中国三大陆块中—新元古代泥质岩与碳酸盐岩元素地球化学特征  

Element geochemistry characteristics of Meso-Neoproterozoic argillaceous and carbonate rocks in three continental blocks of China

作　　者：刘东娜[1,2] 赵爽 赵峰华 旷红伟[3] 邹雨[4] 张继彪 程晨 LIU Dongna;ZHAO Shuang;ZHAO Fenghua;KUANG Hongwei;ZOU Yu;ZHANG Jibiao;CHENG Chen(Taiyuan University of Technology,Taiyuan,Shanxi 030024,China;China University of Mining and Technology,Beijing 100083,China;Institute of Geology,Chinese Academic of Geological Sciences,Beijing 100037,China;Wuxi Research Institute of Petroleum Geology,SINOPEC Petroleum Exploration&Production Research Institute,Wuxi,Jiangsu 214126,China)

机构地区：[1]太原理工大学,山西太原030024 [2]中国矿业大学(北京),北京100083 [3]中国地质科学院地质研究所,北京100037 [4]中国石化石油勘探开发研究院无锡石油地质研究所,江苏无锡214126

出　　处：《地质学报》2023年第12期4052-4066,共15页Acta Geologica Sinica

基　　金：国家重点研发计划深地资源勘查开采重点专项课题项目(编号2016YFC0601001);山西省自然科学基金项目(编号202203021221077)联合资助的成果。

摘　　要：中国三大陆块中—新元古代地层格架中广泛分布低变质程度的泥质岩与碳酸盐岩,其元素地球化学特征为研究地表圈层的历史演化提供了重要的基础资料。本文收集了近十几年国内外已发表的近2000组泥质岩/碳酸盐岩中地球化学数据,包括40种常量、微量元素含量组成,涉及华北陆块长城系、蓟县系、待建系及青白口系,扬子和塔里木陆块南华系、震旦系。结合文献中样品的岩性、实验方法以及地质背景特征,主要得出了以下认识:①泥质岩中常量元素的平均含量与中国东部未变质泥质岩中的相似,但其整体上受到了新元古代冰期的影响,化学风化作用较弱,易流失的Na、K及Ca元素含量相对较高;碳酸盐岩中的常量元素含量组成与中国东部未变质富泥碳酸盐岩对比,具有少量的陆源物质输入且以白云岩为主,Mg含量较高。②碳酸盐岩中较高的Mn/Sr比值应与成岩蚀变作用有关,虽然硅酸盐矿物少于泥质岩,但Sc、REE+Y以及氧化还原敏感元素更加富集,Sc和REE+Y元素与陆源碎屑的混染作用有关,而后者与氧化的海洋环境有关。③中元古代早期,华北沉积物中记录了Ce元素负异常以及氧化还原敏感元素含量的增高,响应了一次浅海的氧化事件,并促使了生物的演化。④进入新元古代,“雪球地球”事件被塔里木陆块泥质岩大范围变化的化学蚀变指数所记录,伴随着间冰期及冰期后海洋的增氧,扬子陆块新元古代沉积物部分微量元素含量又一次增加,对应着伊迪卡拉生物群的出现。Low metamorphic argillaceous rocks and carbonate rocks are widely distributed in the Meso-Neoproterozoic stratigraphic framework of the three continental blocks in China.Its geochemistry characteristics of elements provide important basic data for us to study the history evolution of the lithosphere.In this paper,we collected nearly 2000 sets of geochemistry data in argillaceous rocks/carbonate rocks that have been published in China and abroad in the past decade,including 40 major and trace element content compositions,involving the Changcheng System,Jixian System,Undefined System and Qingbaikou System of the North China block,the Nanhua System and the Sinian System of the Yangtze and Tarim blocks.In combination with the lithology,experimental methods and geological background characteristics of the samples in the literature,we mainly draw the following conclusions:①The average content of major elements in argillaceous rocks is similar to that in unmetamorphosed pelite in eastern China.But it was influenced overall by the Neoproterozoic ice age and has a relatively high content of Na,K and Ca elements that are easily lost by chemical weathering.The content composition of major elements in carbonate rocks can be compared with that of unmetamorphosed mud-rich carbonate rocks in eastern China.There is a small amount of terrigenous detrital input,mainly dolomite,and the Mg content is high.②The high Mn/Sr ratio in carbonate rocks should be related to diagenetic alteration.Although silicate minerals in carbonate rocks are less than those in argillaceous rocks,Sc,REE+Y and redox sensitive elements are more enriched.Sc and REE+Y elements are related to the hybridization of terrigenous clasts,and the latter is related to the oxidized marine environment.③In the early Mesoproterozoic,the negative anomaly of Ce element and the increase of redox sensitive element content were recorded in the sediments of North China,which responded to a shallow sea oxidation event and promoted the biological evolution.④In the Neoprot

关 键 词：中—新元古代 泥质岩 碳酸盐岩 元素 地球化学 

分 类 号：P534.3[天文地球—古生物学与地层学] P588.2[天文地球—地质学] P595