河南省中寒武世岩相古地理

The Middle Cambrian lithofacies palaeogeography in Henan Province

应用冯增昭教授倡导的"单因素分析多因素综合作图法",对河南省中寒武世以期为单位编制岩相古地理图,探讨海陆分布状况及其演化规律。在毛庄期,华北台地西南部有熊耳陆,台地呈现为泥坪和坪间局限海。泥坪为豫鲁皖泥坪,局限海为晋豫局限海东南部,其中散布有1个准滩、2个雏滩。徐庄期熊耳陆变化不大,华北台地发生分化。豫鲁皖泥坪范围缩小为狭长的晋豫皖泥坪,晋豫局限海向东南扩展成为豫鲁皖局限海,其中分布有3个准滩和5个雏滩。熊耳陆西侧则成为豫陕局限海,发育1个雏滩。到张夏期,熊耳陆逐渐缩小,华北台地泥坪几乎消失,全部变为华北陆表海,为广阔的碳酸盐岩台地,鲕粒滩广布,共发育8个滩、2个准滩、3个雏滩。从毛庄期到张夏期,熊耳陆由扩大变缩小,华北台地泥坪面积逐渐萎缩,而局限海由西北向东南、再向西、向南逐渐扩展,最终占领全部海域。

This paper adopts the ＂ Single factor analysis and multifactor comprehensive mapping method＂ proposed by professor Feng Zengzhao, and compiles the lithofacies paleogeographical maps taking the Age as the mapping unit of the Middle Cambrian of Henan, and approaches the distributive conditions of the sea and land and their evolutionary pattern. During the Maozhuang Age, there was the Xiong＇er Land in the southwest part of the North China Platform, the platform appeared as the mud fiat and inter-fiat restricted sea. The mud fiat was Yu-Lu-Wan （an abbreviation of Henan, Shandong and Anhui Prov-inces） Mud Flat and while the inter-fiat restricted sea was the southeastern part of Jin-Yu （an abbrevia-tion of Shanxi and Henan Provinces） Restricted Sea, in which one penebank and two embryo banks were scattered. During the Xuzhuang Age, no obvious changes occurred on the Xiong＇er Land, but the North China Platform was differentiated. The Yu-Lu-Wan Mud Flat reduced in area to be a narrow and long Jin- Yu-Wan Mud Flat, and the Jin-Yu Restricted Sea extended southeastward, becoming the Yu-Lu-Wan Re- stricted Sea, where three penebanks and five embryo banks were distributed. To the west side of the Xiong＇er Land, the mud flat changed to be the margin of Yu-Shaan （Shaan is the abbreviation of Shaanxi Province） Restricted Sea, where an embryo bank were occurred. Up to the Zhangxia Age, the Xiong＇er Land was reduced in area gradually, at the same time in the North China Platform, the mud flats nearly disappeared, and the whole marine area became the united North China Continental Sea, and to be vast carbonate platform in which the oolitic banks were widely distributed, including eight banks, two pene- banks and three embryo banks. From the Maozhuang Age to the Zhangxia Age, in the North China Pat- form the gradual spreading and reducing of the Xiong＇er Land was associated with the area of the mud flats gradually reducing, while the restricted sea spreaded southeastward firstly and then westward and south- ward, and finally occupied the whole sea area.