芦山地震后雅安市雨城区地质灾害危险性评价

本文通过调查和收集"4·20"芦山地震后雅安市雨城区区域地形、地质、水文条件及地质灾害发生情况等资料,分析雨城区地质灾害的分布规律、发育特征和灾害特点,选用层次分析法的理论进行权重确定,采用地质构造、地震烈度、地形坡度、高程、河流、降雨6个评价因子对研究区地质灾害危险性进行评价。将危险性划分为高、中和低三个等级。     

模糊方法在地质灾害危险性评价中的应用

地质灾害评估是协调人地关系研究的重要内容,可为大型工程建设的前期工作提供基本依据。本文采用模糊综合评价法,选择历史灾害危险性、潜在灾害危险性2个基本要素和相应的8个评价因子,对甘肃省洮河莲麓水电站建设用地地质灾害危险性进行了评估。结果表明:河谷地貌区和山间盆地地貌区地质灾害危险性中等,中山地貌区地质灾害危险性小。     

中国地震次生地质灾害危险性评价

地震次生地质灾害主要指地震引起的崩塌、滑坡、塌陷、地裂缝、砂土液化。震级大于5级、烈度超过Ⅵ度的地震可能引发不同程度的地质灾害,震级和烈度越高,次生地质灾害越严重。本文根据中国历史地震次生地质灾害活动程度及发生条件,以地(市、区、盟)为单元,进行了危险性评价:高度和中度危险区主要分布在中国中部的陕甘宁川渝滇藏地区,形成一个大致NE向高危险带,其余大部分地区为轻度危险区。      

基于层次分析法的登封市地质灾害危险性评价

文章针对登封市地质环境条件、发育特征等特性,选取了灾害点密度、岩土体类型、断裂发育程度、地貌类型、坡度、降雨量、人类工程活动等7个地质灾害危险性评价因子,通过层次分析法确定评价因子权重,并采用专家系统法赋值,建立了该市地质灾害危险性评价模型。通过划分评价单元及利用危险性评价模型,基于Arcgis空间分析功能将该市地质灾害危险性分为低危险区、中危险区和高危险区。研究成果对相似地区地质灾害危险性的划分也提供了一定的借鉴意义。     

矿山地质灾害危险性评价

矿山地质灾害危险性评价的影响因素较多,又多具不确定性和模糊性。目前对矿山地质灾害危险性评价主要采用定性的专家打分法,具有一定的主观性。基于以上考虑,在分析矿山地质灾害形成影响因素的基础上,应用模糊层次分析法(FAHP)量化了各评价因素的权重,并将该权重引入模糊综合评价,建立了基于FAHP的模糊综合评价的矿山地质灾害危险性评价数学模型。并应用此方法对陕北某矿区的地质灾害危险性进行了评价,评价结果与实际调查结果比较吻合。     

基于人工神经网络的区域地质灾害危险性预测评价

地质灾害危险性预测评价的准确性,主要取决于基础资料的可靠性和数学模型的合理性。论文结合工程实例,尝试用人工神经网络方法(改进的神经网络BP模型)对区域地质灾害危险性预测进行评价研究。然后与目前常用的方法(如层次分析法、信息量法和模糊综合评判法等)所得出的结果相比较。结果表明,运用人工神经网络方法对区域地质灾害危险性预测评价相对常用方法更准确、可靠,具有一定的实用意义及推广价值。     

基于模糊数学的地质灾害危险性评价

陕西省引汉济渭工程跨越秦岭构造剥蚀山地和断陷盆地,地质环境条件差,发育地质灾害点72处。选取地质环境条件、地质灾害发育现状和地质灾害预测为评价指标,分别赋予隶属度值;将工程剖分为284个评价单元,采用模糊数学综合评判法计算每个单元的隶属度值,确定危险性小的单元255个,危险性中等的单元29个;说明工程主要位于危险性小的区段。     

地震恢复重建规划区地质灾害特征及危险性评价

通过收集有关资料和实地勘察,描述并总结了四川省青川县板桥乡城建设用地地质灾害的发育特征。根据地质灾害点目前的稳定状态和潜在危害程度,定性评价了区内各地质灾害点的危险性。并基于各地质灾害点的危险程度,综合区内的地形地貌、地质条件和人为因素、气象水文条件,对青）ll县板桥乡地质灾害危险性进行了分区,为建设用地的规划设计提供了依据：     

