柴达木盆地小梁山—大风山区域深层卤水水化学特征及成因分析

Hydrochemical Characteristics and Origin Analysis of Deep Brine in Xiaoliangshan-Dafengshan Area of Qaidam Basin

柴达木盆地小梁山—大风山区域深层卤水资源丰富,但是目前勘探程度相对较低。为探讨该区域卤水矿产资源情况,在区域地质背景分析的基础上,采用物探测井、地震等手段,对矿区内深层卤水含水层分布进行了解译;对区域水文地质条件进行了研究,包括区域地下水赋存条件与分布规律,地下水类型及含水岩组划分,结果表明矿区内出露一套微胶结的湖泊相地层,内部赋存高矿化度卤水,划分为碎屑岩类裂隙孔隙水、松散岩类孔隙水2种基本类型;对深层卤水矿体及水化学特征进行了分析,自上而下将深层卤水划分为5个矿层,均属硫酸镁亚型卤水。最后,从地形条件、构造特征及气候条件分析了深层卤水钾盐矿资源的沉积演化规律,以期对柴达木盆地的深层卤水资源的深度评价、开发与利用提供基础资料参考。

There are abundant deep brine resources in Xiaoliangshan-Dafengshan area of Qaidam Basin,but the degree of exploration is relatively low at present.In order to explore the status of brine mineral resources in the region,based on the analysis of regional geological background,the distribution of deep brine aquifers in mining area is interpreted by means of geophysical exploration wells and earthquakes,and the regional hydrogeological conditions are studied,including the occurrence conditions and distribution rules of regional groundwater,groundwater types and the division of aquifer rock groups.A set of micro-cemented lacustrine facies strata is exposed in the area,which contains high salinity brine,which can be divided into two basic types:fractured pore water of clastic rocks and pore water of loose rocks.The deep brine orebodies and hydrochemical characteristics are analyzed,and the deep brine is divided into five ore layers from top to bottom,all of which belong to magnesium sulfate sub-type brine.Finally,the sedimentary evolution law of deep brine potassium resources is analyzed from the topographic,tectonic and climatic conditions in order to provide basic information for the deep evaluation,development and utilization of deep brine resources in Qaidam Basin.