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2019年6月10—13日,龙川县发生持续强降雨,导致全县境内发生大量滑坡、泥石流灾害,贝岭镇米贝村是三个重灾区之一。本文以贝岭镇米贝村6号沟发生的滑坡-泥石流链生灾害为研究对象,在野外精细化调查测量基础上,结合数值模拟分析与计算,对链生灾害特征与成灾机理展开研究。研究发现:①6号沟内共发育7处浅层土质小型滑坡,仅3号滑坡体与部分6号滑坡体转化为泥石流,构成泥石流主要物源,其余滑坡未构成持续性影响;②持续降雨下渗,坡体由非饱和向饱和状态转变,坡表形成连续饱和区,孔隙水压力的增加与孔隙水的软化促使土体强度降低,加之坡体饱和自重的增大,斜坡发生浅表层失稳破坏;③降雨的持续下渗与支沟沟源“漏斗状”地形下的地表汇水快速增大滑坡松散堆积体内的含水率,促使其物理性质发生变化,在重力势能下呈流态状启动、运动转化为泥石流。降雨结构影响滑坡-泥石流链生过程,前期降雨引发滑坡、后期降雨启动形成泥石流,滑坡与泥石流的发生表现出阶段性特征。研究成果有助于指导当地政府进一步开展滑坡-泥石流链生灾害的防灾减灾工作,也为该地区未来区域预警研究工作提供理论支撑。 相似文献
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该滑坡泥石流特征为,流域面积小,流程短,规模小,以坡面型为主,多由滑坡崩塌转化而来,发生频率低,突发性强,危害大。文章揭示在植被覆盖的花岗岩地区,持续强降雨引发群发性浅层土质滑坡,在斜坡微凹处或小沟谷,易转化成泥石流,形成灾害链。对该类型滑坡泥石流特征及成因进行分析,为福建省乃至全国同类型滑坡-泥石流的防治提供经验。 相似文献
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2011年6月5日至6月6日,贵州望谟县发生连续强降雨,引发境内纳包沟泥石流灾害,给当地居民的生命和财产造成巨大损失。本研究着重分析了纳包沟泥石流的物源、地形和降雨因素,指出该地区降雨强度大,流域内30°～40°坡度范围比例最大,最有利于浅层滑坡的发育,滑坡进而为泥石流的暴发提供主要物源;进一步得出泥石流的特征和动力学参数,泥石流为稀性泥石流,最大洪峰流量25 m3/s,泥石流一次冲出固体总量约6 100 m3。该次泥石流的形成机理为浅层滑坡引起的滑坡型泥石流。针对纳包沟的特点,当地政府和居民都应高度重视并实施相应的生物和工程措施以预防泥石流的发生。 相似文献
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2016年7月6日晨0时40分左右,新疆喀什地区叶城县柯克亚乡六村发生特大滑坡泥石流灾害,造成重大人员伤亡和财产损失。本研究采用地面调查、访问和遥感解译方法,从滑坡、泥石流形成的地形地貌、地层岩性和水文气象条件着手,分析了滑坡特征与成因,泥石流形成条件、灾害链过程与致灾机理,并对未来本区滑坡泥石流的发展趋势进行了预测。现场调查表明:（1）位于西昆仑山北坡中高山区的六村与七村毗邻区域,在6日凌晨发生的大暴雨,触发了38处群发性浅层黄土滑坡,属蠕滑-拉裂机制,且部分大滑坡表现为远程滑坡-泥流特征;（2）这些滑坡体堆积在“V”形沟谷中形成堰塞坝,其中六村上游发育15处滑坡和2个滑坡堰塞坝,在持续降水和小型沟谷泥石流的作用下,滑坡坝发生串联式溃决而形成堵溃型泥石流,冲毁六村居民区和道路;（3）同时,该毗邻区域两侧存在超过227处的黄土滑坡变形体,未来在区域气候由暖干转向暖湿条件下,强降雨的极端气候事件会增多,若遭遇强降雨,研究区仍然会爆发滑坡-堰塞坝-溃决泥石流模式的灾害,其规模可能比“7·6”事件还大。建议深化本区浅层黄土滑坡变形机理、临界雨量及泥流运动机理等方面的深入研究,同时加强滑坡泥石流的监测和预测研究。 相似文献
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牛眠沟研究区位于2008-05-12汶川大地震线性震源的南端,受强烈地震力作用,区内山体遭受严重破坏,发生多处滑坡和泥石流灾害。根据已建立的暴雨滑坡、泥石流预测概念模型,暴雨滑坡、泥石流预测可视为判断滑坡形成的地质环境和确定触发滑坡的降雨特征。查明研究区地质环境及灾害特征,确定了产生滑坡、泥石流的必要地质环境因子,以数字滑坡技术获取这些因子数据,代入模型,即可评价研究区各处、各沟谷发生滑坡、泥石流的危险程度;与相似地质环境及气候条件进行类比,确定研究区触发滑坡、泥石流的降雨特征及降雨量阈值后,最终建立暴雨滑坡、泥石流预测模型。据此模型进行研究区暴雨滑坡、泥石流预测,实地验证表明滑坡、泥石流发生位置的准确率>90%。 相似文献
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钟立勋 《中国地质灾害与防治学报》2006,17(2):I0001-I0002
照片1伊犁州新源县别斯托别乡2005—05一04大暴雨诱发上覆黄七的基岩风化带发滑坡一泥石流灾害。滑坡体从高处(见云杉林后数处滑坡)发生后。转化为泥石流．造成3人死亡，掩埋羊群共302只，毁坏牧场，冲毁百年云杉及牧比的帐蓬、羊圈等照片3在花岗岩体上，覆盖黄土及残坡积物。2004 04一09巩留县萸乎尔乡遭遇一场大暴雨后．普遍发生浅层滑坡泥石流灾害。，山土发生滑坡后 转化为泥石流，居住在山上河流旁边的农牧民受到财产损失和人畜伤亡．照片2伊犁州巩留县莫乎尔乡遭遇2004一04—09暴雨引发滑坡泥石流灾害。黄土覆盖下的花岗岩风化带发生… 相似文献
