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SN向小江断裂带与NW-NWW向曲江-石屏断裂带是云南地区两个相邻的活动断裂系统及强震发生带.为了了解它们的相互作用及其可能对地震发生的影响,基于活动构造、历史地震、重新定位的小震、GPS站速度与震源机制解等资料进行综合分析,结果表明:(1)小江断裂带西盘(川滇块体)的主动向南运动对曲江-石屏断裂带具有长期强烈的作用;后一断裂带以右旋走滑/剪切-横向缩短/逆冲变形的方式吸收与转换前一断裂带西盘的向南运动.(2)小江断裂带的现代左旋走滑/剪切变形速率由其北、中和中-南段的10～8mma-1减小到南段的4mma-1,速率减小的部分由曲江-石屏断裂带及其附近地区以逆-右旋走滑断层作用和分布式的右旋剪切与横向缩短变形进行调节.(3)小江与曲江-石屏断裂带的构造动力学关系还表现在它们地震活动的紧密关联上:1500～1850年期间小江断裂带及其以北的则木河断裂带完成了一个长达351a的强震、大地震发生序列,显示出应变逐渐加速释放、M≥7事件间隔逐渐缩短、大释放集中在序列中-后期等特征;作为对于这一序列的响应,曲江-石屏断裂带在滞后88a后,发生一个长达383a(1588～1970年)、具有相同加速释放与时间进程特征的强震与大地震序列.(4)至今,小江断裂带已有177a未发生M≥7地震,应注意并进一步研究该断裂带未来的强震与大地震危险性.
SN to Xiaojiang fault zone and NW-NWW to Qujiang-Shibing fault zone are two adjacent active fault systems and strong earthquake occurrence zones in Yunnan Province.In order to understand their interaction and their possible impact on earthquakes, The results show that: (1) The active southward movement of the west plate of the Xiaojiang fault zone (Sichuan-Yunnan block) - The Shiban fault belt has a long-term strong role; the latter fault zone absorbs and transforms the southward movement of the western fault of the former fault zone in the manner of dextral strike-slip / shear-lateral shortening / thrust deformation. (2) Xiao Jiang The modern left-lateral strike-slip / shear deformation rate of the fault zone decreases from 10 ~ 8mma-1 in the north, middle and mid-southern segments to 4mma-1 in the southern segment, and the rate of decrease decreases from Qujiang-Sheping fault The belt and its vicinity are controlled by reverse-right-lateral strike-slip faults and distributed right-lateral shear and lateral shortening deformation. (3) The tectonic dynamics of Xiaojiang and Qujiang-Shibing fault zones are also reflected in their The close correlation of seismicity: the Xiaojiang fault zone from 1500 to 1850 and its northward A series of strong earthquakes up to 351a have been completed in the river fault zone. The sequence of large earthquakes shows that the strain is acceleratingly released, the interval of M≥7 is gradually shortened, and the large release is concentrated in the mid- and late-stage sequences. As for this sequence After the lag of 88a, a sequence of strong earthquakes and large earthquakes with the same accelerating release and time-history characteristics occurred for 383a (1588 ~ 1970). (4) So far, the Xiaojiang fault zone There have been no M ≥ 7 earthquakes in 177a, and the future strong earthquakes and earthquakes in the fault should be studied and further studied.