鲜水河断裂带活动期次和滑移特性微观标志的识别

在鲜水河断裂带万木卡等地采集的第四纪形成并遭受变形的石灰华标本显微观测中,发现多期粘滑和蠕滑交替变形的证据;在该断裂带1923年炉霍、道孚间71/4级地震和1973年炉霍雅德7.9级地震震中部位野外考察过程中发现,沿地震断裂面分布有定向排列的砾石和破裂.从这些最新活动断面上采集的变形物质定向薄片显微观测中同样发现与上述类似的微观变形标志.这些发现和标志对鲜水河断裂第四纪以来活动期次与滑移特性的识别及研究具有重要的参考价值.

Identification of Microscopic Indicators of Active Times and Sliding Behavior in Xianshuihe Fault Zone

In observation, under microscope, of Calcareous samples formed and deformed in the Quaternary in Wanmuka of Xianshuihe fault zone, evidences of times of deformation with stick-slip and creep-slip alternately were found. During field observation of the fault zone, gravel and rupture with arranged direction along the seismic-fault plane were found in location of epicenters of Luhuo-Daofu Ms 7.25 earthquake, 1923 and Luhuo Ms 7.9 earthquake, 1973). Such directional fabrics were found in microscopic observing of the directional slices, which were made from deformational material of samples from the new active plane. Obviously, there are important significance to identification and research of active period and times and sliding behavior in Xianshuihe fault zone since the Quaternary.