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地震扰动区存在大量震裂松散坡体,在持续或者密集的降雨条件下极易转化为滑坡灾害。同时,滑坡又会给泥石流提供大量松散固体物质,增加泥石流的危险性。因此,在震区,灾害通常以"链"的形式出现,比单一灾种危害性大。为了更有效地对地质灾害危险性进行评价,笔者将滑坡、泥石流作为灾害链,综合地加以分析和研究。选择5·12汶川大地震中受灾严重的都江堰市白沙河流域的17条泥石流沟作为研究区,建立滑坡-泥石流危险性评价耦合模型,研究24 h不同降雨量条件下小流域滑坡泥石流危险性的变化。耦合模型包括了坡体稳定性评价模型,水文模型及以泥石流规模、发生频率、流域面积、主沟长度、流域高差、切割密度、不稳定斜坡比为评价因子的泥石流危险性评价统计模型。研究结果表明:随着降雨量的增大,参与泥石流活动的松散物质方量持续增加,但当24 h降雨量超过200 mm后,泥石流沟的危险度等级不再发生变化;17条泥石流沟中4条为中危险度,12条为高危险度,1条为极高危险度。这说明研究区地质灾害问题相当严峻,在多雨季节存在泥石流群发的可能性,直接威胁到居住在泥石流沟附近的人民群众生命财产安全;因此,对于有直接危害对象的高危险度及其以上的泥石流沟,应该按照高等级设防标准进行工程治理及发布预警报。同时也说明,将滑坡、泥石流作为灾害链研究具必要性和可行性。 相似文献
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本文是一篇关于全国崩塌滑坡泥石流分布图编制方法探索的论文。基于全国崩塌滑坡泥石流数据库,根据图面承载能力,用不同灾害类型之间数量比例和网格密度共同控制的方法,筛选出代表整体发育分布规律的崩塌滑坡泥石流隐患点;用点状符号表达崩塌滑坡泥石流隐患点空间分布特征,线状符号表达崩塌滑坡泥石流时间分布特征,面状普染色表达崩塌滑坡泥石流发育数量分级特征;结合人们正常视觉感受,建立均衡的构图,选用协调美观的色彩,合理处置图上点、线、面各图层之间的冲突以及图层内部分级关系,编制集科学与艺术为一体的全国崩塌滑坡泥石流分布图。 相似文献
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云南省德钦县曾多次暴发较大规模的泥石流,是云南遭受地质灾害最严重的地区之一。根据直溪河泥石流的分区、物源、流体和堆积等特征,首先确定了直溪河泥石流的5种成灾模式:崩塌-碎屑流、岩质滑坡-碎屑流、土石混合体滑坡-碎屑流、松散堆积层-基岩接触面滑坡-碎屑流和松散堆积层内滑坡-碎屑流;其次,采用FLO-2D模型对直溪河在10年、20年、50年和100年一遇暴雨周期下发生泥石流时的运动情况进行模拟,定量分析了不同降雨重现期的最大流速、最大堆积深度、冲出沟口堆积距离和体积规模。结果表明:该泥石流暴发时具有启动加速度大、流速快、破坏力强、流通区长的特点;当100年一遇的泥石流发生时,其最大流速达到了3.07 m/s;最大泥深为2.27 m;泥石流冲出方量为84419 m3;致灾面积达到91600 m2。研究结果可为直溪河泥石流灾害防治与治理提供数据参考,为德钦县防灾减灾工程设计提供依据。 相似文献
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《Engineering Geology》2004,73(3-4):193
In two events, on November 15 and 17, 2000, near the Mangart Mountain (2679 m a.s.l.), NW Slovenia, two translational landslides (debris flow slides) with a total volume of more than 1.5 million m3 occurred on the Sto
e slope composed of morainic material filled with silt fraction. The first landslide was associated with a dry and the second landslide with a wet debris-flow, respectively. The rain gauging station in the village of Log pod Mangartom recorded 1638.4 mm of rainfall (more than 60% of the average annual precipitation) in the 48 days before the events (rainfall intensity of 1.42 mm/h in 1152 h). The recorded rainfall depth has a recurrence interval of more than 100 years. Other recorded rainfall depths of shorter duration (481.6 mm in 7 days, 174.0 mm in 24 h, 70 mm in 1 h) have recurrence intervals of much less than 100 years. A hydrological analysis of the event showed that the increase in runoff coefficients during the wet period in autumn 2000 before the landslide was as high as two- to threefold. An analysis using natural isotopes of δ18O and tritium of water samples from the Sto
