与断层相关的假玄武玻璃是地震作用的产物,是古地震的可靠记录.登封大断层是嵩山地区的主要断层之一,在登封大断层的分支断层及断层破碎带内首次发现了假玄武玻璃.假玄武玻璃呈黑色,以脉状、网脉状和树枝状贯穿石秤钾长花岗岩体.断层带内还发育有未固结的红色断层泥.显微镜下研究表明,假玄武玻璃中的碎屑颗粒以碎裂成因的钾长花岗岩为主,还有部分碎屑颗粒呈港湾状的熔蚀结构.这表明假玄武玻璃的成因以同震断层的碎裂作用为主,伴随有少量的高温熔融过程.古文献记录表明,夏代末年偃师一登封地区有大地震活动,结合未固结的断层泥特征,该地区的地震活动可能与登封大断层的活动有关.
Pseudotachylytes related with faults are formed by coseismic friction and they are fossils of earth- quakes. The Dengfeng Fault is one of the biggest faults in Songshan Region, and this paper reports the first finding of pseudotachylytes in the Dengfeng Fault and its secondary fracture zone. Pseudotachylytes are dark in color and hosted in Shieheng kaligranite in dykes, viens and branch-likes forms. Besides pseudotaehylytes, fault gouge are fomed in the fracture zone too. The gouge are red in color and unconsolidated yet. The frag- ments in pseudotachylyte veins are mainly consisted of cataclastic kaligranite rocks, while some fragments are embayed quartz, indicating partial melting under high temperature. Ancient documents mentioned that a big earthquake occurred at Yanshi-Dengfeng region on late Xia dynasty. Combined with the unconsolidated gouge, the big earthquake may be related with the Dengfeng Fault.