The seismic reflection data collected across central southwestern Guizhou clearly revealed the coal measures of upper Permian Longtan Formation and Dongwu and Guangxi unconformities in Carlin-type gold deposit.Most Carlin-type gold deposits are controlled by thrust-fold in this area.Based on seismic profile,the gold deposits could be divided into two types,i.e.,thrust-controlled and thrust-accompanied deposit according to the position of deposit in the thrust-fold belt.In thrust-controlled deposits,the thrust with steep dip in superficial part and shallow dip in deep level was detached from coal measures,tuffs and Dongwu unconformable contact;fault-related fold always occurred on the hanging wall block;gold ore bodies occurred in thrust with vein shape in shallow level and low angle strata-dissecting shape in deep level.The thrust-accompanied gold ores occurred in interlayer-gliding structures caused by high-angle faults with stratiform-like ore bodies.Northwestern and northeastern trending thrust-fold zone were generated by successional closure of Paleo-Tethys Ocean in South China during the late Indosinian epoch.The seismic data also show that there are some thrust-folds similar to the structure of the structure zones where Carlin-type gold deposits were discovered,suggesting an ore prospective area.%地震勘探资料对黔西南中部卡林型金矿赋存层位上二叠统龙潭组煤系地层、东吴不整合面和广西不整合面显示良好。该地区卡林型金矿主要受冲断-褶皱构造的控制。在地震剖面上,根据卡林型金矿在冲断-褶皱构造中的位置,可以将其划分为两类,即断层控制型金矿和断层伴生型金矿。在断层控制型金矿床中,断层＂上陡下缓＂,为低角度逆冲断层,断层上盘常发育不对称背斜构造,断层向下在上二叠统龙潭组煤系地层、＂大厂层＂凝灰岩和东吴运动形成的不整合面间滑脱,金矿体产于低角度逆冲断层中,在浅部为脉状矿体,在深部渐变为缓斜穿层矿体。断层伴生型金矿床发育于由高角度断层引起的层间滑动带,呈似层状。印支晚期华南古特提斯洋的相继闭合是形成北西向和北东向两组主要冲断-褶皱构造的主控因素。地震勘探资料揭示,黔西南中部还存在与已经发现卡林型金矿的冲断-褶皱构造带类似的构造,找矿前景较好。
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