Guguan-Guozhen fault is one of the important faults of Longxian-Baoji fault zone, which marks the boundary of NE margin of the Tibetan Plateau and the SW margin of the Ordos block. The temporal and spatial patterns of the fault record vital information of the northeastward expansion of the plateau. The middle Guguan-Guozhen fault presents a clear linear feature on satellite and DEM images. On geomorphologic, the fault presents 80～100 m surface scarp. Multiple research methods including interpretation of satellite images, field investigation, trench excavations, and dating techniques are applied, the results show that the middle Guguan-Guozhen fault was active at the Early Quaternary and mainly conduct sinistral strike-slip faulting activity, which made use of the fault plane formed at the Early Cretaceous. After the Late Pleistocene, the fault stopped faulting activity. The cause of the transform of the fault behavior is that, the regional tectonic stress was changed because of the sub-blocks around the fault zone were adjusted for interactions after the remote effect of the Cenozoic India-Eurasia collision reached the NE margin of Tibetan Plateau, and the regional stress field of the study area turned into shearing stress since Quaternary.
Wang Shidi Shi Yaqin Dong Yunpeng. The active characteristics in the Quaternary period of the middle Guguan-Guozhen fault, northeast margin of Qinghai-Tibet Plateau[J]. Chinese Journal of Geology, 2018, 53(3): 781-798.