In this paper, we propose the principle, methods and calculating formulas for determining the certainty factors of earthquake precursory anomaly evidences CF (E). Based on the guidebooks for earthquake prediction, we ...In this paper, we propose the principle, methods and calculating formulas for determining the certainty factors of earthquake precursory anomaly evidences CF (E). Based on the guidebooks for earthquake prediction, we give the methods of determining the CF values of 22 evidences (including seismic gap, belt, b-value, c-value, velocity ratio, strengthen of anomalous activities, quiet of anomalous activities, seismic window, earthquake swarm,earthquake sequence, coda wave, initial motion of P wave, stress drop, geoelectricity, geomagnetism, stress,ground tilt, ground water level, radon and hydrochemistry, gravity, space environment and macroscopic anomalies), and show three examples. The purposes are to use the Expert System for Earthquake Prediction (ESEP) further.展开更多
A new approach combining the certainty factor(CF) and analytic hierarchy process(AHP) methods was proposed to assess landslide susceptibility in the Ziyang district, which is situated in the Qin-Ba Mountain region, Ch...A new approach combining the certainty factor(CF) and analytic hierarchy process(AHP) methods was proposed to assess landslide susceptibility in the Ziyang district, which is situated in the Qin-Ba Mountain region, China. Landslide inventory data were collected based on field investigations and remote sensing interpretations. A total of 791 landslides were identified. A total of 633 landslides were randomly selected from this data setas the training set, and the remaining landslides were used for validation as the test set. Nine factors, including the slope angle, slope aspect, slope curvature, lithology, distance to faults, distance to streams, precipitation, road network intensity degree and land use were chosen as the landslide causal factors for further susceptibility assessment. The weight of each factor and its subclass were calculated by AHP and CF methods. Landslide susceptibility was compared between the bivariate statistical method and the proposed CF-AHP method. The results indicate that the distance to streams, distance to faults and lithology are the most dominant causal factors associated with landslides. The susceptibility zonation was categorized into five classes of landslide susceptibility, i.e., very high, high, moderate, low and very low level. Lastly, the relative operating characteristics(ROC) curve was used to validate the accuracy of the new approach, and the result showed a satisfactory prediction rate of 78.3%, compared to 69.2% obtained with the landslide susceptibility index method. The results indicate that the CF-AHP combined method is more appropriate for assessing the landslide susceptibility in this area.展开更多
In the meizoseismal areas hit by the China Wenchuan earthquake on May 12, 2008, the disasterprone environment has changed dramatically, making the susceptibility assessment of debris flow more complex and uncertain. A...In the meizoseismal areas hit by the China Wenchuan earthquake on May 12, 2008, the disasterprone environment has changed dramatically, making the susceptibility assessment of debris flow more complex and uncertain. After the earthquake, debris flow hazards occurred frequently and effective susceptibility assessment of debris flow has become extremely important. Shenxi gully in Du Jiangyan city, located in the meizoseismal areas, was selected as the study area. Based on the research of disaster-prone environment and the main factors controlling debris flow, the susceptibility zonations of debris flow were mapped using factor weight method(FW), certainty coefficient method(CF) and geomorphic information entropy method(GI). Through comparative analysis, the study showed that these three methods underestimated susceptible degree of debris flow when used in the meizoseismal areas of Wenchuan earthquake. In order to solve this problem, this paper developed a modified certainty coefficient method(M-CF) to reflect the impact of rich loose materials on the susceptible degree of debris flow. In the modified method, the distribution and area of loose materials were obtained by field investigations and postearthquake remote sensing image, and four data sets, namely, lithology, elevation, slop and aspect, wereused to calculate the CF values. The result of M-CF method is in agreement with field investigations and the accuracy of the method is satisfied. The method has a wide application to the susceptibility assessment of debris flow in the earthquake stricken areas.展开更多
