The Wenchuan earthquake occurred along the Longmenshan thrust fault belt. The Longmenshan central fault is the earthquake causing fault. The total rupture length along the Longmenshan central fault caused by the Wenchuan earthquake is about 270 km and the average vertical and horizontal displacement range from 1.0 m to 5.0 m,up to about 9.8 m in local parts. A lot of buildings were broken in the area where the ruptures passed through. In this paper,the authors report the investigation results of the vertical and horizontal displacements,as well as the width of rupture influenced zones which were confirmed by the geophysical survey methods,in different locations along the Longmenshan central fault. It is indicated that the influenced scopes of the earthquake ruptures mainly range from16 m to 60 m,and the relationship between the influenced scopes(D)and the vertical displacement(H)is obvious linearity,which can be expressed as: D=10.11H+16.0. Due to the Longmenshan central fault being a mainly thrusting fault,the influenced zone ratio between the hanging wall side and the foot wall side is generally from 3：1 to 2：1,which can help to determinate the safe distance for building site. On the basis of field investigation and using overseas experience for reference,the limit of the safe distance on the hanging wall side should be not less than 15 m,and that on the foot wall side should be not less than 10 m. This research work has important significance for safe site selection in Longmenshan region during reconstruction after the earthquake．

5.12汶川Ms8.0级地震沿龙门山中央断裂带形成长度约270km的地表破裂带,破裂带垂直和水平位移一般为1.0～5.0m,最大可达9.8m。在地表破裂带附近,建筑物破坏严重。笔者系统调查了龙门山中央断裂带地表破裂的垂直和水平位移以及地震地表破裂影响带宽度,并采用物探测试方法对部分影响带宽度进行了验证。统计结果表明,汶川地震地表破裂影响带宽度主要集中在16～60m,影响带宽度（D）与垂直位移（H）具有较好的线性关系,即D=10.11H+16.0。对于逆冲性质为主的地震地表破裂而言,上盘影响带宽度与下盘的比值一般为3：1～2：1,据此可确定地表破裂带上、下盘的避让带宽度。笔者根据现场调查并借鉴国外经验提出,上盘避让宽度下限一般不应低于15m,下盘避让宽度下限不应低于10m。本项研究对于汶川地震灾后重建场地选址具有重要的实际意义。 

Wenchuan Earthquake triggered landslides, rock collapses and debris flows at more than 15000 sites, which directly caused about 20,000 fatalities.There are more than 10,000 sites of potential geo-hazards, where an increase in slope collapses is mostly noticeable, which shows the earthquake has substantially abnormal actions on steep slopes in the mountains. In particular, the amplifications at mountain peaks is extremely evident. A comprehensive analysis of quake lake volumes, landslide dam heights and their debris compositions and structures was carried out. An assessment on the 33 landslide dames of dam heights great than 10 m formed by the earthquake was further conducted. Consequently, the landslide dams were classified into four types of the dam burst potential : extremely high, high, intermediate and low. The sliding beds of the landslides induced by the earthquake usually have non-continuous flat sliding beds. "Sharp point collision" is a common and major characteristic. The sliding beds can be classified into spoon-shaped, raised-shaped and staircase-shaped. Site investigations demonstrate that the vertical vibrations in buildings destroyed by the earthquake adjacent to the landslides were evident. The landslides have three stages: throwing out of ground shocking, collision and collapsing and broken, and high-speed sliding flow. During the high-speed sliding flow, three effects were occurring: (1) high-speed air-bed effect, landslide debris were comprised with larger rock blocks and soils, had enough thickness and the flying distance of 1 to 3 km. (2) Broken debris flow effect, collision broken soils and rocks were in a flowing state, especially they contained abundant water, forming long distance flow sliding. (3) Shovel and scraping, huge collision forces induced collapse of rocks at lower portion, which formed new landslides and collapses, however, their thicknesses are not large and the sliding beds were non-smooth and irregular. The two landslides at western Beichuan county and Dongheko of Qingchuan county were analyzed in detail. They are used as examples to analyze the mechanism of the high speed and long distance sliding and hazard formation of earthquake landslides. The landslide at western Beichuan county buried 1,600 people and destroyed several hundreds houses and buildings, which is the severest landslide disaster triggered by the earthquake and is a rear event in the world. The Donghekou landslide at Qingchuan: Debris flow is a typical high speed and long distance landslide triggered by the earthquake. Its distrace is about 2,400 m. Its high-speed debris flew to the left bank of Qingjiang river and formed landslide dam, resulted 7 villages buried and about 400 fatalities.

