山西沁源隐伏铝土矿综合物探调查应用效果  

THE APPLICATION OF INTEGRATED GEOPHYSICAL EXPLORATION TO CONCEALED BAUXITE DEPOSITS IN QINYUAN OF SHANXI PROVINCE

作　　者：徐新学 李世斌 袁航 曹鹏军 郑国磊 郑军 

机构地区：[1]天津市地球物理勘探中心,天津300170

出　　处：《物探与化探》2014年第1期41-45,共5页Geophysical and Geochemical Exploration

摘　　要：铝土矿床受控于奥陶系灰岩构成的古地貌,与成矿盆地内赋矿地层石炭系本溪组的厚度正相关,盆地斜坡带、洼地、凹槽及岩溶漏斗地段是铝土矿富集有利部位。奥陶系灰岩与上覆地层有较明显的密度和电性差异,铝土矿体与围岩也存在密度差。借助于可控源音频大地电磁测深法(CSAMT)及钻孔的标定,利用重力异常可以了解研究区的构造格架和奥陶系灰岩基底的起伏变化,确定局部高密度体的赋存状况及性质,并大致确定其埋深。在山西沁源成矿远景区中深部隐伏铝土矿调查中,采用1∶2.5万重力和CSAMT法直接与间接找矿相结合的方法取得了较好的应用效果,为钻孔布设提供了依据。Controlled by the ancient terrain composed of Ordovician limestone, the bauxite deposit is positively related to the thickness of Carboniferous Benxi Formation in the ore-forming basin, and the favorable positions for bauxite enrichment are slope belts, depres-sions, grooves and karst funnels. As there exist obvious differences between Ordovician limestone and overlying formations in density and electrical properties and between bauxite and surrounding rocks in density, Bouguer gravity anomaly can better reflect the tectonic framework in the study area and the rise-and-fall trend of the Ordovician interface, Bouguer gravity residual anomaly can reflect the oc-currence of partially high percentage of bauxite, and the combination of controlled source audio-frequenay magneto-telluric （ CSAMT） method and calibration of the drilling can efficiently infer the buried depth and occurrence of basement limestone. The authors have a-chieved good application result by using 1 ∶ 25 000 gravity and CSAMT method which combines direct prospecting and indirect prospec-ting, and the results provide a basis for deploying drill holes.

关 键 词：隐伏铝土矿 重力 CSAMT 山西沁源 

分 类 号：P631[天文地球—地质矿产勘探]