The Lixian-Luojiapu Fault Zone located at the triple junction between the
normal sense of slip, and strikes in an east northeast direction. It formed in the late Quaternary as a system of three fault strands with a length of 150 km. The fault has an average horizontal and vertical displacement rate of 0.95 mm/yr and 0.35 mm/yr respectively. Surface ruptures on two segments of the fault zone; the Tanchang-Lixian and the eastern Lixian-Luojiapu subsegments, were positively identified and corresponded to the event. The earthquake rupture also involved one on the West Qinling Fault, located north of the Lixian-Luojiapu Fault Zone. The West Qinling Fault is another major left-lateral fault that strikes west northwest and runs for a much longer length.[4]
The rupture on the Lixian-Luojiapu Fault Zone is also consistent with the reported isoseismal intensities obtained from the historical records. It is estimated that the total rupture length on the structure was 106 km. Paleoseismology studies on the West Qinling Fault found surface ruptures which were dated and corresponded to the event.[4] A recent (2022) study of earthquakes in the region reevaluated the magnitude to 7.0 Mw , a revision from older studies that estimates it to be 8.0 Mw .[1]
Impact
There were 30,000 fatalities, many injured and missing.
ground fissures. At Wushan, many villages and fortifications were destroyed.[6] In nearby Fufeng County, Shaanxi, residents and animals died in the collapse of walls, temples and the Jinfu Palace. Damage to city walls were reported in Hanzhong.[6]