汶川地震触发了15000多处滑坡、崩塌、泥石流,估计直接造成2万人死亡。地质灾害隐患点达10000余多处,以崩塌体增加最为显著,反映出地震对山区高陡斜坡的影响差异性非常大,在山顶上的放大作用非常显著。通过综合分析堰塞湖库容、滑坡坝高以及坝体物质组成和结构,对地震形成的33处坝高大于10m的滑坡堰塞湖进行了评估,划分出极高、高、中和低4种溃决危险。汶川地震滑坡滑床往往不具连续平整的滑面,"尖点撞击"是极震区滑坡的一大共性,可以分为勺型滑床、凸型滑床和阶型滑床等类型。据实地调查,滑坡附近震毁建筑物垂向震动非常明显,具有"地震抛掷"—"撞击崩裂"—"高速滑流"三阶段特征。在高速滑流中,发生3种效应:(1)高速气垫效应,滑坡体由较大块石和土构成,具有一定厚度,飞行行程可达1~3km;(2)碎屑流效应,撞击粉碎的土石呈流动状态,特别是含水丰富时,形成长程流滑;(3)铲刮效应,巨大撞击力导致下部岩体崩裂,形成新滑坡、崩塌,但是,其厚度不大,滑床起伏不平。本文以北川城西滑坡和青川东河口滑坡为例,分析了地震滑坡高速远程滑动及成灾机理。北川县城城西滑坡导致1600人被埋死亡,数百间房屋被毁,是汶川地震触发的最严重的滑坡灾难,举世罕见。青川东河口滑坡—碎屑流是汶川地震触发的较为典型的高速远程复合型滑坡,滑程约2400m,高速碎屑流冲抵清江河左岸,形成滑坡坝,致使7个村庄被埋,约400人死亡。

Wenchuan Earthquake occurred in the Longmen Mountain region, which geologic environment is very weak, and the earthquake with high magnitude, large energy, long duration and other characteristics. Wenchuan Earthquake directly induced thousands of rock fall and collapses. Some unique kinetics characteristics of these collapses have been found during the earthquake. Based on lots of collapse site investigations around Wenchuan area and combined with the characteristics of construction and slope broken patterns, the paper represents the kinetic characteristics of cracking, horizontal throwing and debris flows triggered by earthquake. It may provide some new clues to attribute the research on the causes of strong earthquake.

5.12汶川大地震发生于地质环境条件异常脆弱的龙门山地区，加上地震震级高、释放能量大，持续时间长等特点，汶川地震不仅直接诱发了数以万计的崩滑地质灾害，且表现出非常独特的动力学特征。在对汶川地震灾区崩滑灾害进行大量调查的基础上，结合建构筑物和斜坡岩体在地震过程中的变形破坏特点，本文从地震动力学和斜坡变形破坏成因机理的角度，揭示了汶川地震诱发的大型崩滑灾害具有震裂溃屈、临空抛射和碎屑流化等独特的动力学特征，为强震诱发地质灾害成因机理研究提供了新的认识。

In order to analyze the intensity and influence of landslides triggered by the great Wenchuan earthquake,a central idea in this paper is to focus on the first 3 extreme landslide events among the first 10 landslides with the largest volume,the longest sliding runout,the most serious hazard and the largest landslidedammed lake. The followings are revealed: (1)the extreme landslides are mainly distributed along the Longmenshan central fault and in the areas with high intensity of Ⅹ-Ⅺ;  the strong vibration force,the main propagation direction of earthquake and the NE expansion of seismic fault are the major reasons for the initiation of extreme landslide events; (2)generally,the first 10 landslides both have the largest volume and the longest sliding long runout,among them,the Daguangbao landslide,located at Anxian county,Mianzhu city,is the first one,with the volume of 742 million m3 and the sliding long runout of 35 km;  the second one is the Wenjiagou landslide in Qingping county,Mianzhu city,with the volume of 150 million m3 and the sliding runout of 42 km. The above two landslides are all rare rapid and long runout landslides with high energy in the world; (3)the first 10 catastrophic landslides totally caused 3751 deaths,and over 100 deaths are due to individual event,with the maximum of 1600; (4)the first 10 landslidedammed lakes with potential risk had threatened the lives safety for hundreds of thousands of people;  among them,the Tangjiashan dammed lake is the largest one,which had imperiled 03 million peoples life of Mianyang city;  fortunately,timely measures such as artificial excavation had been taken for removing of potential risk．

