地质论评2025，Vol.71Issue(4)：1081-1098,18.DOI:10.16509/j.georeview.2024.12.012
淮南张集煤矿石炭系铝质泥岩的沉积环境及成因分析
Sedimentary environment and genetic analysis of Carboniferous aluminous argillites in Zhangji coal mine,Huainan
摘要
Abstract
Objectives:Huainan is located on the southern margin of the North China Craton,where developed aluminous argillites in the Carboniferous Benxi Formation.At the same time,there are thicker aluminous layers in the western Henan area,which is located on the southern margin of the North China Craton.By exploring the differences in mineralization between the two regions,it can provide a better scientific basis for the exploration of bauxite. Methods:This article has conducted X-ray diffraction(XRD),major and trace element analysis,and zircon U-Pb dating tests on the Benxi Formation aluminous argillites in Zhangji coal mine,Huainan,analyzing its geochemical characteristics and genesis,and comparing it with the formation conditions of bauxite in western Henan. Results:Detrital zircon U-Pb dating data show that the peak ages are mainly concentrated in～311.5 Ma,～451.5 Ma,～925.7 Ma,～1753 Ma and～2488 Ma.Compared with the peak ages of zircon in the provenance,it is revealed that the provenances of aluminous argillites are mainly igneous rocks in the North Qinling orogenic belt and metamorphic rocks and igneous rocks in the basement of the North China Craton.In geochemical analysis,Li element is obviously enriched;The range of Sr/Cu is 3.51～45.8,and the range of B/Ga is 13.8～27.9;The Sr/Ba range was1.76～19.6 and the V/(V+Ni)range was 0.76～0.92;Geochemical indicators show that aluminous argillites was formed in arid tropical climate and deposited in marine reductive environment. Conclusions:By comparing the genesis of aluminum argillites in Zhangji coal mine in Huainan and bauxite in western Henan,it is concluded that the metallogenic differences between the two regions are mainly caused by climate and transgression events.Less precipitation and transgression raise the groundwater level,resulting in the deposition of aluminum argillites in an environment with weak leaching and stagnant water,which leads to the lack of further enrichment of Al element and failure to mineralization.Under this condition,Li element is enriched in clay minerals in aluminum argillites.Therefore,bauxite is more likely to develop in areas less affected by marine transgression.According to the distribution of paleosedimentary environment in Huainan area in Benxi period,the metallogenic prospect of bauxite in Huainan area is mainly developed in tidal flat and delta sedimentary environment in the West and north of the study area.At the same time,Li element is relatively enriched in the associated elements of aluminous argillites,which has a certain metallogenic potential.关键词
铝质泥岩/铝土矿/本溪组/地球化学特征/碎屑锆石年龄/物质来源/沉积环境Key words
aluminous argillites/bauxite/Benxi Formation/geochemical characteristics/detrital zircon age/material source/sedimentary environment引用本文复制引用
吕大炜,刘小龙,李泽宽,沈晓丽,张之辉,刘海燕,王洛静,张奥聪,李庆,吴盾..淮南张集煤矿石炭系铝质泥岩的沉积环境及成因分析[J].地质论评,2025,71(4):1081-1098,18.基金项目
本文为国家重点研发计划课题(编号:2022YFC2903402)的成果. This paper was supported by the National Key Research and Development Program(No.2022YFC2903402) （编号:2022YFC2903402）