陕西陇县地质灾害危险性分区评价

在陇县地质灾害详细调查的基础上,通过统计分析确定了各类主要影响因素,采用信息量法和定性评价方法分别进行了地质灾害的危险性评价。建立了地质灾害评价指标体系,确定了地质灾害危险性判别标准,进行了地质灾害危险区划。共划分为高危险区、中危险区、低危险区和极低危险区4个等级,在此基础上,又划分了12个亚区。其中高危险区面积为619.19km2,占总面积的25.79%,中危险区面积为509.74km2,占总面积的21.23%,低危险区面积为711.75km2,占总面积的29.65%,极低危险区面积为559.87km2,占全区面积的23.32%。     

基于GIS的四川广安区地质灾害危险性评价

近年广安区洪水灾害频发诱发大量地质灾害,严重威胁人民的生命财产安全。文章结合广安区地质灾害调查与区划项目,在地质灾害野外实际调查的基础上,选取坡度、坡向、地层岩性、地质构造、水系、降雨作为影响地质灾害发生的评价因子。运用层次分析法确定各评价因子的权重并建立地质灾害危险性指数模型,通过GIS系统的空间分析功能进行栅格运算,完成广安区地质灾害危险性区划。评价结果与实际调查情况基本相吻合,可为今后广安区地质灾害的预测及预防提供了科学参考。     

雅安雨城区重点场镇地质灾害综合防治模式

以雅安市雨城区多营重点场镇为例,系统调查多营镇地质灾害分布特征,并对城镇进行地质灾害危险性评估,适宜性分区。基于上述特征,提出了多营镇地质灾害综合治理方案,并对已完成项目效果进行分析。     

Geohazards Induced by the Lushan Ms7.0 Earthquake in Sichuan Province, Southwest China:Typical Examples, Types and Distributional Characteristics

Geohazards induced by the Lushan Ms 7.0 earthquake on April 20, 2013 mainly have four types: collapse, landslide, slope debris flow, and sand-soil liquefaction. These geohazards mainly occurred near the epicenter, on steep slopes or below cliffs in high mountain and deep valley areas, and at or near fault ends. They have no obvious relationships to active faults, but their relationships to the weathering degree and structures of rock and rock mass are obvious. Compared with the Wenchuan Ms 8.0 earthquake on May 12, 2008, the Lushan earthquake is relatively little in the impact force and the throwing amount. All of these should be related to the magnitude of this earthquake, not very large but not very little. This character of the Lushan earthquake would make some processes uncompleted so as to bring about some concealed geohazards. Finally, in order to deal with challenges presented by such conceal geohazards, some brief recommendations are put forward.     

广西资源县石材加工厂建设项目地质灾害危险性评估

本文对广西资源县骊马矿业有限公司石材加工厂项目建设过程中,可能引发的崩塌、滑坡、泥石流等地质灾害隐患危险性进行了系统的评估和和预测,并针对不同类别的地质灾害隐患,提出了混凝平流沉淀、卧螺离心沉降、泥浆定期抽吸外运填埋、修建挡土墙、修建截水沟和种植速生植被等科学有效的防治措施,对项目建设活动安全有序、高效地开展,具有很好的指导意义,并可作为其他同类项目地质灾害评估的类比参照。     

拉萨市郊地质灾害预测及防治辅助决策

拉萨市郊区的自然环境和地质环境较为脆弱,在雨量充沛的6⁹月易形成崩塌、滑坡和泥石流等地质灾害。为了对地质灾害进行有效的预测和防治辅助决策,根据野外调查资料,结合模糊数学、小波人工神经网络和灰色决策等理论进行降雨量预测、危险性计算以及防治辅助决策,并运用Java SE Development Kit 8平台开发了地质灾害预测及防治辅助决策系统。     

