西秦岭北缘漳县含盐盆地成盐阶段构造演化及找矿意义  

Evolution and Prospecting Significance of Zhangxian Salt-Bearing Basin in the Northern Margin of Western Qinling

作　　者：杨永 胡晓隆 林小兵[3] Yang Yong;Hu Xiaolong;Lin Xiaobing(First Institute of Geology and Mineral Exploration,Bureau of Geology and Mineral Exploration and Development of Gansu Province,Tianshui,Gansu,741020,China;Gansu Bureau of Geology and Mineral Exploration and Development,Lanzhou,Gansu,730000,China;State Key Laboratory of Reservoir Geology and Development Engineering,Chengdu University ofTechnology,Chengdu,Sichuan,610059,China)

机构地区：[1]甘肃省地质矿产勘查开发局第一地质矿产勘查院,甘肃天水741020 [2]甘肃省地质矿产勘查开发局,甘肃兰州730000 [3]成都理工大学油气藏地质及开发工程国家重点实验室,四川成都610059

出　　处：《新疆地质》2024年第3期372-378,共7页Xinjiang Geology

基　　金：甘肃省国土资源厅地质勘查基金甘肃省漳县盐矿资源普查项目(甘国土资勘发[2011]37号)资助。

摘　　要：西秦岭北缘漳县含盐盆地是研究青藏高原隆升及演化的重要部位。该盆地的形成是喜山期以来青藏高原隆升在远端构造运动响应的结果,属内陆湖泊伸展断陷盆地。前人对盆山演化与成矿的关系研究欠缺,本次结合最新盐矿勘查成果资料,遵循盆山耦合的研究思路,对该盆地结构特征进行分解,建立盆地构造格架,重塑盆地构造演化过程及盐矿沉积阶段。研究表明:白垩系及更老地层构成了盆地的老基底,盆地成盐阶段构造演化总体分3个阶段:①初始断陷阶段。古近纪始新世至渐新世末期,漳县一带发生近NS向张裂作用,在漳县北部沉积大面积古近系粗-细碎屑岩,奠定了盆地新基底;②强烈断陷阶段。中新世,伸展活动不断增强,在盆地内沉积了一套厚度超过1600 m的含盐泥岩地层;③走滑闭合阶段。上新世早期,伸展活动明显减弱,盆地主要受NS向挤压,老构造断裂发生由张性到压扭、走滑性质的转变,漳县含盐盆地持续演化就位形成现今构造样式。Combined with the latest salt exploration results data of Zhangxian salt-bearing basin,Following the research idea of basin-mountain coupling,research on the relationship between basin-mountain evolution and mineralization.Zhangxian salt-bearing basin is an inland lake extension fault basin that belongs to the north margin of West Qinling Mountains which is an important part to study the uplift and evolution of the Qinghai-Tibet Plateau.It has important guiding significance for prospecting to comprehensive analysis and study of the tectonic evolution.By decomposing and describing the structural characteristics of the basin,the tectonic framework of the basin is established,and the tectonic evolution process and salt deposit stage of the basin are reshaped.The Basin evolution is generally divided into three stages:The first stage in the Paleogene Eocene to Oligocene North China tectonic period,A large area of Paleogene coarse-fine clastic rocks was deposited in the northern part of Zhangxian County,which laid a new base of the basin;The second stage,In the Miocene,a set of thick salt-bearing mudstone strata was deposited in the basin;The third stage,With the continuous development of the Himalayan Movement,the north-south compressive force of the Zhangxian salt-bearing basin was far greater than the east-west compressive force,and the basin began to close in the Neogene Pliocene.The continuous evolution of the salt-bearing basin in Zhangxian County is the result of the revival of old structural faults and the transformation from tension to compression and torsion.

关 键 词：西秦岭北缘 漳县含盐盆地 结构特征 构造演化 找矿意义 

分 类 号：P542[天文地球—构造地质学] P311[天文地球—地质学]