  为了分析汶川地震诱发滑坡灾害事件强度和影响,本文以汶川地震诱发滑坡极端事件为线索,在统计分析前10个规模最大、位移最远、危害最重及最大滑坡堰塞湖分布特征的基础上,重点研究前三甲极端滑坡事件的简要特征,初步揭示： (1)汶川地震诱发的极端滑坡事件主要沿龙门山中央断裂（映秀—北川断裂带）和Ⅹ-Ⅺ高烈度地段分布,强震的振动力、地震主传播方向和发震断裂NE向扩展作用是启动极端滑坡事件的主要原因；  (2)规模最大的前10个滑坡和距离最大的前10个高速远程滑坡具有很好的重合特征,两者都反映汶川地震诱发的高能量滑坡事件； 其中,规模最大的绵竹市安县大光包滑坡,初步估算体积约742×108m3,最大运动距离达到35km,距离排名第二； 距离最大的绵竹文家沟高速远程滑坡,初步估算最大位移为42km,其体积约15×108m3,规模排名第二,这两个滑坡都属于世界上罕见的大型高能量高速远程滑坡；  (3)前10个最大的灾难性滑坡事件,累计导致3751人死亡,单个滑坡引起的人员死亡超过100人,最多的达到1600人,属于世界上罕见的灾难性滑坡事件；  （4）潜在危险性最大的10个滑坡堰塞湖,曾经威胁几十万人的生活安全,其中,最大的北川唐家山滑坡堰塞湖,曾经威胁下游绵阳市30万人的生活安全,这些滑坡堰塞湖都及时采取人工开挖措施排除了潜在危险。

The relationship between active fault zone and large-scale landslides is a major issue on which people always concern. Based on field investigation of active fault zones and large-scale landslides induced by Wenchuan Ms 8.0 earthquake，the geological setting for large-scale landslides initiation in the Longmenshan active fault zones is documented，and the characteristics of distribution，shape，initiation and segmentation，as well as their influential factors，are summarized. Taking the Xiejiadianzi landslide-debris flow near the central Longmenshan fault zone as an example，simulations of the processes of landslide starting and fast slipping have been carried out by the discrete element method(DEM). It is thought that the disaster result of a rapid and long run-out landslide are dominated by the starting style，debris flying route and dumpling features. This research provides important information for the realization of the relationship between the fault movement and the formation of large-scale landslides，as well as prediction of the disaster result caused by earthquake landslides.

活动断裂带与大型滑坡之间的关系一直是人们关注的热点问题。通过汶川Ms8.0级地震活动断裂和大型滑坡调查，阐述龙门山活动断裂带大型滑坡形成的地质背景，总结活动断裂带大型地震滑坡的分布特征、形态特征、启动特征和分段特征及其相关影响因素。基于野外调查资料，以龙门山中央断裂带谢家店子滑坡为例，采用离散元方法模拟分析滑坡的启动和快速运移过程，提出高速远程滑坡的致灾后果决定于启动方式、飞行路径和堆积特征3个方面。本项研究对于认识断裂活动与大型滑坡之间的关系以及滑坡成灾后果预测具有重要的指导作用。

From May 13 to 27, 2009,the seismic responses of a slope during four aftershocks of the 2008 Wenchuan Earthquake were monitored with the 941B ultralowfrequency vibrometer and G01 generalpurpose instrument. The slope located at Wei Ganliang in Qingchuang county. The microseismic monitoring shows that relative to the 805 m elevation at the Wei Ganliang Mountain,the measured peak accelerations of ground motion at the 875 m elevation in the horizontal EW direction and vertical direction had the tendency of reduction. However,the measured peack accelerations in the horizontal NS direction had a significant multiplier effect. The magnification was up to 7 to 8 times. The main frequency of the amplitude spectrum focused on the low frequency range between 20 and 40 Hz. Analysis shows that the epicenter located on the north side of the NEE striking QingchuanPingwu fault. Along the direction of seismic wave propagation,the slope has significant an amplification effect．

本文采用941B型超低频测振仪及G01通用数采仪,自2009年5月13～27日,在青川县桅杆梁监测到4次余震。对山体斜坡高程805m和875m的余震地震动峰值加速度响应监测结果分析表明：相对于805m高程, 875m测点地震动峰值加速度在水平东西向以及垂向均呈减小趋势,而在水平南北向体现显著的放大效应,放大系数可达7～8倍,其FFT主频值主要集中为2～4Hz低频值。分析表明,所监测的微—有感地震震中位于测点北侧的青川断裂上,沿地震波传播方向斜坡体具有显著放大效应作用。