四川雅安市雨城区降雨诱发滑坡研究

降雨是滑坡灾害的重要诱发因素之一。通过详细的地质灾害调查及地质灾害与降雨相关关系的研究,得出降雨对雅安雨城区地质灾害诱发作用的规律并进一步定量评价了诱发因素级别。研究发现,降雨量对滑坡的诱发因素可划分为4级,1d降雨量分级临界值分别为20mm、50mm和100mm,3d降雨量分级临界值分别为100mm、150mm和240mm。这一研究成果为雅安雨城区地质灾害预警预报提供了基础。     

Short-term economic effect of the M7.0 Lushan Earthquake

To estimate the short-term economic effect of the 2013 M7.0 Lushan Earthquake, the constant mean return model and the market model of event study are adopted. On the levels of the whole stock market, some typical sectors, regional stocks, and the stock in the affected area, effects are measured. Three indices are adopted to measure the whole market. Nine indices are selected to observe the abnormal returns of the sectors, involving Energy, Materials, Industries, Consumer, Health care, Finance, Information technology, Telecommunication service, and Utilities. In Sichuan Province, there are 82 registered stocks with enough trading data, whose abnormal returns are calculated to test the short-term effect on the regional economy. And in the affected area, only one stock is registered. The result indicates that abnormal returns from the whole market, nine sectors, and the region are not significant at the level of 0.01 in the following 10 days.     

地震次生地质灾害风险评估集对态势分析

5．12四川汶川8级强震引发了大量次生地质灾害,加剧了灾情并严重影响抗震救灾。地震次生地质灾害受多重因素制约,其孕育与致灾过程具有不确定性。利用集对分析原理与方法,对地震次生地质灾害进行同异反态势分析,拟定了风险评估的集对分析同一度、差异度、对立度等指标体系的构建原则与赋值标准,对承灾体系统的不确定性及其作用作了刻画与分析,建立了不同风险分区代表性的集对分析联系度表达式,为地震灾害研究提供了可资借鉴的新思路和技术方法。     

Seismogenic Structure of the April 20, 2013, Lushan Ms7 Earthquake in Sichuan

At 08:02 on April 20, 2013, a Ms7.0 earthquake occurred in Lushan, Ya'an, in the Longmenshan fault zone, Sichuan. The epicenter was located between Taiping Town and Shuangshi Town, Lushan County and the maximum earthquake intensity at the epicenter reached class IX. Field investigations in the epicenter area found that, although buildings were seriously damaged, no obvious surface rupture structure was produced, only some ground fissures and sand blows and water ejection phenomena being seen. An integrated analysis of high-resolution remote sensing image interpretation, mainshock and aftershock distribution, and focal mechanism solutions indicated that this earthquake was an independent rupturing event in the southwestern segment of the Longmenshan fault zone, belonging to the thrust-type earthquake. Ruptures occurred along the south-central segment of the Shuangshi-Dachuan fault and the principal rupture plane dipped SW at 33-43°. It is inferred that the Lushan earthquake might be related to the ramp activity of the basal detachment zone (13-19 km) of the Longmenshan fault zone. Historically, there occurred at least two Ms6-6.5 earthquakes along the Shuangshi-Dachuan fault zone; thus it is thought that the Lushan earthquake, different from the Wenchuan earthquake, was a characteristic one in the southwestern segment of the Longmenshan fault zone. In-situ stress measurements indicated the Lushan earthquake was the result of stress release of the southwestern segment of the Longmenshan fault zone after the Wenchuan earthquake. This paper analyzes the tectonic setting of the seismogenic structure of this earthquake.     

四川雅安市雨城区降雨诱发滑坡临界值初步研究

四川省雅安市雨城区位于四川盆地西部,素有"雨城"之称。地质灾害以滑坡为主,且有群发性、浅层、规模小、降雨诱发的特点。作者分析了雨城区大量历史滑坡和降雨量数据,结合雨城区滑坡发育特点,选择3日(72h)内发生2个以上滑坡的点作为统计分析样本,进行不同阶段降雨量耦合关系分析,应用滑坡前3日累计降雨量与3日前15日累计降雨量,建立了滑坡发生与降雨量的统计关系:在雨城区,当前期无降雨、3日累计降雨量达到70mm时,将有滑坡发生;15日累计降雨量达到339mm时,也将可能出现滑坡。