Division of the tectonically reworked areas and delineation of the favourable areas for hydrocarbon accumulation in the Qiangtang Basin

The Qiangtang Basin in the hinterland of the Qinghai-Xizang Plateau is interpreted as a reworked basin which has undergone multiple phases of tectonic reworking.The integration of outcrops,metamorphism,volcanism and magmatism,and structural deformation of the strata in the basin permits the division of the basin into three provinces: slightly reworked area;moderately reworked area and highly reworked area.In addition,the combination of source rocks,reservoir rocks,cap rocks,preservation,structural conditions and oil and gas shows in intergration with multiple information results in the delineation of the basin as the favourable area,raletively favourable area,poor area and unfavourable area for hydrocarbon accumulation.The Tupoco-Quedanco-Bandaohu,Baitanhu-Botaohu,East Biluoco-Tumain and Changliangshan-Heijianshan zones are considered as favourable areas for hydrocarbon accumulation in the Qiangtang Basin.