综合物探在吐哈盆地东部矿产勘查中的应用研究

Application of comprehensive geophysical prospecting in mineral exploration in eastern Turpan Hami basin

中侏罗统西山窑组既是吐哈盆地层间氧化带型砂岩铀矿的主要找矿目标层,也是盆地的主要赋煤层位。研究西山窑组的空间展布特征对盆地铀、煤勘查工作具有指导意义。根据可控源音频大地电磁测量(CSAMT)结果,结合吐哈盆地1∶50万重力勘探资料对盆地东部基底起伏形态以及西山窑组的分布范围、顶板埋深及厚度进行了研究分析。结果表明盆地东部西山窑组主要分布于长流水洼陷、骆驼圈子洼陷、庙尔沟洼陷及梧桐窝子洼陷等次级构造单元,其顶板埋深100~450 m,厚度200~700 m,西山窑组在凸起地段不发育或已剥蚀。通过钻孔揭露情况与物探反演结果的对比分析,验证了综合物探应用于该区矿产勘查中的有效性。

Xishanyao formation of middle Jurassic is not only the main prospecting target bed of interlayer oxidation zone type sandstone uranium deposit in Turpan Hami basin,but also the main coal hosting bed in the basin.The study on the spatial distribution of Xishanyao formation is of great significance to uranium and coal exploration in the basin.According to CSAMT survey results and 1∶500,000 gravity exploration data in the study area,the basement undulation shape,distribution range,roof buried depth and thickness of Xishanyao formation in the east of the basin are studied and analyzed.The results show that the Xishan formation in the eastern part of the basin is mainly distributed in the Changliushui sub-sag,Luotuoquanzi sub-sag,Miaoergou sub-sag and Wutongwouzi sub-sag,etc.Xishanyao formation is undeveloped or denuded in the high of the basin.The depth of the roof of Xishanyao formation is 100~450 m,and the thickness is 200~700 m.The effectiveness of comprehensive geophysical prospecting in mineral exploration in this area is verified by comparing the drilling exposure and geophysical inversion results.