老挝万象凹陷钾盐矿床变形改造富集模式  

Potash Deformation and Enrichment Modes in Vientiane Sag,Laos

作　　者：梁光河[1,2,3] 徐兴旺 Liang Guanghe;Xu Xingwang(Key Laboratory of Mineral Resources,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China;Innovation Academy for Earth Science,Chinese Academy of Sciences,Beijing 100029,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院地质与地球物理研究所,中国科学院矿产资源研究重点实验室,北京100029 [2]中国科学院地球科学研究院,北京100029 [3]中国科学院大学,北京100049

出　　处：《地球科学》2022年第1期136-148,共13页Earth Science

基　　金：第二次青藏高原综合科学考察研究(No.2019QZKK0806)。

摘　　要：呵叻盆地是特提斯成矿带重要的钾盐成矿盆地,但是其变形构造与钾盐分布规律不清而严重制约了该区域钾盐矿床的勘探与开发.在宏观区域大地构造演化分析基础上,以老挝万象凹陷中一个区块为例,实施了三维地震勘探,在高精度地震资料和钻井自然伽马测井严格约束下,得到了地下准确的构造变化和钾盐矿分布资料.结合盐构造变形特征和地震勘探剖面进行了地质解译,结果显示印支地块的挤压走滑旋转对呵叻盆地内的钾盐矿进行了强烈改造,由此总结出三种钾盐矿改造模式,分别为蒸发岩侏罗山式褶皱变形模式、应力作用下的差异载荷富集模式和围绕硬质盐丘旋转的富集模式.The Khorat Basin is an important potash basin in the Tethys metallogenic belt,but the exploration and development of potash deposits in this area are severely restricted due to the unclear deformation structure and the distribution rules of potash salts.Based on the analysis of macro-regional tectonic evolution,taking a small region in the Vientiane Sag as an example,under the strict constraints of high-precision 3 D seismic exploration and drilling natural gamma logging,the underground accurate structural changes and potash ore distribution data were obtained.Combined with the deformation characteristics of salt structure and seismic exploration profile,the geological interpretation was carried out.The results indicate that the squeeze,slip,and rotation of the Indosinian block have strongly transformed the potash deposits in the Khorat Basin.Three types of potash deposit transformation models are summarized,including evaporite Jura type fold deformation model,differential load enrichment modes under stress,enrichment mode rotating around hard salt mound.

关 键 词：老挝 万象凹陷 钾盐矿 构造运动 变形模式 矿床学 

分 类 号：P619.211[天文地球—矿床学]