论文部分内容阅读
2013年8月28日和8月31日在云南迪庆藏族自治州德钦县、香格里拉县与四川甘孜藏族自治州得荣县交界地区发生M_S5.2、M_S5.9地震,两次地震相距约10 km,期间又发生多次强余震,该地震的发震构造为川滇菱形块体西北边界的德钦-中甸-大具断裂带。我们通过对震中区断裂的野外地质调查,结合前人对该断裂第四纪活动研究方面的成果,对德钦-中甸-大具断裂带震中区附近的活动性、运动特征等进行了揭示和探讨。野外调查揭示该断裂在瓦卡镇至推改村沿线断裂在近地表为高角度逆冲性质,这与前人对香格里拉-得荣地震群序列的震源机制解研究揭示的该地区拉张应力环境不太协调,也与断裂整体的右旋走滑运动性质不太一致,这可能是由于走滑断裂在走向转变处于近地表形成的局部效应,并不能代表断裂带总体的运动性质。德钦-中甸-大具断裂为全新世活动断裂,总体表现为以右旋走滑为主的运动性质。
On August 28, 2013 and August 31, 2013, M_S5.2 and M_S5.9 earthquakes occurred in the border areas of Deqin County, Diqing Tibetan Autonomous Prefecture in Yunnan Province and Shangri-La County in Ganzi Tibetan Autonomous Prefecture, Sichuan Province. The two earthquakes were about 10 km apart, During this period, several strong aftershocks occurred again. The seismogenic structure of this earthquake was the Deqin-Zhongdian-Dadu fault zone on the northwestern boundary of the Sichuan-Yunnan rhombic block. Based on the field geological survey of the epicenter area faults and the achievements made by the predecessors in the study of the Quaternary activity of the fault, we revealed the activities and movement features near the epicenter of the Deqin-Zhongdian-Dadu fault zone And explore. The field investigation revealed that the fault ruptured near the surface of the village along Huakai Village from Waka to Gaohushui in a high angle. This is in line with the previous study on focal mechanism solutions of the Shangri-La-Rong earthquake sequence. Which is not coordinated well with the whole nature of the right-lateral strike-slip movement of the fault. This may be due to the local effect of strike-slip faults on the near surface during the strike change and does not represent the overall movement of the fault. The Deqin-Zhongdian-Diantai fault is a fault of Holocene activity, which is generally characterized by the dextral strike-slip movement.