摘要
详细分析了鄂尔多斯盆地三叠系延长组野外砂岩墙和岩心砂岩脉的特征，初步弄清了砂岩墙（脉）的形成机制和演化过程：早期沉积的未固结细粒砂岩在后期地震诱发下液化，同时砂体内压力迅速增加，在围岩层的裂隙处闪电般贯入，形成砂岩墙（脉）。结合区域构造背蒂，认为砂岩墙具有构造指示意义，同时对油藏的形成和破坏具有一定的影响。
Characteristics of field sandstone dike and sandstone vein in cores of the Triassic Yanchang Formation of Ordos basin are analyzed in details. The formation mechanism and evolution process of the sandstone dike （vein） are clarified elementarily： Early-deposited unconsolidated fine-grained sandstone was liquified under the late earthquake inducement and the pressure inside the sand body increases rapidly. The sandstone penetrated into the cracks in wall rock like lightning, and formed sandstone dike （vein）. With the regional tectonic background, it is considered that the sandstone dyke has tectonic indication effect. Meanwhile it has some influences on the reservoir formation and destruction.
基金
国家重点基础研究发展规划“973”项目（编号2003CB4607）资助的成果.
关键词
鄂尔多斯盆地
延长组
砂岩墙(脉)
地震
Ordos basin
Yanchang Formation
Sandstone wall （veins）
Earthquake action
