Abstract:

Earthquakeinduced deformational structures mainly include the smallgrade tensional or compressional fault, the inconsistent fold of soft sediment, which are marked by shock deformation; thus, these structures become the main discerning marks for seismites. Many typical earthquakeinduced deformational structures developed in the third member of Mesoproterozoic Gaoyuzhuang Formation in Xuanhua County of Hebei Province, and these structures include the obvious intrastratal fault, the intrastratal fold and the cataclastic breccia and so on. The earthquakeinduced structure in the third member of Mesoproterozoic Gaoyuzhuang Formation provides an important example for both the study on not only the reconstruction and the destruction of depositional rock beds generated by earthquake but also the distinguishability from other event deposits such as the storm and the tsunami deposits, and also provides an important information for the formation setting of the third member of Gaoyuzhuang Formation that is marked by a nonstromatolitic succession of the Precambrian.

Key words: earthquakeinduced deformational structure, third member of Gaoyuzhuang Formation, Mesoproterozoic, Xuanhua County of Hebei Province