文章以德格县为研究区,以7 m DEM进行地形分析处理,并结合相关调查数据建立了德格县滑坡灾害数据库,通过选取的地震峰值加速度、断裂带、水系、坡度、坡向、高程、岩性等7个指标,在GIS技术支持下,利用信息量模型(I)、层次分析法模型(AHP...文章以德格县为研究区,以7 m DEM进行地形分析处理,并结合相关调查数据建立了德格县滑坡灾害数据库,通过选取的地震峰值加速度、断裂带、水系、坡度、坡向、高程、岩性等7个指标,在GIS技术支持下,利用信息量模型(I)、层次分析法模型(AHP)、确定性系数模型(CF)相互耦合对研究区灾害敏感性评价,再分析得到活动频率因素对研究区全县域进行危险性评价,将得到的结果分成4个区域,分别为高危险区、较高危险区、中危险区、低危险区,其中高、较高危险区占总面积2.23%。其中,滑坡灾害占总灾害的42%。评价结果与实际调查结果符合程度较高,能够为该地域未进行实地调查的地方进行相关滑坡灾害的预测预报,并对安全防治提供技术支持,亦可以为其他地区滑坡灾害危险性评价提供理论指导和技术参考。展开更多
攀枝花市矿产资源丰富,采矿历史悠久,开采活动强度大,地质结构复杂,生态环境脆弱,矿山地质灾害频发.基于2019年的三江(怒江,澜沧江,金沙江)北段矿产开发环境遥感监测调查资料,在分析矿山地质灾害发育规律与影响因素关系的基础上,选取坡...攀枝花市矿产资源丰富,采矿历史悠久,开采活动强度大,地质结构复杂,生态环境脆弱,矿山地质灾害频发.基于2019年的三江(怒江,澜沧江,金沙江)北段矿产开发环境遥感监测调查资料,在分析矿山地质灾害发育规律与影响因素关系的基础上,选取坡度、工程地质岩组、距断层的距离、降水量、植被覆盖度、距河流的距离以及距开采活动面的距离7个评价因子,借助ArcGIS软件平台,采用确定性系数(Certainty Factor,CF)模型、信息量模型以及CF与信息量耦合模型开展攀枝花市矿山地质灾害易发性评价研究.结果表明,工程地质岩组、植被覆盖度、距开采活动面的距离是影响矿山地质灾害分布的控制因子;经过ROC(Receiver Operating Characteristic Curve,ROC)曲线检验,CF与信息量耦合模型的AUC(Area Under the Curve,AUC)值高达0.909,表明耦合模型比单一模型的评价精度高,其精度为耦合模型>信息量模型>确定性系数模型;耦合模型的易发性分区为极高易发区(5.24%)、高易发区(11.67%)、中易发区(41.66%)和低易发区(41.43%),其中极高和高易发区主要分布在开采活动强度较大的煤矿、铁矿和花岗岩矿矿山,即主要分布在仁和区、东区、盐边县和米易县.展开更多
文摘In this paper, we propose the principle, methods and calculating formulas for determining the certainty factors of earthquake precursory anomaly evidences CF (E). Based on the guidebooks for earthquake prediction, we give the methods of determining the CF values of 22 evidences (including seismic gap, belt, b-value, c-value, velocity ratio, strengthen of anomalous activities, quiet of anomalous activities, seismic window, earthquake swarm,earthquake sequence, coda wave, initial motion of P wave, stress drop, geoelectricity, geomagnetism, stress,ground tilt, ground water level, radon and hydrochemistry, gravity, space environment and macroscopic anomalies), and show three examples. The purposes are to use the Expert System for Earthquake Prediction (ESEP) further.
基金financial support from National Natural Science Foundation of China (Grant No. 41272282)National Natural Science Foundation of China-Youth Foundation (Grant No. 41402254)+1 种基金geological disaster survey projects of China Geological Survey (Grant No. 1212011220135, Grant No. DDW2016-01)the Fundamental Research Funds for the Central Universities (Grant No. 310826175030)
文摘A new approach combining the certainty factor(CF) and analytic hierarchy process(AHP) methods was proposed to assess landslide susceptibility in the Ziyang district, which is situated in the Qin-Ba Mountain region, China. Landslide inventory data were collected based on field investigations and remote sensing interpretations. A total of 791 landslides were identified. A total of 633 landslides were randomly selected from this data setas the training set, and the remaining landslides were used for validation as the test set. Nine factors, including the slope angle, slope aspect, slope curvature, lithology, distance to faults, distance to streams, precipitation, road network intensity degree and land use were chosen as the landslide causal factors for further susceptibility assessment. The weight of each factor and its subclass were calculated by AHP and CF methods. Landslide susceptibility was compared between the bivariate statistical method and the proposed CF-AHP method. The results indicate that the distance to streams, distance to faults and lithology are the most dominant causal factors associated with landslides. The susceptibility zonation was categorized into five classes of landslide susceptibility, i.e., very high, high, moderate, low and very low level. Lastly, the relative operating characteristics(ROC) curve was used to validate the accuracy of the new approach, and the result showed a satisfactory prediction rate of 78.3%, compared to 69.2% obtained with the landslide susceptibility index method. The results indicate that the CF-AHP combined method is more appropriate for assessing the landslide susceptibility in this area.
