shuikoukou group, bottom-up should be divided into Shuigoukou group, on the set, the Koizumi groove group and brain Zhai. At present, the Ichangia-Neocobboldia belt is found in the lower part of the epoch-forming epoch, and the epoch is the late stage of the red well whistle in the Canglang bedding. The Palaeolenus belt can be established in the upper part of the Upper Epoch, Early period. (3) The Xinji Formation and Yu-Taishan Formation and their equivalent strata should be collectively referred to as the Houjiashan Formation, but the application refers to a set of phosphorus-bearing rock formations in the lower part of the original “Houjiashan Formation”, a set of limestone and Megapolis Megapalaeolenus Rock should be called Changping group. The revised era of the Monkey Mountain Group for the Canglang shop Red Well postnatal adolescent. The ostracods seen so far in Shaanxi and Anhui are distributed in this period. (4) Liaoning Jin County The so-called “Thirty Fort grades” is actually a synonym for the bread group, in which the age of the ostracod Alutella nakamurai produced should therefore be the Dragon King Temple period. (5) Aluta chiushuensis in Benxi, Liaoning Province and A.paiensis and A.paiensis te-nuis in Wafangdian were considered to be produced at the bottom of the Ordovician. In fact, the former was Late-Cambrian Fengshan Period, and the latter two were Early Fengshan period. In addition, the latter two are actually Mononotella’s kind of individual.