蒙古南贝尔凹陷白垩纪地震作用的证据

在区域构造背景研究和岩心观察的基础上，在蒙古南贝尔凹陷白垩纪地层中识别出震积岩。震积岩的主要标志是发育各种类型的软沉积变形构造，包括微同沉积断裂、卷曲变形构造、液化砂岩脉、震积枕状及伴生构造等，这是首次在蒙古南贝尔凹陷发现与地震作用有关的沉积特征。在塔21 9井中发现完整的震积岩垂向序列，序列自下而上分为下伏未震层、砂岩脉（砂火山）、震动卷曲变形层、内碎屑角砾岩层、阶梯状微断层和震裂缝层、震浊积岩层和上覆未震层。如此完整地震序列在同一口井岩芯中同时出现实属罕见，为进一步深入研究古地震作用提供了良好的物质组合。

The Evidence for Seismism in Cretaceous of South Beir Sag, Mongolia

Based on studies of regional tectonic background and the observation of drilling cores, the seismite is recognized which mainly occurred in Cretaceous in South Beir sag, Mongolia. Many kinds of soft sedimentary deformation structures have been found in seismite, such as step micro-faults, pleated within layers, liquefaction sandstone veins, vibrational liquefaction deformation structure and seismic breccias. It is the first time that seismite has been found in South Beir sag, Mongolia. The complete vertical sequence of seismite developed in Well Ta21-9, which include bottom unshaken layer, liquefied sandstone vein bed, vibration liquefaction deformation structure bed, intraclastic parabreccia bed, ladder-shaped faulted and vibration split bed, seismic turbidite bed and top unshaken layer. It is rare among the reported examples about such complete sequence of seismite in one Well's core, so it is a good example and offers power evidences to study seismism.