e landslide area has shown permanent but slow exfiltration of underground waters from a reservoir in the slope. In the case of low-intensity and long-duration rainfall in autumn 2000, relatively low permeable (10−7 m/s) morainic material was nearly saturated but remained stable (average porosity 21%, water content 20%, liquid limit 25%) until high artesian pressures up to 100 m developed in the slope by slow exfiltration from the relatively high permeable (10−5 m/s) massive dolomite. The Sto
e landslide (two debris flow slides) was triggered by high artesian pressures built in the slope after long-duration rainfall. The devastating debris-flows formed from the landslide masses by infiltration of rainfall and surface runoff into the landslide masses and by their liquefaction. 相似文献
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四川都江堰三溪村710高位山体滑坡研究 总被引：2，自引：0，他引：2
2013年7月10日上午10时,四川都江堰市中兴镇三溪村受极端暴雨影响发生高位山体滑坡灾害,滑坡-碎屑堆积体方量超过150104m3,其中1#滑坡-碎屑堆积体长度1.26km,造成三溪村一组重大人员伤亡。笔者在野外实地调查和室内研究分析的基础上,总结了都江堰三溪村滑坡的基本特征,研究了其启动运动机制和滑动速度,主要认识如下:（1）该滑坡为一处高位山体滑坡,后缘白垩系砂砾岩地层高速滑动后剧烈撞击-铲刮-偏转后铲动坡体上的松散堆积层而形成高位山体滑坡-碎屑流灾害。（2）根据滑坡的运动及堆积特征,将1#滑坡划分为砂砾岩滑动区、碰撞铲刮区和碎屑流堆积覆盖区3部分。（3）7月8日8时至10日8时,中兴镇三溪村的持续强降雨天气过程（都江堰市3d的降雨量相当于该地区年降雨总量的44.1%）,直接触发了滑坡的发生。（4）三溪村滑坡的发生受2008年汶川地震、特殊的岩土体性质、地形地貌条件以及极端暴雨事件的综合影响,地震、地形为其发育提供了基础条件,极端暴雨事件为其直接诱发因素。（5）建议加强高位山体滑坡的研究,尤其是远程滑坡-碎屑流的早期识别和预警。 相似文献
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A geotechnical investigation of the retrogressive Yaka Landslide and the debris flow threatening the town of Yaka (Isparta,SW Turkey) 总被引：2，自引：1，他引：1
In this study the factors affecting the retrogressive Yaka Landslide, its mechanism and the hazard of debris flow on the town of Yaka are investigated. In the landslide area, the first landslide was small and occurred in March 2006 on the lower part of the Alaard?ç Slope near the Gelendost District town of Yaka (Isparta, SW Turkey). The second, the Yaka Landslide, was large and occurred on 19 February 2007 in the soil-like marl on the central part of Alaard?ç Slope. The geometry of the failure surface was circular and the depth of the failure surface was about 3 m. Following the landslide, a 85,800 m3 of displaced material transformed to a debris flow. Then, the debris flow moved down the Eglence Valley, traveling a total distance of about 750 m. The town of Yaka is located 1,600 m downstream of Eglence Creek and hence poses a considerable risk of debris flow, should the creek be temporarily dammed as a result of further mass movement. Material from the debris accumulation has been deposited on the base of Eglence Valley and has formed a debris-dam lake behind a debris dam. Trees, agricultural areas, and weirs in the Eglence Creek have seen serious damage resulting from the debris flow. The slope angle, slope aspect and elevation of the area in this study were generated using a GIS-based digital elevation model (DEM). The stability of the Alaard?