Over 15,000 landslides were triggered by the Wenchuan Earthquake along the Main seismic fault and back fault of the Longmen Mt. tectonic belt.  The area density of landslide coverage, i.e., the ratio of the landslide distribution and total area, is greater than 50 % in average and 70% in maximum along the Yingxiu-Gaochuan-Chenjiaba-Nanba of the main seismic fault. The enormous loosen rock masses  easy for occurring landslides and debris flows will seriously threat the reconstruction and living, especially, during raining seasons.  The largest landslide triggered by the Wenchuan Earthquake is located at the Daguangbao, Anxian County, of the main seismic fault. The volume of the Daguangba landslide is 1.1 billion m3, and 4,500 m long from scarp to toe, 2,800 m long, 1,700 to 2,200 m wide and 200 m in average thickness, and 580 m in max thickness for accumulation. It is also the maximum volume of single landslide in China.    Much differences with other conventional landslides, the sliding surfaces  are common incomplete and discontinued, and the exits were unclear in the epicenter area of the Wenchuan Earthquake,  which illustrates the upper rock mass was strongly vibrated and separated, then thrown and crushed with the bedrock. The five patterns of the landslides are classified as staircase-shaped, convex-shaped, bowel-shaped, slump (vibrated-expansive)-shaped and huge rock-stone in a broad sense. The strong ground motion records and destroyed house cases present that the vertical seismic load is dominated within the epicenter area, i.e., the vertical is greater than the horizontal of seismic load. It provides an explanation why lots of landslides experienced the processes of broken-thrown-crushed-high speed debris flow.

汶川地震诱发的15000多处滑坡明显受地震断裂控制，主要沿龙门山主中央断裂带和后山断裂带展布，沿龙门山主中央断裂带汶川映秀—安县高川—北川陈家坝—平武南坝一线，滑坡面密度大于50%以上，最大可达70%。沿断裂带形成了大量的松动山体，在暴雨期间极易发生滑坡、泥石流灾害，对灾后重建构成严重威胁。据初步调查，汶川地震触发的体积最大的滑坡是位于主中央断裂带上的安县高川大光包滑坡，滑动距离长4500m，滑坡堆积体长2800m，宽1700~2200m，最大厚度达580m，若以平均厚度200m计，体积达11亿m3为我国已发生的单体滑坡之最。与常见滑坡明显不同的是，汶川地震极震区滑坡的滑床往往不具连续完整的滑面，剪出口滑坡特征不明显，呈现明显的“尖点突起”或“边缘突出”特征，反映出上部滑体被地震力振动解体，甚至抛掷后与下部滑床边缘发生撞击。以阶型滑坡、凸型滑坡、勺型崩滑、座落型（振胀型）滑坡和巨大滚石5种类型最为典型。根据强震地面运动纪录和大量实例调查表明，在汶川地震极震区，触发滑坡的地震竖向力作用是非常明显的，大量滑坡经历了初始斜坡（风化碎裂岩体）——地震抛掷——撞击崩裂——高速滑流的作用过程。

The Daguangbao gigantic rockslide is located on the Gaochuan village,Anxia county.It is the hugest landslide triggered by the Wenchuan 8.0 earthquake on May 12 of 2008.This paper uses four periods of remote sensing data with high resolution before/after the earthquake and ground surveying and mapping data to analyze the basic features of the Daguangbao rockslide.The basic features include the accumulation and movement zoning,the sliding surface and exiting,and the volume.The Daguangbao gigantic rockslide is classified into sliding source,back depression,main bedrock accumulation,down-stream accumulation,up-stream accumulation and front lobe.The main bedrock accumulation remained a structure of parent layered limestone rockmass with slight separation that is 1, 100m long, 490m wide, 215m average thick and 464millions m 3 in the volume.The sliding direction and boundary are outlined according to the compared result before/after topography,geomorphology,and mining adit,waste ore material and sheds.The bedrock sliding distance is about 1750m.A digital elevation model with the scale of 1 to 5000 before/after earthquake is established to calculate the area and the thickness of the rockslide accumulation.With the AutoCAD,a 3D entity model of the sliding surface is also established.The result shows the whole Daguangbao gigantic rockslide is 4300m long, 3500m wide and 550m thick in the maximum.The debris volume is about 1.15~1.2 billion m 3 .It is the hugest landslide not only in China,but also in the world in recent hundred years.

