Gravity variations before the Menyuan Ms6.4 earthquake

In order to study the relationship between gravity variation and Menyuan Ms6.4 earthquake, gravity variation characteristics in mid-eastern of Qilian Mountain were analyzed based on the 2012–2015 relative gravity datasets. The results indicated that the gravity changes in mid-eastern of Qilian Mountain increased gradually, while gravity changes around Menyuan remarkably. Besides, great positive-negative gravity changing gradients appeared along the Lenglongling Fault which was located at the north of Menyuan, and the 2016 Menyuan Ms6.4 earthquake occurred near the junction of positive and negative gravity changes.