The West Qinling Fault in the Tibetan plateau, an active left–lateral strike-slip fault, was proposed as the source of the earthquake, although there is no seismological evidence to prove this. In the centuries since the event, the fault has not produced any major earthquakes.[4] Another proposed source is the adjacent Tongwei thrust fault, although little is known about its associated seismic activity. No surface ruptures from the earthquake has been documented, suggesting it may be a buried rupture earthquake.[5]
The earthquake gained notable scientific attention due to the triggering of over 300 large landslides. Many of these slides consisted of several meters of loess and mudstone deposits along steep mountainsides near the Wei River. Three of the largest landslides in Pan'an, Tianshui, Gangu County, had a combined volume of 6.06 × 108m3.[6] Locating the distribution of landslides using Google Earth found a dense concentration of occurrence along the Tongwei Fault.[5]
All structures including government offices, schools, temples, and homes in Nanxiang were destroyed. It was reported that the only surviving structure was a portion of the brick city wall at the northeast corner of the city. Over 40,000 people were killed in the city. Another 30,000 people died in Yongning when massive landslides buried many homes in the area. Ground effects were severe; large fissures appeared and the landscape was deformed.[2] A large landslide completely buried Yongning Ancient Town during the quake.
InTianshui, the earthquake collapsed Confucian Temples and homes. Ground fissures and landslides killed some residents. Smaller fatality figures were reported in other parts of Gansu Province. The earthquake also affected Shaanxi and Henan provinces.[2]
^ abYueren Xu; Du Peng; Li Wenqiao; Tian Qinjian; Chen Lize (2020). "Relationship between the landslides triggered by the Tongwei M 71/2 Earthquake in 1718 AD and the disappearance of Yongning ancient town". Earthquake Research in China. 34 (4): 546–559. doi:10.19743/j.cnki.0891-4176.202004005.
^Ping Sun; Rongjian Li; Hao Jiang; Ogbonnaya Igwe; Jusong Shi (2017). "Earthquake-triggered landslides by the 1718 Tongwei earthquake in Gansu Province, northwest China". Bulletin of Engineering Geology and the Environment. 76 (4): 1281–1295. Bibcode:2017BuEGE..76.1281S. doi:10.1007/s10064-016-0949-4. S2CID132033294.