A seismic array of twenty four seismometers (Qiaojia array) operated by the Institute ofGeophysics , China Earthquake Administration was situated along the Zemuhe fault and the north end of Xiaojiang fault, which is a part of the east boundary of the Chuan-Dian (Sichuan-Yunnan) rhombus crustal mass. The Qiaojia array started operation at the endof February , 2012. Since then the April 20, 2013 Lushan MS7. 0 earthquake and the August 3, 2014 Ludian MS6. 5 earthquake have occurred in the vicinity of the Qiaojia array. The earthquake catalogue recorded by the Qiaojia array since March, 2012 is usedin this study. The temporal variation of the earthquake count before the Lushan event and the Ludian event is analyzed. The results are as follows: ① A very clear graduallyincreasing variation of the count of M≥2. 0 earthquakes within the region, where all earthquakes recorded by the Qiaojia array coverage can be found before the Lushan event and the Ludian event, and the increasing range and duration of the count before theLudian event are both larger than those before the Lushan event. ② In the region covered by the Qiaojia array, for earthquakes with depth h≤10km a rising process of the countwas manifested before both events , along with a nearly same duration of about five and a half months, and for earthquakes with depths h > 10km a rising-dropping process of thecount was manifest before the Lushan event , before which the rising-dropping process appeared again. The variation of the count for earthquakes with depth h≤10km is thereverse of that for earthquakes with depth h > 10km. ③ Within and near the region covered by the Qiaojia array, the variation of the count manifests a rising process forearthquakes with depth h≤10km or h > 10km before the Lushan event and only for earthquakes with depth h ≤10km before the Ludian event. The variation of the countmanifests a weakening process for earthquakes with depth h > 10km before the Lushan event. It is shown from the above results that the seismicity within and near the region covered by the Qiaojia array showed a steeply rising change before both the Lushan event and the Ludian event. This phenomenon could be revelatory to understanding the process of seismicity development.
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