CAJ | 학술논문

位于中国西南的小江(Xiaojiang)断裂带作为康定(Kangding)断裂带的南段,在青藏块体向SE方向挤出的过程中起着重要的作用.根据断错地貌以及这些断错地貌14C年代或热释光年代,推算了小江断裂带第四纪晚期的左旋走滑速率.小江断裂带可以分为3段,其中段由平行的两条断层组成.西支断层和东支断层的左旋走滑速率分别为7.0～9.0mm/yr和6.0～7.5mm/yr.简单相加,就可以推算出小江(Xiaojiang)断裂带总的左旋走滑速率为13.0～16.5mm/yr,与康定断裂带北段的鲜水河(Xianshuihe)断层的走滑速率大致相当,约等于康定(Kangding)断裂带中段的安宁河(Anninghe)断层及则木河(Zemuhe)断层的两倍.这个结果可能暗示了在康定断裂带中段,可能存在着其他断层以解消另外一半的滑动速率.最有可能的断层是位于康定断裂带中段以东几十公里的普雄河-布拖(Puxionghe-Butuo)断层.
위우중국서남적소강(Xiaojiang)단렬대작위강정(Kangding)단렬대적남단,재청장괴체향SE방향제출적과정중기착중요적작용.근거단착지모이급저사단착지모14C년대혹열석광년대,추산료소강단렬대제사기만기적좌선주활속솔.소강단렬대가이분위3단,기중단유평행적량조단층조성.서지단층화동지단층적좌선주활속솔분별위7.0～9.0mm/yr화6.0～7.5mm/yr.간단상가,취가이추산출소강(Xiaojiang)단렬대총적좌선주활속솔위13.0～16.5mm/yr,여강정단렬대북단적선수하(Xianshuihe)단층적주활속솔대치상당,약등우강정(Kangding)단렬대중단적안저하(Anninghe)단층급칙목하(Zemuhe)단층적량배.저개결과가능암시료재강정단렬대중단,가능존재착기타단층이해소령외일반적활동속솔.최유가능적단층시위우강정단렬대중단이동궤십공리적보웅하-포타(Puxionghe-Butuo)단층.
The Xiaojiang fault is the southern portion of the Kangding fault zone, which is a noticeable active fault in southwest China and plays an important role in the left-lateral extrusion of the Tibetan Plateau. We determined average slip rates of the Xiaojiang fault, on the basis of offset landforms that were precisely mapped and dated by radiocarbon or thermoluminescence methods. The Xiaojiang fault consists of two subparallel fault strands in its middle segment; the average left-lateral slip rates on the west and east strands were determined to be 7.0～9.0mm/yr and 6.0～7.5mm/yr, respectively. Thus, the total slip rate on the Xiaojiang fault amounts to 13.0～16.5mm/yr. This value is approximately equal to that on the Xianshuihe fault, the northern part of the Kangding fault zone, and about twice as high as that on the Anninghe and Zemuhe faults, the middle part of the Kangding fault zone. Our results suggest that there must be other active faults that accommodate the missing slip in the middle of the Kangding fault zone; the most probable candidate may be the Puxionghe-Butou fault zone located several ten kilometers to the east of the middle segment.0041, China[=4) Seismological Bureau of Yunnan Province, Kunming 65