Evidences of Cenozoic Strike-Slip Dislocations of the Red River Fault System in Paleozoic Carbonate Strata of Cat Ba Island (Northern Vietnam)

摘要

The structural researches of carbonate strata in the northeastern segment of the framework of the Red River Fault System (Cat Ba Island, Northern Vietnam) has been carried out. It was found that weakly deformed carbonate strata are cut by NW-trending (300-310°) strike-slip faults. Development of plicative and disjunctive dislocations occurred along predominantly sinistral strike-slip fault zones formed as a result of ENE regional compression (80°) during the Oligocene-Miocene phase of deformation. Late dislocations confined to the Pliocene-Quaternary phase of deformation (NNW regional compression 330-350°), are relatively less developed. Seismic monitoring data show that both plicative and disjunctive dislocations have continued to the present.