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华北是我国第四系研究的典型地区,很多研究者曾对其作过较为全面的讨论.但过去仅研究陆相地层与生物群,缺乏海相化石与年代地层学控制,致使一些有关地层时代与地层对比问题未获解决.六十年代以来,华北地区第四纪海相层与化石的发现、为进行第四系的研究开辟了新的前景.作者及何炎对华北第四纪有孔虫做了一系列研究.安藏生及本文作者对北京平原第四系磁性地层学、海相微体与超微化石做了研究.1975年与1978年,河北省地质局七队与其它单位对河北第四系作过比较全面的总结.基于上述资料及某些磁性地层学资料,我们有可能探讨华北海、陆相第四系的划分、对比及地层界线问题.一、华北第四纪海相生物地层系统作者将华北约300万年以来的海相第四系与上上新统划分为十个海相化石组合带(以有孔虫为主,见附表.)这十个带均有直接或间接的年代学资料为佐证.各带多有可靠的区域对比资料确定其上、下接触关系,仅有Ⅰ、Ⅱ带的关系尚待进一步澄清.各带的代表性化石皆以它们在我国的首现资料为准.兹扼要分述如下:(一)Ⅰ组合带 代表化石为Ammonia tepida,Evolutononion weiheense,代表剖面
North China is a typical area of Quaternary research in China, and many researchers have made a comprehensive discussion on it.But in the past only the study of continental facies and biota, the lack of marine fossils and stratigraphic control, resulting in some related stratigraphic age Compared with the formation of the problem has not been resolved.Since the sixties, the discovery of Quaternary marine strata and fossils in North China opened up new prospects for the Quaternary research. Author and Yi Yan Quaternary pores A series of studies were conducted by An Qiansheng and the authors of this paper on the study of the magnetic stratigraphy, marine microfacies and ultrafine fossils of the Quaternary in the Beijing Plain.In 1975 and 1978, the Hebei Provincial Bureau of Geological Seventh Team and other units Based on the above data and some magnetic stratigraphic data, it is possible to investigate the division, contrast and stratigraphic boundary of the Quaternary in the North China Sea and continental facies. The author of the marine biostratigraphic system divides Quaternaries and Upper-Neoproterozoic marine systems of about 3 million years in North China into ten marine fossil assemblages (mainly foraminifera, see the attached table) Both have direct or indirect chronology Data are corroborated by the fact that each belt has more reliable regional comparative data to determine the relationship between the upper and lower contacts, and only the relationships between the bands I and II have yet to be clarified. The representative fossils of each belt are based on their first appearance in China as The main points are summarized as follows: (A) Ⅰ combination of representatives of the fossil Ammonia tepida, Evolutononion weiheense, on behalf of the profile