CAJ | 학술논문

青藏滇缅印尼歹字型构造体系是地质力学中最为典型的反“S”状（或“Z”状）旋扭构造体系，其中各构造部位之间在运动学与动力学方面具有密切的成生联系，并且现今活动性非常显著，属于典型的活动构造体系。梳理分析该构造体系中 M≥6．8历史大地震的活动状况发现，与其运动学方面的整体性与协调性相对应，其头部、中部与尾部之间的大地震活动具有明显的联动效应，即当头部与尾部发生大地震序列后不久（大致为几个月、几年或十几年尺度），中部（尤其是我国的川滇强震区）随即也会发生大地震。但在1997年以来的最近一次大地震活动序列中，构成该构造体系中段的川滇地区却出现了长达15年之久的“异常平静”状态，这无疑意味着该区未来发生大地震的危险性将显著增加。进一步结合西南地区川滇弧形旋扭活动构造体系研究的最新成果，依据活动断裂带上大地震危险性判定的离逝时间、地震空区和强震连锁反应等“三准则”，初步认为该区当前存在至少9个比较明显的大地震危险区带，包括：鲜水河-小江断裂带上的安宁河段、巧家段和南端的澄江-建水段，理塘-大理-瑞丽弧形活动构造带上的畹町断裂带和南汀河断裂带、滇西北裂陷带中的鹤庆-松桂断陷盆地区和程海-宾川断裂带期纳-宾川段，澜沧-景洪断裂带的景洪段，以及近南北向的保山断陷盆地和元谋断陷盆地。这一研究结果将有助于进一步全面认识我国西南地区当前的大地震形势，进而科学部署开展地震地质与地震预报预测工作。
청장전면인니알자형구조체계시지질역학중최위전형적반“S”상（혹“Z”상）선뉴구조체계，기중각구조부위지간재운동학여동역학방면구유밀절적성생련계，병차현금활동성비상현저，속우전형적활동구조체계。소리분석해구조체계중 M≥6．8역사대지진적활동상황발현，여기운동학방면적정체성여협조성상대응，기두부、중부여미부지간적대지진활동구유명현적련동효응，즉당두부여미부발생대지진서렬후불구（대치위궤개월、궤년혹십궤년척도），중부（우기시아국적천전강진구）수즉야회발생대지진。단재1997년이래적최근일차대지진활동서렬중，구성해구조체계중단적천전지구각출현료장체15년지구적“이상평정”상태，저무의의미착해구미래발생대지진적위험성장현저증가。진일보결합서남지구천전호형선뉴활동구조체계연구적최신성과，의거활동단렬대상대지진위험성판정적리서시간、지진공구화강진련쇄반응등“삼준칙”，초보인위해구당전존재지소9개비교명현적대지진위험구대，포괄：선수하-소강단렬대상적안저하단、교가단화남단적징강-건수단，리당-대리-서려호형활동구조대상적원정단렬대화남정하단렬대、전서북렬함대중적학경-송계단함분지구화정해-빈천단렬대기납-빈천단，란창-경홍단렬대적경홍단，이급근남북향적보산단함분지화원모단함분지。저일연구결과장유조우진일보전면인식아국서남지구당전적대지진형세，진이과학부서개전지진지질여지진예보예측공작。
There is a mega-tectonic system in south Asia,which is called South Asia “Z”shaped tectonic system in Lee’s geomechanics theory.Its range mainly involves Qinghai-Tibet,Yunnan,Myanmar and Indonesia. The present activity of the tectonic system is very prominent and controls many large earthquakes (M≥6. 8)distribution,so it is a typical active tectonic system.Based on recent studying on active faults and earthquake geology,we analyzed in detail the present activity and large earthquake events since 1320 A.D. along the active tectonic system.The studying results show that the consistency aspects of kinematics and large earthquakes chain reaction or domino effect resulted from active fault interaction are all very obvious along different structure segments of the mega-tectonic system.The interaction effect of large earthquakes is that the middle segment occurred immediately large earthquake events soon after (usually about few months or few years,and sometimes more than ten years)some large earthquakes occurred along the head of tail of the South Asia “Z”shaped mega-tectonic system.But during the latest large earthquake cycle since 1997 A.D.,the Sichuan-Yunnan constituting the middle segment of the tectonic system,which is a typical active province of large historical earthquakes in west-south China,appeared aseismic period of large earthquakes sustainable more than ten years after many large earthquakes occurred along the head and tail segment of the tectonic system.The long large earthquakes quiescence occurred in middle segment is obviously incompatible with the interaction effect of large earthquakes of the South Asia “Z”shaped tectonic system,and implies that there is very high large earthquake hazard in the near future at the middle structure segment.Based on the newest active faults studying on Sichuan-Yunnan arc rotation-shearing active tectonic system combining with three fundamental criterions of seismic hazard assessment,including elapsed time after large earthquake events,seismic gap and chain reaction or domino effect of large earthquake events,we suggest that there are 9 large earthquake high hazard areas or belts in the Sichuan-Yunnan arc active tectonic system,including:Anninghe segment of the Xianshuihe-Xiaojiang fault zone, Qiaojia segment of the Xianshuihe-Xiaojiang fault zone,the southern section of the Xiaojiang fault of the Xianshuihe-Xiaojiang fault zone,Heqing-Songgui graben basin and the Chenghai-Binchuan fault in rifting zone of the west-north Yunnan,the seismic gaps along the Wanding fault and Nantinghe fault,the east-south segment of the Lancang-Jinghong fault zone,Yuanmou graben and Baoshan graben.The new seismic hazard assessment results are helpful to understand present large earthquake trend on the Shichuan-Yunan active tectonic system of west-south China.