微生物岩储层特征及主控因素——以塔里木盆地下寒武统肖尔布拉克组为例

Reservoir characteristics and main controlling factors of microbialite: a case study of the Lower Cambrian Xiaoerbulake Formation, Tarim Basin

高洁,魏丹,张昆

GAO Jie, WEI Dan, ZHANG Kun

中国石化西北油田分公司勘探开发研究院，新疆 乌鲁木齐 830000

Exploration and Development Research Institute, Northwest Oilfield Company, SINOPEC, Urumqi 830000, China

塔里木盆地下寒武统肖尔布拉克组广泛发育微生物岩，具有良好的油气勘探前景。文中对柯坪地区肖尔布拉克组微生物岩储层类型和特征、储集空间类型、物性特征，以及储层主控因素进行了研究。结果表明：肖尔布拉克组微生物岩主要包括凝块石白云岩、泡沫绵层石白云岩、叠层石白云岩和层纹石白云岩；储集空间包括晶间（溶）孔、溶蚀孔洞、窗格孔和微生物格架孔；不同微生物岩岩石类型的储集空间类型和物性不同，凝块石白云岩、泡沫绵层石白云岩物性最好，叠层石白云岩、层纹石白云岩次之；微生物岩的岩石类型和物性特征主要受沉积和成岩共同作用，沉积相带控制了微生物岩的分布，微生物结构决定了初始孔隙特征，大气淡水淋滤和埋藏溶蚀作用对储层进行了有效改造。

There are extensive microbialites in the Lower Cambrian Xiaoerbulake Formation in Tarim Basin, which has a good exploration prospect. Based on field outcrop, thin section observation and physical property analysis, the reservoir types and characteristics, reservoir space types, physical property characteristics and main controlling factors of microbialite in Xiaolbulake Formation in Keping area have been studied. The result shows microbialites of the Xiaoerbulake Formation are composed of thrombolite, spongiostromata, stromatolite and laminated dolomite. The reservoir space mainly consists of intercrystalline(dissolution) pores, dissolution pores, fenestrule pores and framework pores of microorganism. Different type of microbialites have different reservoir space types and physical properties, among which the physical properties of thrombolite and spongiostromata dolomite are the best, followed by stromatolite and laminated dolomite. The rock types and physical properties of the microbialites are mainly influenced by the combined action of sedimentary and diagenesis. Sedimentary facies control the distribution of microbialites, microbial structure determine the initial pore characteristics, and the meteoric water leaching and burial dissolution effectively improve the reservoirs.

10.6056/dkyqt202201009