罗布泊罗北西3号断陷带固体钾盐矿地质特征及成因分析

经遥感解译及地表调查,在罗布泊新庆台地罗北西3号断陷带内存在固体钾盐矿化带。为初步查明该断陷带钾盐矿化带的矿体赋存特征、矿物组分、矿石类型及矿体规模,开展了系统的坑探揭露、刻槽取样、盐矿鉴定、X射线衍射及化学分析测试等工作。经勘查,钾盐矿层赋存于洼地内第四系全新统化学沉积层中,呈似层状分布。面积约30 km²,矿层厚0.30～2.73 m,平均1.02 m。经X射线衍射及盐矿鉴定,矿石中含钾矿物以杂卤石为主,钾盐镁矾次之,局部见含光卤石,矿石中KCl含量在2.07%～8.44%,平均含量在3.55%。通过本次研究,确认该区存在一低品位固体钾盐矿床,初步查明了矿床地质特征,其成因为台地内的局部洼地汇水经蒸发作用沉积形成,为进一步的勘查及开发提供了地质依据。

Geological Characteristics and Genesis of the Solid Potash Salt Deposit in the No.3 Fault Depression Zone in Northwest Lop Nur

Through remote sensing interpretation and surface investigation,there is solid potassium salt mineralization in luobeixi No.3 fault depression zone of Xinqing platform in Lop Nur.In order to preliminarily find out the occurrence characteristics,mineral composition,ore type and ore body scale of the potassium salt mineralization zone in the fault depression zone,systematic pit exploration and exposure,slot sampling,salt ore identification,X-ray diffraction and chemical analysis and testing have been carried out.According to the exploration,the potassium salt mineralized layer occurs in the middle and upper part of the Quaternary Holocene chemical sedimentary layer in the depression.It is distributed like a layer,with an area of about 30km²,an ore thickness of 0.30~2.73m,with an average of 1.02m.The potassium containing minerals are mainly polyhalite,followed by potassium salt magnesite,and carnallite is seen locally.The KCl content in the ore is 2.07%~8.44%,with an average content of 3.55%.Through this research work,it is confirmed that there is a low-grade solid potassium salt deposit in this area,and the geological characteristics of the deposit are preliminarily found out.It is caused by the evaporation and deposition of local depression catchment in the platform,which provides a geological basis for further exploration and development.