豫北辉卫淇地区寒武纪早期古地理

Palaeogeography of Early Cambrian Period in HuiWeiQi Region, North Henan

豫北地区寒武纪总体为华北陆表海的一部分,而豫北辉(县)卫(辉)淇(县)地区在寒武纪早期发育不同的古地理特点。在1∶5万实测剖面地层学和岩石学研究的基础上,笔者根据地层、沉积构造、基本层序特征等对豫北辉卫淇地区寒武纪早期(辛集期和朱砂洞期)古地理进行了较详细的分析,认为寒武纪辛集沉积期,豫北辉卫淇地区为陆,由于长期的风化剥蚀,形成一或两条河流,包括河床、边滩、天然堤及洪泛平原(可能为河流与海相过渡,也可能为泻湖);寒武纪朱砂洞期,由于振荡式的海侵,形成了陆海并存、沿海为岛和半岛、沿陆为潮坪的古地理格局。

In Cambrian,North Henan was a part of epeiric sea of North China. Hui-Wei-Qi(Huixian county-Weihui county-Qixian county) region in it has different geologic features in the early Cambrian period. Based on the study of stratigraphy, sedimentary structures, basic sequences of the strata in the 1∶50 000 survey,it is suggested that Hui-Wei-Qi region was a land with one or two rivers during the long-time weathering in Xinji period, which included river bed, river bottom, river side embankment and the river plan or the sea-land-cross zone and lagoons. In Zhushadong period of Cambrian, the region formed its paleogeography framework with the co-existing sea and land, the islands and peninsulas along the seaside and the tidal flats along the landside because of the fluctuating seawater encroachment.