新疆哈密晚石炭世企鹅山组火山碎屑与碳酸盐混合沉积  

MIXED PYROCLASTIC-CARBONATE SEDIMENTS IN THE LATE CARBONIFEROUS QI’ESHAN FORMATION FROM HAMI AREA,XINJIANG,NW CHINA

作　　者：高璐[1] 张雄华[1] 李浩[1] 张孟 李黎[1] 周寅生 GAO Lu;ZHANG Xiong-hua;LI Hao;ZHANG Meng;LI Li;ZHOU Yin-sheng(China University of Geosciences,Wuhan 430074)

机构地区：[1]中国地质大学(武汉),湖北武汉430074

出　　处：《地层学杂志》2020年第4期401-410,共10页Journal of Stratigraphy

基　　金：新疆卡拉塔格一带丹乔喀幅等12幅戈壁荒漠覆盖区地质填图项目(DD20179607)资助。

摘　　要：新疆哈密库木塔格沙垄地区上石炭统企鹅山组发育多套含藻礁的碳酸盐岩沉积,该碳酸盐岩沉积及邻近层位均出现多套火山碎屑和碳酸盐的混合沉积。目前,火山碎屑-碳酸盐混合沉积的研究鲜有报道,该类岩石类型的分类命名也尚无讨论。本文旨在通过分析该类岩石的野外分布状态、矿物组成及岩石地球化学特征等,讨论该类岩石的分类命名,并进一步探讨其成因。研究表明:研究区内企鹅山组的火山碎屑-碳酸盐混合沉积主要为同一岩层内火山碎屑组分和碳酸盐组分混合沉积,在岩性上表现为碳酸盐质-火山碎屑混积岩、含火山碎屑-碳酸盐混积岩、火山碎屑质-碳酸盐混积岩等。就成因而言,该类混合沉积可分为相缘渐变混合沉积、事件突变混合沉积、原地混合沉积。Late Carboniferous reefal limestones are widely exposed in the Qi’eshan Formation from Hami Kumutag Sand-ridge Area,Xinjiang,NW China,and variously mixed pyroclastic-carbonate sediments(MPCS)were discovered from these limestones and its adjacent strata.Previous studies show an immature research level that greatly impacted the classification and nomenclature of MPCS.Systematic investigation involving the distribution of field outcrops,petrological and geochemical characteristics can be used for discussions on the classification,nomenclature and genetic interpretations of MPCS.Our new data suggest that the MPCS in study area is mainly presented in one layer as the mixed deposition of pyroclastic and carbonate components.It can be petrologically classified as carbonate bearing pyroclastic rocks,carbonate pyroclastic rocks,pyroclastic limestones,pyroclastic bearing limestones,etc.While the mixing of pyroclastic and carbonate sediments can be divided:facies transitional deposits,event deposits and autochthonous deposits.

关 键 词：火山碎屑-碳酸盐混合沉积 企鹅山组 晚石炭世 哈密 

分 类 号：P534.45[天文地球—古生物学与地层学]