运城盐湖形成演化与盐离子来源  

Formation and evolution of the Yuncheng Salt Lake and sources of the saline ions

作　　者：寇琳琳 李振宏[1,3,4] 夏彩香 韦利杰 董晓朋[1,3,4] 王森 崔加伟[1,3,4] 黄婷 南德斌 KOU Linlin;LI Zhenhong;XIA Caixiang;WEI Lijie;DONG Xiaopeng;WANG Sen;CUI Jiawei;HUANG Ting;NAN Debin(Institute of Geomechanics,Chinese Academy of Geological Sciences,Beijing 100081,China;School of Earth Sciences,China University of Geosciences(Wuhan),Wuhan 430074,Hubei,China;Key Laboratory of Paleomagnetism and Tectonic Reconstruction,Ministry of Natural Resources,Beijing 100081,China;Key Laboratory of Active Tectonics and Geological Safety,Ministry of Natural Resources,Beijing 100081,China;Yunnan Geological Survey Institute,Kunming 650216,Yunnan,China)

机构地区：[1]中国地质科学院地质力学研究所,北京100081 [2]中国地质大学(武汉)地球科学学院,湖北武汉430074 [3]自然资源部古地磁与古构造重建重点实验室,北京100081 [4]自然资源部活动构造与地质安全重点实验室,北京100081 [5]云南省地质调查院,云南昆明650216

出　　处：《地质力学学报》2024年第6期933-951,共19页Journal of Geomechanics

基　　金：中国地质调查局地质调查项目(DD20221644,DD20190018);国家自然科学基金项目(41972119,41702216)。

摘　　要：运城盐湖位于汾渭地堑系的核心部位,是中国乃至世界上开发较早的盐湖,但对其基础地质背景的研究却相对薄弱,缺乏统一的认识。文章聚焦新生代地貌巨变过程与汾渭地堑系形成、黄河贯通三门峡峡谷东流入海与三门古湖消亡、汾河改道退出运城盆地与运城盐湖形成以及中条山北缘断裂持续活动形成山前凹陷4个主要阶段,探讨运城盐湖的形成演化过程,并结合区域上重点层位的地球化学元素分析,探讨盐湖盐类物质的主要来源。研究结果显示,古近纪至新近纪中新世中期,中国大陆东部的滨太平洋构造域和西部的青藏高原构造域共同开启了运城盐湖演化的序幕;距今约70万年的早-中更新世,黄河贯通三门峡峡谷东流入海,三门古湖消亡,运城盐湖的雏形开始形成;距今约7万年的晚更新世中期,汾河发生改道退出运城盆地,运城盐湖由开放体系进入封闭体系,运城盐湖最终形成;随后在中条山北缘断裂的持续活动作用下,形成了一个大面积的沉积洼地,大量的含盐类矿物质在这里汇集,经过长期的沉淀蒸发,最终形成了天然盐湖;运城盐湖的盐类物质主要来源于深部成矿盐层,控制盐湖的主要断裂提供了盐类物质的主要通道,中条山北缘中元古界蓟县系龙家园组海相高镁白云岩提供了镁离子来源。研究成果将为运城的生态保护与合理开发提供基础地质依据。[Objective]Yuncheng Salt Lake,located within the core area of the Fenwei Graben System in the south-central part of the North China Craton,is the earliest known salt lake in China and worldwide.The formation and evolution of the Yuncheng Salt Lake are closely related to the Cenozoic tectonic domains of the coastal Pacific in eastern China and the Qinghai-Tibet Plateau in western China.However,there are many debates regarding the spatiotemporal processes and key timing associated with these two domains in the Yuncheng Salt Lake.Additionally,the salt lake is rich in sodium,magnesium,chloride,and sulfate ions;however the sources of these saline ions remain unclear.[Methods]This study investigated the major changes in the Cenozoic tectonic geomorphology of the Yuncheng Basin and its surrounding areas,focusing on the evolution of the Cenozoic river-lake system to establish the formation and evolution stages of the Yuncheng Salt Lake.This study combined the tectonic background and geochemical element analysis of typical strata in the adjacent Zhongtiao Mountains to identify the main sources of saline ions in the Yuncheng Salt Lake.[Results]At the boundary between the Paleogene and Neogene,there was a widespread angular unconformity across the central and eastern parts of the North China Craton.This unconformity affected the Weihe Basin in the Fenwei Graben System to the west,and not the northeastern edge of the Qinghai-Tibet Plateau,which connects to the western North China Craton.This indicates that the tectonic forces during this period originated mainly from the coastal Pacific tectonic domain of the eastern North China Craton.In the mid-Miocene,a widespread unconformity along the northeastern edge of the Qinghai-Tibet Plateau connect to the western North China Craton.The northeastward uplift and expansion of the Qinghai-Tibet Plateau affected caused the Ordos Basin to rotate counterclockwise,initiating the formation of the Shanxi Graben System within the Fenwei Graben System.The Cenozoic evolution of the Yuncheng S

关 键 词：地球化学元素 盐离子 三门古湖 汾河改道 运城盐湖 新生代 湖泊地貌 

分 类 号：P931[天文地球—自然地理学] P595