基金Financial support was provided by Ministry of Water Resources welfare industry funding(Grant No.201301058)Key Laboratory of Mountain Hazards and Earth Surface Processes independent project funding:Dynamic process and buried risk of debris flow in Shenxi gully after Wenchuan earthquakethe international cooperation project of Ministry of Science and Technology(Grant No.2013DFA21720)
文摘In the meizoseismal areas hit by the China Wenchuan earthquake on May 12, 2008, the disasterprone environment has changed dramatically, making the susceptibility assessment of debris flow more complex and uncertain. After the earthquake, debris flow hazards occurred frequently and effective susceptibility assessment of debris flow has become extremely important. Shenxi gully in Du Jiangyan city, located in the meizoseismal areas, was selected as the study area. Based on the research of disaster-prone environment and the main factors controlling debris flow, the susceptibility zonations of debris flow were mapped using factor weight method(FW), certainty coefficient method(CF) and geomorphic information entropy method(GI). Through comparative analysis, the study showed that these three methods underestimated susceptible degree of debris flow when used in the meizoseismal areas of Wenchuan earthquake. In order to solve this problem, this paper developed a modified certainty coefficient method(M-CF) to reflect the impact of rich loose materials on the susceptible degree of debris flow. In the modified method, the distribution and area of loose materials were obtained by field investigations and postearthquake remote sensing image, and four data sets, namely, lithology, elevation, slop and aspect, wereused to calculate the CF values. The result of M-CF method is in agreement with field investigations and the accuracy of the method is satisfied. The method has a wide application to the susceptibility assessment of debris flow in the earthquake stricken areas.
文摘文章以德格县为研究区,以7 m DEM进行地形分析处理,并结合相关调查数据建立了德格县滑坡灾害数据库,通过选取的地震峰值加速度、断裂带、水系、坡度、坡向、高程、岩性等7个指标,在GIS技术支持下,利用信息量模型(I)、层次分析法模型(AHP)、确定性系数模型(CF)相互耦合对研究区灾害敏感性评价,再分析得到活动频率因素对研究区全县域进行危险性评价,将得到的结果分成4个区域,分别为高危险区、较高危险区、中危险区、低危险区,其中高、较高危险区占总面积2.23%。其中,滑坡灾害占总灾害的42%。评价结果与实际调查结果符合程度较高,能够为该地域未进行实地调查的地方进行相关滑坡灾害的预测预报,并对安全防治提供技术支持,亦可以为其他地区滑坡灾害危险性评价提供理论指导和技术参考。
文摘攀枝花市矿产资源丰富,采矿历史悠久,开采活动强度大,地质结构复杂,生态环境脆弱,矿山地质灾害频发.基于2019年的三江(怒江,澜沧江,金沙江)北段矿产开发环境遥感监测调查资料,在分析矿山地质灾害发育规律与影响因素关系的基础上,选取坡度、工程地质岩组、距断层的距离、降水量、植被覆盖度、距河流的距离以及距开采活动面的距离7个评价因子,借助ArcGIS软件平台,采用确定性系数(Certainty Factor,CF)模型、信息量模型以及CF与信息量耦合模型开展攀枝花市矿山地质灾害易发性评价研究.结果表明,工程地质岩组、植被覆盖度、距开采活动面的距离是影响矿山地质灾害分布的控制因子;经过ROC(Receiver Operating Characteristic Curve,ROC)曲线检验,CF与信息量耦合模型的AUC(Area Under the Curve,AUC)值高达0.909,表明耦合模型比单一模型的评价精度高,其精度为耦合模型>信息量模型>确定性系数模型;耦合模型的易发性分区为极高易发区(5.24%)、高易发区(11.67%)、中易发区(41.66%)和低易发区(41.43%),其中极高和高易发区主要分布在开采活动强度较大的煤矿、铁矿和花岗岩矿矿山,即主要分布在仁和区、东区、盐边县和米易县.
