酒西盆地青西油田白垩系泥云岩裂缝油藏特征和裂缝形成的控制因素

CHARACTERS OF A SPECIAL ROCK-FRACTURED RESERVOIR AND FACTORS OF CONTROLLING FRACTURED DEVELOPMENT AT QINGXI OIL FIELD IN JIUXI BASIN

酒西盆地青西油田深层泥云岩裂缝性油藏是一种罕见的油气藏类型。在该油藏特低孔、特低渗泥云岩储层中发育的裂缝是油、气等流体的渗流通道和主要储集空间并形成了"自生自储"的富油成藏组合,具有井间产能相差悬殊、初产递减快和弹性产率变化大、酸化改造效果不一等特点。控制裂缝形成的地质因素复杂,主要有构造、岩性和成岩作用等,岩性特征是控制裂缝发育的基础,构造作用是控制裂缝发育的关键因素,成岩作用是影响裂缝发育的重要条件。

Rare is a special deep rock (muddy dolomite, dolomite mudstone, dolomite)-fractured oil reservoir at Qingxi Oil Field in Jiuxi Basin. In this reservoir which has lower porosity and permeability, fracture becomes major storable-permeable spaces and forms a good 'autochthonous source and autochthonous reservoir' source-reservoir-seal assemblage. Furthermore, there is a great difference in wells production, acidization effect, etc. And the fractured formation factors which include structures, lithological characters, diageneses are studied. This study have certain theoretical meanings and practical values.