中文摘要：

2014年11月22日在NW向鲜水河断裂带中南段四川康定县发生M6.3级地震,11月25日在该地震震中东南约10 km处再次发生M5.8级地震. 基于中国国家数字地震台网和四川区域数字地震台网资料,采用多阶段定位方法对本次康定M6.3级地震序列进行了重新定位; 利用gCAP（generalized Cut And Paste） 矩张量反演方法获得了M6.3和M5.8级地震的震源机制解与矩心深度,分析了本次地震序列的发震构造,并结合历史强震破裂时空分布和2001年以来小震重新定位结果,对鲜水河断裂带中段强震危险性进行了初步探讨. 获得的主要结果如下：（1） M6.3级主震震中位于101.69°E、30.27°N,震源初始破裂深度约10 km,矩心深度9 km; M5.8级地震震中位于101.73°E、30.18°N,初始破裂深度约11 km,矩心深度9 km. gCAP矩张量反演结果揭示这两次地震双力偶分量占主导,M6.3级地震的最佳双力偶解节面Ⅰ走向143°/倾角82°/滑动角-9°,节面Ⅱ走向234°/倾角81°/滑动角-172°. M5.8级地震最佳双力偶解节面Ⅰ走向151°/倾角83°/滑动角-6°,节面Ⅱ走向242°/倾角84°/滑动角-173°. 依据余震分布长轴展布与断裂走向,判定节面Ⅰ为发震断层面,M6.3和M5.8级地震均为带有微小正断分量的左旋走滑型地震. （2） 序列中重新定位的459个地震平均震源深度约9 km,地震主要集中分布在6~11 km深度区间,余震基本发生在M6.3和M5.8级地震震源上部. 依据余震密集区展布范围,推测本次康定地震的震源体尺度长约30 km、宽约4 km、深度范围约6 km. M6.3级主震震源附近的余震稀疏区可能是一个较大的凹凸体（asperity）,在主震中能量得以充分释放. （3） 最初3天的余震主要分布在M6.3级地震NW侧;而M5.8级地震之后的余震主要集中在其震中附近. M6.3级地震以及最初3天的绝大部分余震发生在倾角约82°近直立的NW走向色拉哈断裂上;M5.8级地震与其后的多数余震发生在?

英文摘要：

On 22 Nov. 2014, an M6.3 earthquake hit Kangding County in Sichuan Province, southwestern China. 3 days later, another M5.8 earthquake occurred in the same region, about 10 km southeastwards from the epicenter of the M6.3 mainshock. Both earthquakes were on the NW-striking Xianshuihe fault zone where no M≥6.0 earthquakes were reported after the 1982 M6.0 Ganzi event. From the relocated aftershock distribution and focal mechanism solutions, we aim to analyze the seismogenic structure of the 2014 M6.3 Kangding earthquake sequence. Along with the analysis on the characteristics of the strong earthquake ruptures and the spatial distribution of the relocated small earthquakes, we will further discuss the future strong-earthquake risk between Daofu and Kangding on the central segment of the Xianshuihe fault zone.Based on the digital waveform data from China National Seismic Network and Sichuan Regional Network, the Kangding earthquake sequence was relocated by a multi-step locating method developed by Long et al. The focal mechanism solutions and the centriod depths of the M6.3 and M5.8 earthquakes were inverted simultaneously by the gCAP （generalized Cut and Paste） moment tensor inversion method. The spatial-temporal distribution of the M≥6.5 strong earthquake ruptures since 1725 and the focal depth distribution of relocated small earthquakes from Jan. 2001 to Oct. 2014 along the central-southern segment of the Xianshuihe fault zone were used to identify the potential seismogenic region of the next strong earthquakes on the segment between Daofu and Kangding.The epicentral relocation of the M6.3 mainshock is at 101.69°E、30.27°N, and its initial rupture depth is about 10 km, while the centroid depth is 9 km; the relocated M5.8 earthquake is at 101.73°E、30.18°N with the initial rupture depth at about 11 km and the centroid depth of 9 km. The moment tensor solutions from gCAP method show that the two events are dominated by the double-couple component. The parameters of the best double-couple solutions ar