ç Slope was assessed using limit equilibrium analysis with undrained peak and residual shear strength parameters. In the stability analyses, laboratory test results performed on the soil-like marls were used. It was determined that the Alaard?ç Slope is found to be stable under dry conditions and unstable under completely saturated conditions. The Alaard?ç Slope and its vicinity is a paleolandslide area, and there the factor of safety for sliding was found to be about 1.0 under saturated conditions. The Alaard?ç Slope and the deposited earthen materials in Eglence Creek could easily be triggered into movement by any factors or combination of factors, such as prolonged or heavy rainfall, snowmelt or an earthquake. It was established that the depth of the debris flow initiated on the Yaka Landslide reached up to 8 m in Eglence Creek at the point it is 20 m wide. If this deposited material in Eglence Creek is set into motion, the canal that passes through Yaka, with its respective width and depth of 7 and 1.45 m, could not possibly discharge the flow. The destruction or spillover of this canal in Yaka could bring catastrophic loss to residents which are located within 3–5 m of the bank of the canal. Furthermore, if material present in the landslide source area slides and this displaced material puts pressure on the unstable deposited material in Eglence Creek, even more catastrophic loss would occur to the town of Yaka. In this study, it was determined that debris flows are still a major hazard to Yaka and its population of 3,000. The results provided in this study could help citizens, planners, and engineers to reduce losses caused by existing and future landslides and debris flow in rainfall and snowmelt conditions by means of prevention and mitigation. 相似文献
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2010年“8.8”舟曲特大山洪泥石流灾害形成的气候特征及地质地理环境分析 总被引：2，自引：2，他引：0
利用舟曲气象和地质资料,分析了2010年8月8日发生的"8.8"舟曲特大山洪泥石流灾害形成的气候特征和地质地理环境.这次泥石流是在舟曲特殊的地质地貌和地理环境下,由于前期干旱,突遇强降水而发生的一次特大地质灾害.崩塌、滑坡、地震和人为因素,特别是"5.12"汶川地震,较大程度上破坏了舟曲地质,为泥石流提供了丰富的物质来源;前期干旱在一定程度上加剧了这次灾害;超历史极值的强降水是触发泥石流的直接因素.通过对舟曲气候研究表明,7、8月降雨频繁,而且过程雨量大,尤其8月上旬大雨发生频率最高,应密切关注可能引发的地质灾害.加强对地质地貌的保护,研究历史气候及月季气候特征对泥石流发生的影响,确定在不同地形和地质地貌背景下的泥石流降水量阈值,对泥石流灾害发生的预报有着十分重要的意义. 相似文献
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2020年6月17日丹巴县梅龙沟爆发了一次大规模泥石流,一次性冲出固体物质42.7×104 m3,形成泥石流-堰塞坝-溃决洪水-滑坡灾害链,造成5100余户2.12万余人被迫转移,直接经济损失达8亿元。根据现场调查、无人机航拍以及遥感解译,分析梅龙沟泥石流的成因及致灾机理,阐述了“物源成因”、“降雨激发”和“地形促进”对泥石流形成产生的影响。结果表明:（1）梅龙沟泥石流是在前期累计降雨和短时强降雨共同作用下形成;（2）梅龙沟泥石流源头为大石堡沟,起动模式为“沟岸垮塌-泥石流”;（3）泥石流沟内持续的物源补给以及东风棚子、梅龙村、大邑村三处大型滑坡产生的级联堵溃效应,致使泥石流流量不断放大,最终导致大量固体物质冲出沟口;（4）沟口形成的堰塞坝-溃决洪水-阿娘寨滑坡灾害链进一步增强了泥石流的致灾能力;（5）现阶段梅龙沟内物源丰富,临界启动降雨阈值降低,极易在雨季发生大规模泥石流,建议及时采取综合防治措施。 相似文献
