应用2011年1月-2015年4月柯坪块体及周边数字地震台站（38°-42.5°N，75°-80.5°E）记录的3.0 ≤ M ≤ 5.0地震事件，结合柯坪块体介质品质因子和各台站场地响应，计算各地震应力降、地震矩、震源破裂半径、拐角频率等新震源参数，并研究各背景值变化特征及彼此间对应关系。结果表明：柯坪块体地区地震震级与地震矩、矩震级、震源尺度之间表现为较好的正相关性，与地震拐角频率之间呈负相关。地震矩与震源破裂尺度整体呈正相关，但当震源破裂尺度较小时，地震矩变化不大，当震源破裂尺度大于250 m时，地震矩随震源破裂尺度的增大变化较快。由柯坪块体应力降时间分布特征分析可知，研究区具有地震前应力降呈现高值异常、震后缓慢恢复低值的演化过程。
Applying the data of 3 < MS < 5 small seismic event data recorded by the digital seismic stations in in Keping and its surrounding area (38°-42.5°N, 75°-80.5°E) form January, 2011 to April, 2015, combined with the Keping block medium quality factor and the site response of each station, the seismic stress drop and seismic moment, source radius, corner frequency and source parameters are calculated, the background value and the relationship between each other are also studied. The results showed that seismic moment magnitude, moment magnitude, focal size of small earthquakes in Keping block region showed a good positive correlation, and negatively correlated with corner frequency of earthquakes. The seismic moment and the rupture scale on the whole are positively correlated, but when rupture scale is small, the seismic moment changes little when the rupture scale is larger than 250m. The seismic moment scale increases rapidly with focal rupture. The time distribution analysis of stress drop in Keping block shows an evolutional process of rapid dropping before earthquake and slow recovery after earthquake.
2018,39(6): 7-15 收稿日期：2018-05-29
DOI：10.3969/j.issn.1003-3246.2018.06.002
基金项目：新疆科学基金课题（项目编号：2015205）
作者简介：南芳芳(1990-),女,助理工程师,主要从事地震监测工作。E-mail:1429673874@qq.com
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