和田河气田奥陶系碳酸盐岩裂缝

FRACTURES OF ORDOVICIAN CARBONATE ROCKS IN HETIAN RIVER GASFIELD

杨威 王清华 赵仁德 刘效曾

Yang Wei Wang Qinghua Zhao Rende

和田河气田奥陶系碳酸盐岩中发育3类成岩缝和5期构造缝。裂缝以高角度小微缝为主,多数裂缝被方解石和泥质充填或半充填。缝合线和2,3,4,5期构造缝尚存在未被充填的空间,可作为油气的储集空间和渗流通道。裂缝是储层渗透率的主要贡献者,总渗透率的99.4%为裂缝提供。裂缝的发育程度主要受控于构造运动和岩性,而与不整合面和地层负荷关系不大。

Three sorts of diagenetic fractures and five stages of structural fractures developed in Ordovician carbonate rocks in Hetian River Gasfield.Their characters of development time,attitude,scale,packing degree and so on are different each other.The fractures are characterized by high angle and small micro fractures,most of them are filled by mud and calcite.The suture and 2～5 stage structural fractures contain spaces for hydrocarbon preservation and migration.Fractures are the principal contributors of permeability(supplying 99.4% of total permeability),and it is the main cause for carbonate rocks to be efficient reservoirs.development degree of fractures was controlled by lithology and tectonic movement.

10.11743/ogg20000314