四川西南部周公山及邻区“峨眉山玄武岩”特征及储集性能研究

The Study on Reservoir Property and Characteristics of the Emeishan Basalts of Zhougongshan and Its Neighbour Area in the Southwest Sichuan

川西南部周公山及邻区上二叠统"峨眉山玄武岩"厚40～500m,由12个旋回性玄武质火山岩构成。每一旋回底部的火山角砾岩和上部的气孔—杏仁状玄武岩常具有一定的储渗能力,储渗空间以气孔、柱状节理缝、构造裂缝为主,属于低孔、中渗或低孔、高渗型储层;其余层段如无构造作用的叠加,多构成非储集岩类。在该套储层的形成与演化过程中,岩浆的冷凝收缩、构造断裂和大气淡水、地层水溶蚀作用和有机质成熟过程都促进了储渗空间的形成,而热液蚀变作用、四期胶结作用和三期充填作用对储集空间起着明显的破坏作用。

In the southwest of Sichuan, Upper Permian Formation, the thickness of Emeishan basalts of Zhougongsban and its neighbor area is from 40m to 500m, and it is formed by 12 cyclic basaltic volcanic rock. The volcanic breccias in the bottom and the stomatal basalts in the upper have some reservoir capability in cyclicity. The reservoir spaces mainly are air voids, basahia jointing split and tectoclase. Generally, they form lower porosities, medium per- meability or lower porosities, higher permeability reservoirs. In other sections, if there are not the superposition of teetonic movement, most of them can not form reservoir rocks, during the formation and evolution of this set of reservoirs, the condensation contract fissure of magmatic melt, tectonic rupture, organic maturation and chemical erosion. All of these have promoted the forming of reservoir spaces. But hydrothermal alterations and 4 stage cementation and 3 stage packing action have obvious damage affection to reservoir spaces.