塔里木盆地和田河气田及其周缘地区奥陶系碳酸盐岩储集层特征探讨

奥陶系碳酸盐岩储层是塔里木盆地和田河气田及其周缘地区一套重要的勘探目的层,从中已发现了天然气.和田河气田及其周缘地区奥陶系碳酸盐岩主要在岩溶、裂缝、沉积环境等因素控制下,形成了复杂的储层空间,其中以溶蚀孔洞和裂缝最为重要;而且各个地层单元的物性也表现出较大的差异性,以蓬莱坝组潜山型白云岩储层的物性最好,鹰山组次之,良里塔格组的灰岩物性最差.和田河气田及其周缘地区发育3期古风化壳岩溶,5期构造裂缝,而多期构造缝（尤其是喜马拉雅期构造缝）与构造期后岩溶、古风化壳岩溶作用相互叠加,再加上沉积环境的共同影响,形成了复杂的岩溶体系，有效地改造了奥陶系碳酸盐岩的储集孔隙空间。

Characteristics of Ordovician Carbonate Reservoirs in Hetian River Gasfield and Its Adjacent Areas

Ordovician carbonate is an important exploration target in the Hetian River Gasfield and its adjacent areas. Natural gas has been found in the region. Controlled by karst, cracks and sedimentary environments, the reservoir pore structure in Ordovician carbonate is very complex, and dissolution caves and cracks are the most important accommodation spaces. The petrophysical properties of various Ordovician stratigraphic units are different. The dolomite in the buried hill of Penglaiba Formation is the best reservoir, and the limestone of Lianglitage Formation is the worst reservoir, and Yingshan Formation is in the between. Three stages of weathering crust karst and five stages of structural fractures developed in the Hetian River Gasfield. Multiple stages of structural fractures (especially the structural fractures developed during the Himalayan movement), posttectonic karst and paleo-weathering crust karst have influenced and spliced each other. These factors and the sedimentary environment controlled the complicated karst system of the Hetian River Gasfield, and they effectively improved reservoir pore space of Ordovician carbonate together.