深埋藏条件下相对优质储层形成因素分析——以鄂尔多斯盆地高桥地区盒8、山2砂岩储层为例

Analysis on the forming factors of relatively high quality deep buried reservoir——taking Ordos Basin Gaoqiao area He 8 and Shan 2 sandstone reservoir as an example

一般认为,砂岩储层的孔隙度与渗透率将随着深度的增加而降低。然而,随着鄂尔多斯盆地勘探开发的逐步加深,在深埋藏(>3500m)的砂岩储层中也发育较好的储层,尤其在鄂尔多斯盆地高桥地区的盒8和山2段局部就形成了,粒间孔大量残余为主要储集空间的储集体,形成了深埋藏低渗透背景下的相对优质储层。本文通过偏光显微镜、包裹体测温、恒速压汞、成像测井等技术方法,对沉积、成藏、成岩等方面进行讨论,认为岩石成分高成熟度、早期的烃类充注、早期胶结作用、晚期溶蚀作用及高角度构造缝的发育,是形成高桥地区盒8、山2段砂岩深埋藏条件下相对优质储层的主要因素。

Generally, porosity and permeability of sandstone reservoir will decreased with in- creasing depth. However, with the exploration and exploitation of Ordos basin, deep burial （ 〉 3 500 m ） sandstone reservoir is developed. Especially in Ordos Basin Gaoqiao area he8 and Shah2 formation, large amounts of residual intergranular pore is the main reservoir space of the reservoir, which leads to deep buried relatively high-quality reservoir of low perme- ability background. In this paper, combining with polarizing microscope, inclusion thermome- try, rate-controlled mercury, imaging logging, deposition, diagenesis, the conclusion that such factors as rock composition of high maturity, early hydrocarbon filling, early cementa- tion, advanced corrosion and structural fracture form high-quality reservoir in Gaoqiao area He 8, Shan2 sandstone.