汤原断陷宝泉岭组微量元素地球化学特征及其对沉积环境的指示意义  

Geochemical Characteristics of Trace Elements and Its Sedimentary Implication in Baoquanling Formation,Tangyuan Fault Depression

作　　者：冀华丽 何中波[1,2] 卫三元 林效宾[1] JI Huali;HE Zhongbo;WEI Sanyuan;LIN Xiaobin(Beijing Research Institute of Uranium Geology,Beijing 100029,China;School of Earth Sciences,East China University of Technology,Nanchang,Jiangxi 330013,China)

机构地区：[1]核工业北京地质研究院,北京100029 [2]东华理工大学地球科学学院,江西南昌330013

出　　处：《世界核地质科学》2022年第1期27-38,共12页World Nuclear Geoscience

基　　金：中国核工业地质局铀矿勘查项目(编号:202006-4);“砂岩型铀矿多重耦合地质成矿作用与时空定位”项目(编号:中核科发(2021) 143号)联合资助

摘　　要：沉积物的地球化学特征在沉积背景分析中起着非常重要的作用。以汤原断陷古近系宝泉岭组沉积时期泥岩和粉砂岩样品中微量元素含量为依据,选用对沉积介质环境反映比较敏感的锶(Sr)、钡(Ba)、铜(Cu)、钒(V)、镍(Ni)、铀(U)等微量元素指标,详细研究了目的层段岩石样品的元素地球化学特征,分析了研究区目标层中微量元素含量及其比值与沉积介质环境之间的对应关系,探讨了汤原断陷古近纪的沉积介质环境。结果表明:泥岩样品中Sr/Ba比值较低,反映陆相淡水环境;Sr/Cu比值较高,表明处于温湿-干热气候;V/(V+Ni)比值偏高,推断处于厌氧还原环境。总体来说,汤原断陷古近系宝泉岭沉积时期沉积环境主要为偏干热气候的陆相淡水还原环境。Geochemistry plays an important role in the analysis of sedimentary background.Trace elements such as Sr,Ba,Cu,U,V,Ni,which are sensitive to the sedimentary environment.Paleogene samples from Tangyuan fault depression were selected to study the geochemical characteri stics.The relationship between Sr/Ba,Sr/Cu,V/V+Ni,Cu/Zn,Th/U ratio and sedimentary environment was discussed based on the results of trace element analysis.The results showed that Sr/Ba ratio is small reflecting the terrestrial fresh water environment,Sr/Cu ratio is higher indicating warm and humid or dry and hot climate,and the higher V/V+Ni ratio referring to anaerobic reduction environment.On the whole,the sedimentary environment of Paleogene Baoquanling Formation in Tangyuan fault depression is mainly terrestrial freshwater reduction environment with dry and hot climate.

关 键 词：微量元素 沉积介质环境 古近系 宝泉岭组 汤原断陷 

分 类 号：P595[天文地球—地球化学]