摘要
结合前人研究结果和野外考察,发现1936年甘肃康乐6^3/4级地震的地表破裂带长14 km,走向NWW,主要由3小段（西段、中段和东段）呈右阶排列而成。地表破裂主要有地震陡坎、地裂缝等。西段长3.7 km,有新鲜的崩塌堆积;中段长4.4 km,有大规模的基岩崩塌,同震左旋位移和垂直位移分别为2.5 m和0.6 m;东段长约6 km,同震水平位移和垂直位移分别为1.5 m和0.3 m。同震变形以左旋走滑为主,兼具逆冲分量,最大地表垂直位错量（0.6 m）仅为水平位错量（2.5 m）的（1/4）。1936年康乐地震时崩落的岩块上零星生长着最大直径仅20-30 mm的丽石黄衣,部分无地衣生长,此次地震由围子山—大夏河断裂向东扩张所致。
Combined with the previous studies and the field surveys of Kangle M6^3/4 earthquake in 1936, we found that the length of surface rupture is about 14 km, the strikes of it is NWW. The surface rupture is mainly constituted of 3 segments （the western, the middle and the eastern segements） and exhibits a right-stepping arran- ging, and the rupture phenomena in extreme seismic zone are mainly earthquake scarp and ground fissures etc.. The western segment where the fresh rock falls accumulated extends about 3.7 km; the middle segment where huge scale rock falls extends about 4. 4 km, the coseismic left-lateral and uplift displacements in the middle segment is 2. 5 m and 0. 6 m respectively; the eastern segment extends about 6 km, and the coseismic horizontal and uplift offsets is 1.5 m and 0. 3 m respectively. The coseismic deformation caused by the earthquake is mainly left-lateral with thrust components, the maximum surface uplift dislocation （0. 6m） is one-fourth of horizonal component （2. 5m） . The falling rocks caused by Kangle M6^3/4 earthquake in 1936 have scattered distributed Xanthoria elegans with a maximum diameter about 20 - 30 mm, some falling rock without any lichens. The Kangle M6^3/4 earthquake is caused by the eastern-extension activity of Weizishan-Daxiahe Fault.
出处
《地震研究》
CSCD
北大核心
2015年第2期262-271,333,共10页
Journal of Seismological Research
基金
中国地震局地震预测研究所基本科研业务费(2013IESLZ07)资助
