柴北缘石泉滩和冷湖三号储层特征对比研究

Contrast Research on Reservoir Characteristics Between Shiquantan and Lenghu 3 in Northern Margin of Qaidam Basin

为了查明柴达木盆地北缘石泉滩与冷湖三号地区位置毗邻,储层产油性却相差甚远的原因.运用沉积岩石学和储层研究的原理和方法,对石泉滩和冷湖三号地区下侏罗统小煤沟组储层,分别从沉积相、岩矿组成、岩石结构、孔隙结构、成岩作用和物性特征等方面进行对比研究.结果表明,石泉滩地区储层砂体为扇三角洲平原沉积,岩石刚性碎屑含量高、属孔隙式胶结、具较好的孔隙结构特征、曾受强压实和溶蚀作用、主要类属于中高孔—低渗储层.总的来说,含油性能要优于冷湖三号地区,但由于砂体厚度、构造活动和地层接触关系等诸多因素的影响,在产油方面却不及冷湖三号地区.

In order to identify the reason that Shiquantan, being contiguous to Lenghu 3, has much less production of oil and gas than Lenghu 3. With the theory and means of sedimentary petrography and reservoir study, the sedimentary facies, rock-mineral composition, rock texture, pore structure, diagenesis and physical property of the reservoir of low Jurassic Xiaomeigou formation between the areas of Shiquantan and Lenghu 3 in northern margin of Qaidam basin have been contrasted and studied. The results show that the reservoir sandstone of Shiquantan was formed in an environment of fan delta plain, which belongs to medium-high porosity-low permeability with high content of rigid detritus, pore cementation, good pore structure characteristics and strong consolidation and corrosion, and exhibits higher oil-bearing property than that of Lenghu 3. As the effects of thickness of sand bodies, tectonic movements and stratigraphic contact relationships, the oil and gas production is less than that in the area of Lenghu 3.