济阳坳陷早第三纪震积岩的发现及其意义

济阳坳陷下第三系沙河街组三段及四段地层中发现了大量与地震活动有关的变形构造,如微断层、层内小褶皱、液化砂岩脉、振动液化卷曲变形和火焰构造等。通过牛110、利 981、车古 201和义 377等井的系统观察,发现震积岩的垂向序列自下而上依次为震裂岩和震塌岩层段、阶梯状正断层层段、振动卷曲变形层段、液化砂岩脉层段、碎块层段和均一层段,分别对应于强震期、地震衰减期和余震期。震积岩的发现不但有助于分析判断控盆边界断裂的强烈活动时期,震积岩自身也可能是一种潜在的油气储集体,因而地震事件沉积具有重要的研究意义。

DISCOVERY AND SIGNIFICANCE OF EARTHQUAKE EVENT DEPOSITS OF EARLY TERTIARY IN THE JIYANG DEPRESSION

Seismic activity is a familiar catastrophic geologic event. Many earthquake related deformation structures were discovered in the Shahejie Formation of Lower Tertiary in the Jiyang Depression, such as micro faults, pleated within layers, liquefaction sandstone veins, vibrational liquefaction deformation structure and flame structure. According to the systematic study of the Wells of Niu 110, Li 981, Chegu 201 and Yi3 7 7, the vertical succession of seismites, in ascending order, was shattered rock bed, ladder shaped faulted bed, vibrational liquefaction deformation structure bed, liquefied sandstone vein bed, rubble bed and homogenized bed, which were corresponding to strong shock period, attenuation period and aftershock period of earthquake respectively. It had important significance to study earthquake event deposits. The discovery of seismites could be used to analyse the intensively active period of basin controlling boundary fault, and the seismites themselves were a kind of potential reservoir.