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淮南地处中国南方型和北方型震旦系发育的过渡地带,是解决该两套岩系对比和建立中国上前寒武系真正层序问题的关键地区之一。 本文即是笔者等在原工作的基础上,按照国家所下达的研究任务要求,于1977～1979年深入地开展专题研究工作的初步总结。文内简要地论述了在此次工作中的一系列新的发现,如:在华北准地台南缘,首次地发现了早寒武世多门类小壳化石层位;创建了以Chuaridae为主体的晚前寒武纪“淮南生物群”;在淮南一带发现了“凤台砾岩”中的冰筏落石相沉积和两个冰成沉积旋回;在霍邱一带发现了比原震旦纪“霍邱砾岩”层位更低的冰碛砾岩和冰水纹泥沉积层;在凤定地区发现了八公山组与刘老碑组间的假整合关系,并确定了其下伏浅变质岩中有三次火山喷发旋回;测定了有关岩系的同位素年令和较系统地鉴定了微古植物组合等等。在此基础之上,从理论和系实际资料方面,着重地论证了创建“淮南群”和“凤定群”及其内部划分等问题,并讨论了其时代的归属,进而提出了我国南、北方震旦系对比和建立中国上前寒武系层序的新方案。
Huainan lies in the transitional zone of southern China and northern Sinian development. It is one of the key areas for solving the contrast between these two sets of rock series and establishing the true sequence of Precambrian systems in China. This article is the author on the basis of the original work, etc., in accordance with the requirements of the research mission issued by the state, conducted a preliminary summary of the special research work in 1977 ~ 1979. In this paper, a series of new discoveries in this work are briefly discussed. For example, in the southern margin of North China terraces, the early Cambrian small-shelled fossil beds were found for the first time. Chuaridae was the main body Late Precambrian “Huainan biota”; in the Huainan area found “Fengtai conglomerate” in the ice-raft sedimentary deposition and two ice into sedimentary cycles; found in the Huoqiu area than the Sinian “Huo Qiu conglomerate ”lower glacial conglomerate and ice muddy mud sedimentary layer; found in the Fengding area of the Bagoongshan Formation and the Liu Laobei Formation between the fake integration, and to determine the underlying shallow metamorphic rocks There were three volcanic eruption cycles; dating of the isotopes of the rock series and the systematic identification of microphytic assemblages, among others. On this basis, from the aspects of theory and actual data, this paper emphatically demonstrates the problems of creating “Huainan Group” and “Fengding Group” and their internal division, and discusses the ownership of their times, Comparison of Sinian Systems in Northern China and Establishment of a New Scheme of Precambrian Preorders in China.