Abstract:

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.

Key words:  thrustfold structure, Carlintype gold deposit, seismic data, central southwestern Guizhou