安徽铜陵及邻区早石炭世沉积古地理  

Sedimentary palaeogeography of the Early Carboniferous in Tongling and its adjacent areas in Anhui Province

作　　者：叶春林[1] 刘家润[1] 王训诚[2] 蒋少涌[1] 

机构地区：[1]南京大学地球科学与工程学院内生金属矿床成矿机制研究国家重点实验室,江苏南京210093 [2]安徽省地质矿产勘探局321地质队,安徽铜陵244033

出　　处：《古地理学报》2010年第4期371-383,共13页Journal of Palaeogeography：Chinese Edition

基　　金：国土资源部安徽省公益性地质调查项目(编号:2007-07);江苏省自然科学基金创新学者攀登项目(编号:BK2008026)资助

摘　　要：依据前人研究结果及实测剖面资料、基于层序地层所获得的沉积古地理的研究结果表明:以安徽铜陵为中心区域的研究区,在早石炭世沉积层序CSQ1沉积时期存在呈北东—南西向延展、包含繁昌—铜陵—贵池在内的剥蚀区——繁贵岛,自CSQ2沉积晚期该岛被海侵海泛分割为铜陵北东的繁岛和南西的贵岛两部分,并存续至CSQ3沉积末期;繁贵岛和繁岛、贵岛两侧以及繁岛与贵岛之间为海相、滨海平原相沉积区,发育有浅海相碳酸盐、混有陆源碎屑的碳酸盐以及滨浅海和滨海平原陆源碎屑沉积,各沉积带主要呈北东—南西向展布。此外在CSQ3沉积晚期还发育有潮坪碳酸盐沉积。随着海平面变化,沉积区扩大,岛区缩小,沉积带类型及其空间位置发生变化和迁移摆动。沉积古地理的变化表明,在CSQ1和CSQ3两沉积时期分别发育同沉积断裂(带),后一期断裂横穿原繁贵岛而导致铜陵地区新生海区形成,构成可能的海底热水喷流沉积成矿的构造与古地理背景。The Early Carboniferous palaeogeography and sediments in Tongling district of middle Anhui is taken as a center area.Researches of sequence stratigraphy were carried out.The research results indicate that there might be an island named Fangui Island including Tongling,Fanchang and Guichi in the period of the CSQ1,which is the lowest one of the three depositional sequences in the Early Carboniferous.From the late period of CSQ2 to the period of CSQ3,the sea water with marine flooding divided the Fangui Island into the Fan Island and the Gui Island separately situated in the northeast and the southwest of Tongling.In epeiric seas,the depositional zones of clastic facies,clastic carbonate facies and carbonate facies with the northeast and southwest extension were successively distributed in both sides of the islands and between the Fan Island and the Gui Island as well,and the depositional zones of floodplain clastic facies and the tidal-flat carbonate facies were distributed in coastal plain around the islands.Moreover,depositional regions expanded with island regions narrowing and the facies zones migrated accompanying changes of sea level in the Early Carboniferous.The changes of sedimentary palaeogeography demonstrate that,in period of CSQ3,the contemporaneous faultings with deposition obviously cut across the Tongling district between the Fan Island and the Gui Island and caused the district to be a part of marine.So the faults and marine may be the background to form the massive sulphide deposits probably with submarine hydrothermal exhalation in the Tongling ore cluster area.

关 键 词：安徽铜陵 早石炭世 沉积古地理 同沉积断裂 层序地层 

分 类 号：P531[天文地球—古生物学与地层学]