Abstract：In this paper, the anomalies of fault deformation before the Aug. 8th, 2017 Jiuzhaigou MS7.0 earthquake, and their variations after the quake, are analyzed. We use the data of across-fault short-leveling at the northeastern margin of Qinghai-Xizang block, together with added data observed in August and September after the quake, with the aid of observational curves and time-space evolution of the anomalies, as well as the index of feature intensity. The results show that: Over one year before the earthquake, the anomalies are relatively concentrated at the area from western Qinling to Liupanshan tectonic region; 1-3 months before the earthquake, short-term anomalies at the western Qinling tectonic region and nearby display an increasing trend within the distance of 300 km of the epicenter; this mainly reveals abrupt thrust change characteristics, which have medium-short-term and short-term precursory features; one month after this earthquake, most anomalies had adjusted and recovered.
ZHANG Xi,JIA Peng,LI Ruisha et al. Precursory Anomalies of Across-Fault Leveling before the Jiuzhaigou MS7.0 Earthquake and Variation after the Quake[J]. jgg, 2018, 38(11): 1101-1106.
