塔中I号断裂带中上奥陶统灰岩裂缝类型划分

中上奥陶统(O2+3)灰岩是塔中油气区主要的储集层,由于基质的孔隙度和渗透率极低,裂缝在储层中既是油气聚集的空间,也是油气运移的主要通道。不同类型裂缝的成因、产状、规模、以及对油气的孔、渗能力都各不相同,对它的研究有助于寻找油气的聚集与富集规律。依据对塔中I号断裂带裂缝调查的结果,按照裂缝的成因,充填物的类型、特征,以及不同充填物充填的裂缝之间的切割关系,将O2+3灰岩储层中的裂缝分为不同的大类;然后根据裂缝的产状、性质等,再将裂缝细分为不同的亚类型。结果表明:该地区裂缝类型复杂,发育有2类成岩缝和5类(期)构造裂缝,每期构造缝都发育了不同产状和性质的裂缝。

CLASSIFICATION OF FRACTURES IN O2+3CARBONATE RESERVOIRS IN TAZHONG I#FAULTED ZONE

O2+3carbonate rock is the major reservoir rock in the cen-tral Tarim basin. As the matrix porosity and permeability of the strata is very low, fractures play an important role in gathering and transporting oil and gas. Since the different types of frac-tures differ in genesis, occurrence, scale and capability in stor-age and transport of oil and gas, a detailed classification scheme is needed to probe the regularity of occurrence and enrichment of oil and gas in the reservoirs. On the basis of detailed investi-gation, the fractures are firstly divided into different types ac-cording to the genesis, type and chacteristics of the fracture-fill-ing material, and the cross-cutting relationship of fractures.Then, sub-types are determined according to the occurrence and nature of the fractures. The result shows that fractures in the area under study are complax, with 2 types of diagentic and 5 types (or periods) of structural origen, and the structural frac-tures of each period display different occurrence and characteris-tics.