16.
Guruh Samodra Danang Sri Hadmoko Ghalih Nur Wicaksono Indriya Parahita Adi Maulana Yudinugroho Sandy Budi Wibowo Hatma Suryatmojo Taufik Hery Purwanto Barandi Sapta Widartono Franck Lavigne 《Landslides》2018,15(5):985-993
The Clapar landslide induced debris flow consisted of the Clapar landslide occurred on 24 March 2017 and the Clapar debris flow occurred on 29 March 2017. The first investigation of the Clapar landslide induced debris flow was carried out two months after the disaster. It was followed by UAV mapping, extensive interviews, newspaper compilation, visual observation and field measurements, and video analysis in order to understand chronology and triggering mechanism of the landslide induced debris flow in Clapar. The 24 March 2016 landslide occurred after 5 hours of consecutive rainfall (11,2 mm) and was affected by combination of fishponds leak and infiltration of antecedent rain. After five days of the Clapar landslide, landslide partially mobilized to form debris flow where the head scarp of debris flow was located at the foot of the 24 March 2016 landslide. The Clapar debris flow occurred when there was no rainfall. It was not generated by rainstorm or the surface erosion of the river bed, but rather by water infiltration through the crack formed on the toe of the 24 March 2016 landslide. Supply of water to the marine clay deposit might have increased pore water pressure and mobilized the soil layer above. The amount of water accumulated in the temporary pond at the main body of the 24 March 2016 landslide might have also triggered the Clapar debris flow. The area of Clapar landslide still shows the possibility of further retrogression of the landslide body which may induce another debris flow. Understanding precursory factors triggering landslides and debris flows in Banjarnegara based on data from monitoring systems and laboratory experiments is essential to minimize the risk of future landslide. 相似文献
17.
寺儿沟流域位于甘肃省兰州市西固区,历史上曾发生过大规模泥石流,造成重大人员伤亡和财产损失。文章基于野外调查和遥感解译,结合已有文献成果和室内测试,研究寺儿沟泥石流物源特征及影响因素,采用FLO-2D软件模拟分析泥石流的危险性。研究结果表明：寺儿沟以黏性泥石流为主,表现为低频活动,目前处于衰退期;寺儿沟流域内物源丰富,可分为坡面型物源、崩滑型物源、沟道型物源和人为型物源共4种,其中崩滑型、沟道型物源控制了泥石流的暴发规模;而一次性冲出量的大小主要取决于泥石流起动时崩滑体的发育程度,崩滑体越发育,一次性冲出量越大,泥石流规模越大;在临界降雨条件下,寺儿沟将会暴发泥石流,中—高危险区集中于流通区,严重威胁冲沟内构筑物如兰西高铁、环城高速等安全运营。当遭遇极端强降雨时,寺儿沟将暴发更大规模泥石流。因此,有必要进一步研究极端天气条件下泥石流的危险性,为区内泥石流的防灾减灾提供地质依据。 相似文献
18.
