地球学报
地毬學報
지구학보
Acta Geoscientia Sinica
2015年
6期
760-769
,共10页
黄小龙%吴中海%赵小艳%吴坤罡%黄小巾%杜锦锦
黃小龍%吳中海%趙小豔%吳坤罡%黃小巾%杜錦錦
황소룡%오중해%조소염%오곤강%황소건%두금금
盈江地震%发震断层%地震烈度%苏典断裂%腾冲地块
盈江地震%髮震斷層%地震烈度%囌典斷裂%騰遲地塊
영강지진%발진단층%지진열도%소전단렬%등충지괴
Yingjiang earthquake%seismogenic fault%seismic intensity%Sudian fault%Tengchong block
2014年5月云南省盈江县先后发生MS5.6、MS6.1地震,为确定它们的发震构造及其所反映的区域活动构造格局,笔者围绕该区开展了地震烈度调查、活动构造遥感解译、地质构造及构造地貌野外调查、震源机制解及余震分布资料分析等工作。调查与分析表明,两次地震的宏观震中均位于盈江县勐弄乡麻栗坡村附近,但发震断层明显不同。前者为NE走向左旋走滑的昔马—盘龙山断裂,后者为近SN向右旋走滑的苏典断裂。历史地震资料显示,盈江地区的地震活动多以5~6级的中-强震为主,并具有明显的群发性和沿SN向断层迁移的特征。在实皆断裂及滇西内弧带的共同作用下,腾冲地块内以大盈江断裂为界,北部主要发育近SN向右旋走滑断裂,南部则以NE向左旋走滑断裂为主,其中近SN向断层晚第四纪活动性更强。
2014年5月雲南省盈江縣先後髮生MS5.6、MS6.1地震,為確定它們的髮震構造及其所反映的區域活動構造格跼,筆者圍繞該區開展瞭地震烈度調查、活動構造遙感解譯、地質構造及構造地貌野外調查、震源機製解及餘震分佈資料分析等工作。調查與分析錶明,兩次地震的宏觀震中均位于盈江縣勐弄鄉痳慄坡村附近,但髮震斷層明顯不同。前者為NE走嚮左鏇走滑的昔馬—盤龍山斷裂,後者為近SN嚮右鏇走滑的囌典斷裂。歷史地震資料顯示,盈江地區的地震活動多以5~6級的中-彊震為主,併具有明顯的群髮性和沿SN嚮斷層遷移的特徵。在實皆斷裂及滇西內弧帶的共同作用下,騰遲地塊內以大盈江斷裂為界,北部主要髮育近SN嚮右鏇走滑斷裂,南部則以NE嚮左鏇走滑斷裂為主,其中近SN嚮斷層晚第四紀活動性更彊。
2014년5월운남성영강현선후발생MS5.6、MS6.1지진,위학정타문적발진구조급기소반영적구역활동구조격국,필자위요해구개전료지진열도조사、활동구조요감해역、지질구조급구조지모야외조사、진원궤제해급여진분포자료분석등공작。조사여분석표명,량차지진적굉관진중균위우영강현맹롱향마률파촌부근,단발진단층명현불동。전자위NE주향좌선주활적석마—반룡산단렬,후자위근SN향우선주활적소전단렬。역사지진자료현시,영강지구적지진활동다이5~6급적중-강진위주,병구유명현적군발성화연SN향단층천이적특정。재실개단렬급전서내호대적공동작용하,등충지괴내이대영강단렬위계,북부주요발육근SN향우선주활단렬,남부칙이NE향좌선주활단렬위주,기중근SN향단층만제사기활동성경강。
Two earthquakes ofMS5.6 andMS6.1 occurred successively on May, 2014, in Yingjiang, Yunnan province. In order to determine their seismogenic structures and the regional active tectonic settings, the authors carried out field investigation of seismic intensity, remote sensing image interpretation, analysis of focal mechanism solutions and aftershock distribution. The results show that the macro-epicenters of two earthquakes were both located near the area of Malipo Village, Mengnong Township, Yingjiang County, but their seismogenic faults are different from each other. The former was associated with the NE-trending left-lateral strike-slip Xima-Panlongshan fault, whereas the latter occurred along the SN-trending right-lateral strike-slip Sudian fault. Historical seismicities were dominated by the earthquakes with magnitude 5~6 in the Yingjiang region, which clustered along the SN-trending fault. Under the combination effect of Sagaing fault and inner arc belt in western Yunnan, the north of Tengchong block bounded by Dayingjiang fault is mainly dominated by nearly SN-trending right-lateral strike slip faults, whereas the south is dominated by NE-trending left-lateral strike slip faults. The activity of nearly NS-tranding faults was relatively stronger in Late Quaternary.