鄂尔多斯盆地东部石千峰组浅层气藏成藏机理探讨

指出鄂尔多斯盆地东部石千峰组浅层气埋藏浅、勘探成本低,是鄂尔多斯盆地天然气勘探的新领域;石千峰组浅层气藏具有轻组分含量高、压力与压力系数低的特点,主要受砂岩岩性控制。又指出燕山运动使盆地东部地层抬升和剥蚀并导致下部石盒子组等超压地层超压释放;超压释放过程使石盒子组上部厚层泥岩产生了大量微裂隙,天然气主要通过微裂隙向上运移至上部石千峰组千5砂岩储层中并聚集成藏。据此认为,石千峰组浅层气藏是下部超压地层超压释放使作为下部盒8、山2等气藏的区域性盖层内产生一系列的泻压通道而形成的次生气藏。

DISCUSSION ON FORMING MECHANISM OF THE SHIQIANFENG FORMATION FLOWER GAS POOL IN EASTERN ORDORS BASIN

The flower gas pool of the Shiqianfeng formation has become the new exploration area because of it's the less exploration cost.The charactics of the flower gas pool is the highter scaling factor of the lighter sergment,the lower puress of the pool and the coefficient of the pool pressure.At the same time,the flower gas pool was controlled by sandstone reservoir.the flower gas pool of Shiqianfeng formation is the Secondary gas pool.During the Yanshan movement,the formation in eastern Ordos basin was been lifted and eroded,the surpressure lay out the down formation such as the Shihezi formation and Shanxi formation was been released.when the surpressure being released,aboundance of microfissure was been made in the mud which was made the well regional cover,and became the mainly pathway of the gas from source rock to the Shiqianfeng sandstone reservoirs.