Every year, and in many countries worldwide, wildfires cause significant damage and economic losses due to both the direct
effects of the fires and the subsequent accelerated runoff, erosion, and debris flow. Wildfires can have profound effects
on the hydrologic response of watersheds by changing the infiltration characteristics and erodibility of the soil, which leads
to decreased rainfall infiltration, significantly increased overland flow and runoff in channels, and movement of soil. Debris-flow
activity is among the most destructive consequences of these changes, often causing extensive damage to human infrastructure.
Data from the Mediterranean area and Western United States of America help identify the primary processes that result in debris
flows in recently burned areas. Two primary processes for the initiation of fire-related debris flows have been so far identified:
(1) runoff-dominated erosion by surface overland flow; and (2) infiltration-triggered failure and mobilization of a discrete
landslide mass. The first process is frequently documented immediately post-fire and leads to the generation of debris flows
through progressive bulking of storm runoff with sediment eroded from the hillslopes and channels. As sediment is incorporated
into water, runoff can convert to debris flow. The conversion to debris flow may be observed at a position within a drainage
network that appears to be controlled by threshold values of upslope contributing area and its gradient. At these locations,
sufficient eroded material has been incorporated, relative to the volume of contributing surface runoff, to generate debris
flows. Debris flows have also been generated from burned basins in response to increased runoff by water cascading over a
steep, bedrock cliff, and incorporating material from readily erodible colluvium or channel bed. Post-fire debris flows have
also been generated by infiltration-triggered landslide failures which then mobilize into debris flows. However, only 12%
of documented cases exhibited this process. When they do occur, the landslide failures range in thickness from a few tens
of centimeters to more than 6 m, and generally involve the soil and colluvium-mantled hillslopes. Surficial landslide failures
in burned areas most frequently occur in response to prolonged periods of storm rainfall, or prolonged rainfall in combination
with rapid snowmelt or rain-on-snow events. 相似文献
19.
贵州关岭大寨高速远程滑坡碎屑流研究 总被引：15，自引：1，他引：14
2010年6月28日,贵州关岭因突降暴雨发生高速远程滑坡,滑程约1.5km,体积约174.9万m3,两个村组被毁,99人遇难。滑坡区位于西南地区常见的煤系地层区,上部为灰岩、白云岩,中部为相对较缓的砂岩地层,下部为页岩、泥岩地层,局部含煤,具有上硬下软的山体地质结构和上部富水下部隔水的水文地质结构,极易形成滑坡地质灾害。从地形上看,斜坡上陡下缓,形似靴状地形,上部陡峭地形导致山体易于失稳,而中下部开阔伸展良好的沟谷提供了远程的运动条件,较大的势能向动能的转化,容易形成高速远程滑坡碎屑流。6月27日和28日的降雨是触发此起特大灾害的主要原因,其24h降雨量达310mm,超过了当地近60a来的气象记录,分析表明,降雨产生的沟谷径流量是平时强降雨(100～150mmd-1)的沟谷径流的2倍之上,一是在滑源区砂岩裂隙岩体中形成静水压力和渗透压力,触使滑坡的失稳下滑; 二是在沟谷中产生地表径流,为碎屑流远程流动形成饱水下垫面,导致了碎屑流流动距离和速度的显著增加。近年来随着极端强降雨等灾害性天气的重现期缩短,高速远程滑坡造成的群死群伤特大地质灾害在我国呈逐渐增加趋势,应加强对这种灾害类型的调查与防范,特别是要进行滑坡安全避让范围和逃逸速度的研究。 相似文献