Physical modeling of Xu-Huai thrust-fold belt on the southeastern margin of North China Block

Xu-Huai area has developed a series of thrust-fold belts. The regional section is divided into eastern and western tectonic zones with obvious structural differences:the eastern tectonic belt mainly shows the characteristics of inclined fold, and the western tectonic belt mainly shows the characteristics of a series of thrusts in style. In this paper, the authors studied Xu-Huai thrust-fold belt with the physical modeling method, selected silica gel and micro glass beads to simulate different decollement properties, selected quartz sand to simulate sedimentary brittle cover layer, and changed basal control factors such as friction and decollement depth. The modeling results show that the properties of decollement along the section and the depth change control the regional structural defor-mation. To the east of Huang-Cang valley anticline, main decollement is Upper Proterozoic marl of deep burial depth, and the main tectonic style is characterized by inclined fold; to the west of Huang-Cangvalley anticline, Cambrian shale serves as the decollement, and the decollement is of small depth, with the tectonic style characterized by a series of thrusts.