Characteristics of fault block movements of the Tangyuan fault depression in northeastern Heilongjiang, China and their controls on hydrocarbon accumulation

The characteristics of movements of the basement and various fault blocks in the Tangyuan fault depression are studied by applying the theory of tectonic movements and based on the geological, geophysical and drilling data. The study indicates that the basement of block IV in the Tangyuan fault depression has a maximum amount of extension, while the block V basement has a minimum amount of extension. Examples from 15 blocks suggest that there is appreciable difference in extent of tilting movements of fault blocks in different tectonic settings and stages. The tectonic movements of the fault blocks in the Tangyuan fault depression controlled the types of hydrocarbon reservoirs. Extensional and transpressional movements resuited in the formation of structural hydrocarbon reservoirs. The early and middle stages of the extensional movement formed lithological reservoirs in synclines and the tilting of fault blocks and uplift/denudation formed stratigraphic reservoirs.