大光包滑坡位于四川省安县高川乡,是汶川 Ms 8.0级地震触发的规模最大的巨型滑坡。本文采用震前和震后高分辨率遥感数据源,对大光包滑坡滑动前后进行了4期遥感图像对比解译和分析,结合现场调查和地面测绘,对滑坡分区、滑面形态、剪出口位置及滑坡体体积进行了初步研究。将滑坡划分为滑源区、滑坡洼地区、主滑体堆积区、下游堆积区、上游堆积区和前缘堆积区,其中,主滑坡堆积区基本保持了母岩原有结构形态,其岩层产状与基岩大体一致,未明显解体,出露长1100m,宽490m,平均厚215m,体积达4.64×10 9 m 3 。对比了滑动前后的地形、地貌,以及原矿硐、矿渣、工棚等的位置变化,确定了滑坡边界、滑动方向,滑动距离达1.75km。本文建立了大光包滑坡区1: 5000地面数字高程模型(DEM),获得了滑坡堆积区平面分布面积及最大堆积厚度,采用AutoCAD软件分别建立了大光包滑坡滑动前后及滑面的三维实体模型,计算出大光包滑坡最大纵长约4.3km,横宽约3.5km,最大厚度约550m,体积约为11.52~11.99×10 9 m 3 ,不仅是我国,也是全球近百年来发生的规模最大的滑坡之一。

The complicate earthquake dynamic response is simulated with FLAC3D that is much different with simple/homogeneous slope due to poor amplitude effect along the height. For the horizontal acceleration response，the front of the landslide has greater vibrating frequency and amplitude，that is easier to trigger the slide along the inclined layer. For the vertical acceleration response，the back of the landslide has greater amplitude of vibration，and as three times as the absolute value of the acceleration in the front，that is easier cracking，fragmenting or even throwing rock mass. In light of the earthquake dynamic response and movement，the landslide accumulation and source are zoned as follows：(1) the lower inclined bedding sliding accumulation，which distributed in the East and dammed a tributary named the Huangdongzi；(2) the upper avalanche accumulation，which distributed in the Northwest and the North that overlay the North margin of previous sliding accumulation with belt-like；(3) the back cliff and talus，in which lots of cracks in the cliffs shows the tensive failures during the vibration；and lots of talus masses show gravity processes after the earthquake；(4) inclined bedding sliding surface and striation，which distributed at the back of the lower inclined bedding landslide. Enormous large-scale striation belts show the moving direction to North that is as same as the tendency of the layer.

运用FLAC3D模拟大光包滑坡变形失稳特征，并输入距离滑坡约4.3 km的清平台站强震加速度三向记录，结果表明：其地震动力响应较为复杂，受控于斜坡形态、岩体(地质)结构及地震强度和振动持时等因素，在水平加速度响应方面，前缘滑坡更为明显，地震动频率更高，振幅更大，利于前缘的顺层失稳滑动；在竖向加速度响应方面，后缘滑体的振幅更大，竖向加速度(绝对值)数倍于水平加速度，利于拉裂、振碎解体和抛掷失稳。大光包滑坡与简单均值结构的边坡地震动力响应特征不完全一致，随高程、坡度放大的趋向性和节律性不明显。结合地震动力响应和运动特征，对滑坡堆积和滑源进行概化分区：(1) 下部顺层滑坡堆积区，是滑坡的主堆积区，分布于滑坡东侧，堵塞黄洞子沟；(2) 上部崩滑堆积区，分布于滑坡西北、北侧，具有明显的带状特征；(3) 后缘陡壁及倒石堆区，侧缘拉裂边界，近直立不规则凹凸状断壁，分布多组张拉裂隙，说明受陡倾角张性裂隙控制，表现为张性破坏特征，陡崖下部分布大量倒石堆，呈串珠状分布，以碎块石为主，岩性与后缘及北侧陡壁岩体一致，系地震后的重力调整所致；(4) 顺层滑面及擦痕区，在滑面上分布大量与岩层倾向相同的擦痕，说明顺层滑坡在后部具有向北方向偏转滑动的特征。

