Active Normal Faulting along the Langshan Piedmont Fault, North China: Implications for Slip Partitioning in the Western Hetao Graben

AbstractThe northwestern margin of the Hetao Graben, North China, is bounded by a pronounced 160-km-long Langshan Piedmont fault (LPF). The kinematics and recent tectonic activity of this rift-border fault and its accommodated extensional strain can help us better assess the seismic potentials. In this study, on the basis of high-resolution satellite images, digital elevation models acquired by small unmanned aerial vehicles using structure-for-motion techniques, field observations, and radiocarbon (14C) age dating, we demonstrate that (1) the LPF is a Holocene active normal fault with an average dip of ∼60°; the extension rate is estimated to be ∼0.4–0.7 mm/y, lower than geodetic strain rate; (2) the ongoing tectonic activity along this fault has played a significant role in controlling the present topography of the Langshan Mountains and neighboring areas; (3) slip partitioning probably occurred in the western Hetao Graben; namely, normal slip dominated the basin-bounding faults, and right-lateral slip ...