The rapid assessment method on seismic landslide hazard based on simplified Newmark displacement model is preliminarily developed, in Wenchuan M s 8.0 earthquake severely afflicted 11 counties. With the real-time earthquake ground motion parameters, empirical engineering geology lithology formations, topographic slope data, the module of seismic landslide hazard rapid assessment is produced based on ArcGIS spatial data modeller tools. Static safety factor F s and critical acceleration a c of regional shallow saturated rock and soil mass slope are calculated, according to which seismic landslide susceptibility is assessed. The Arias intensity of Wenchuan earthquake and regional landslide displacement D N distribution are calculated with empirical formula, based on which rapid assessment of seismic landslide hazard in Wenchuan earthquake severely afflicted area is realized. The assessment results can be reference for emergency response decision-making. It is indicated that tens of catastrophic landslides are almost totally located in extreme high-high hazard zone, which within both sides about 20km of Longmenshan central fault belt through comparing the seismic landslide investigation and assessment results. The comparing result indicates the well reliability of assessing model. Meanwhile, the limitation is also analyzed that local assessment result is inaccurate due to poor spatial data accuracy and update. Some improvement suggestion is provided.

以汶川 M S 8.0级地震重灾区的11县市为例,初步提出了基于简化Newmark位移模型的地震滑坡危险性应急快速评估方法。利用汶川地震即时地震动参数、工程地质岩性经验分组及地形坡度数据,借助ArcGIS空间数据建模工具编制了地震滑坡危险性快速评估流程模块。计算了区域浅表层饱和岩土体斜坡的静态安全系数 F s 、临界加速度 a c ,并借此分析了地震滑坡易发性。利用经验式获得了汶川地震Arias强度和区域滑坡位移 D N 分布,实现了汶川地震重灾区地震滑坡危险性的快速评估,为应急救灾决策提供了参考。通过对比评估结果和震后滑坡调查成果,可知数十处灾难性滑坡绝大部分位于-高危险区的龙门山主中央断裂带两侧约20km地带中,显示了评估方法的可靠性; 同时,分析指出了空间数据精度及更新不足导致局部评估结果欠佳的局限性,并提出了改进建议。

It was 3 years since the Wenchuan earthquake.A lot of domestic and foreign scholars have conducted a great deal of work on the development and distribution patterns,formation mechanisms and prevention strategies of the geohazards triggered by the Wenchuan earthquake,and have published a lot of research results.Since the frequency and scale of increased markedly,especially in 2010,many researchers are beginning to pay close attention to the occurrence rules,activity trends and duration of geohazards triggered by rainfalls after the Wenchuan earthquake.This paper collected the data pre-and post-earthquake,and analyzed the characteristics and occurrence rules of major geohazards triggered by rainfalls in the last 3years in the Wenchuan earthquake area.Based on this,the duration,activity trends and high risk areas of geohzards in the Wenchuan earthquake areas were analyzed.The preliminary study results indicate geohazard activity in theWenchuan erathquake area will keep still intense in future 20-25 years.In this period of time,geohazard activity level appeared to decline in shock with the cycle of every four or five years.After that,the geological condition will be gradually stable.The high geohazards risk areas will be mainly distributed along the Yingxiu-Beichuan fault,especially in the sections of Genda-Yingxiu in Wenchuan county,Xiaoyudong in Pengzhou county,Hongbai,Shifang county-Chaping,Anxian county,Leigu-Chenjiaba in Beichuan county and Donghekou-Woqian in Qingchuan county.

汶川地震过去3a了。3a来,大量的国内外学者对地震灾区地震地质灾害的发育分布规律、形成机理及防治对策给予了高度关注,发表了大量的研究成果。人们在关注同震地质灾害的同时,更对地震灾区今后地质灾害的发生规律及演化趋势、持续时间倾注了极大的关心,因为震后连续3a,尤其是2010年,灾区地质灾害的频率和规模均出现较震前显著增大的现象。本文收集整理了震前和震后灾区地质灾害的数据资料,尤其研究了震后3a灾区重大地质灾害的特点和发生规律,在此基础上,分析了震后灾区地质灾害可能的持续时间、演化趋势以及高风险区的范围。分析和研究结果认为,震后汶川地震灾区的地质灾害将持续20~25a; 在这段时间内,地质灾害将以4~5a一个高峰为周期,呈震荡式的衰减下降,并最终恢复到震前的水平。震后地质灾害的高风险区将出现在耿达-映秀、小鱼洞、红白-茶坪、擂鼓-陈家坝和青川东河口-窝前这5个地段上。