浙江温州滑坡地质灾害预警方法及应用     

周明浪  邵新民  罗美芳 《中国地质灾害与防治学报》2014,(2):90-97

滑坡地质灾害预警方法主要有面状预警和点状预警两种,前者一般应用于国家级和省级层面上的预警,后者主要是针对具体的滑坡隐患点或者小范围地区。温州地区山区面积大,地形复杂,暴雨频繁,地质灾害频繁发生。温州滑坡地质灾害预警方法基本上采用面状预警理论,但是兼有点状预警的特色。其基本理论思想是：以近似于点状行政村为预警单元,实地调查典型的行政村,并全面收集有关地形、地貌、基础地质、历年地质灾害区划调查等资料,对每个预警单元（行政村）分析其发生滑坡地质灾害潜在能力的大小（潜势度）与灾害发生的降雨阈值,从而建立预警系统,并应用于政府在地质灾害防灾工作中。  相似文献   

兰州市皋兰山Ⅰ2滑坡稳定性分析及治理设计          下载免费PDF全文

王涛 《甘肃地质》2014,23(3):73-78

滑坡稳定性分析作为滑坡治理设计过程中一个关键的步骤,其计算方法的选择和计算结果的准确与否,直接关系到防治工程的安全可靠性、经济合理性和技术可行性等。以皋兰山Ⅰ2滑坡为实例,结合滑坡特征、滑动机理,对其稳定性进行分析、计算,并根据计算成果,进行了治理设计。  相似文献   

动水压力型滑坡对库水位升降作用的响应以三峡库区树坪滑坡为例   总被引：2，自引：0，他引：2  

向玲  王世梅  王力 《工程地质学报》2014,22(5):876-882

三峡库区涉水型滑坡众多,库水位周期性涨落引起库岸滑坡岩土体物理性质的改变,还使得滑体内渗流场发生变化,进而影响滑坡体稳定性。为研究库水位升降作用对涉水边坡稳定性的影响,基于三峡库区重大涉水滑坡分类,对动水压力型滑坡进行分析。以三峡库区秭归县树坪滑坡为例,利用Geo-Studio软件的SEEP模块及SLOPE分别对滑坡渗流场与稳定性进行计算,分析不同滑体渗透系数及不同库水位升降速率对动水压力型滑坡的影响规律。结果表明:对于动水压力型滑坡,库水位上升过程中,地下水位线有下凹趋势,稳定性系数有所增大; 库水位下降过程中,地下水位线有上凸现象,且稳定性系数明显减小; 库水位升降速率越大,滑体渗透系数越小,库水位变动对滑坡渗流及稳定性影响越明显。  相似文献   

折射法和高密度电法在古滑坡勘探中的应用     

葛军辉  李亚彬  赵祥阳  李建平  刘佳音 《世界地质》2014,33(3):665-670

古滑坡体地球物理调查方法技术的选择对勘探效果至关重要。以吉林省通化市拟建集安—通化高速公路滑坡体为例,采用折射波法和高密度电法,利用二维反演技术进行数据处理。结合地质信息,确定了滑坡体的形态及厚度变化,厚度最大约20 m,滑坡性质为堆积层滑坡。研究结果表明折射波法和高密度电法进行古滑坡勘探,效果较好。  相似文献   

基于统计数据的滑坡敏感性因子分析     

徐文刚  邱恩喜 《四川地质学报》2014,34(3):429-432

对奉节县老屋里滑坡进行滑坡敏感性因子分析,以滑坡的主轴断面为计算剖面,基于极限平衡法计算了滑体重度、滑带抗剪强度参数变化时滑坡的稳定系数,参数变化范围以大量的岩土统计参数值为依据。分别保持某一参数不变,作出其余二者与稳定性系数的关系曲线图,并固定一套参数取值方案,比较各参数随稳定性系数的变化趋势,最后得出敏感性分析结果。  相似文献   

Geochemistry,provenance and tectonic setting of the Late Cambrian–Early Ordovician Seydişehir Formation in the Çaltepe and Fele areas,SE Turkey     

Mehmet Muzaffer Karadağ 《Chemie der Erde / Geochemistry》2014

The major, trace and rare earth element (REE) contents of metapelite (MPL), metapsammite (MPS) and metamarl (MM) samples from the Cambro-Ordovician Seydi?ehir Formation were analyzed to investigate their provenance and tectonic setting. The MPS, MPL, and MM samples have variable SiO₂ concentrations, with average values of 72.36, 55.54, and 20.95 wt%, moderate SiO₂/Al₂O₃ ratios (means of 6.88, 3.23, and 3.80), moderate to high Fe₂O₃ + MgO contents (means of 5.14, 9.55, 3.56 wt%), and high K₂O/Na₂O ratios (means of 3.26, 3.64, 2.90), respectively. On average, the chemical index of alteration (CIA) values of the MPS and the MPL are 65.87 and 71.96, respectively, while the chemical index of weathering (CIW) values are 74.54 and 85.09, respectively. These data record an intermediate to high degree of alteration (weathering) of plagioclase to illite/kaolinite in the samples’ provenance. The chondrite-normalized REE patterns of all the sample groups are similar and are characterized by subparallel light rare earth elements (LREE)-enriched, relatively flat heavy rare earth elements (HREE) patterns with pronounced Eu anomalies (mean of 0.69) and moderate fractionation [average (La/Yb)_N = 8.7]. Plots of sediments in ternary diagrams of La, Th, Sc and elemental ratios (La/Sc, Th/Sc, Cr/Th, Eu/Eu*, La/Lu, Co/Th, La/Sc and Sc/Th), which are critical for determining provenance, and REE patterns indicate that the metaclastic units of the Seydi?ehir Formation were derived dominantly from felsic to intermediate magmatic rocks and not from a mafic source. The La–Sc–Th and Th–Sc–Zr/10 ternary diagrams of the Seydi?ehir Formation are typical of continental island arc/active continental margin tectonic settings. The geologic location and geochemistry of the Seydi?ehir Formation suggest that it was deposited in an Andean-type retroarc foreland basin during the Late Cambrian–Early Ordovician period. The Neoproterozoic intermediate to felsic magmatic rocks and metaclastic sediments with felsic origins of the Sand?kl?–Afyon Basement Complex (SBC) and their equivalent units, which are thought to be overlain by the younger units in the study area, may be the dominant source rocks for the Seydi?ehir Formation.  相似文献   

微型组合抗滑桩在青海西久公路某滑坡防治中的应用     

郭辉 《探矿工程》2014,41(5):46-49

使用微型组合抗滑桩结合其它工程措施治理滑坡是目前滑坡治理领域的一个新趋势,因其施工便利、压力注浆提高滑坡自身稳定性显著以及治理费用较低等优点,目前已大量应用于工程实践。以青海省西久公路某滑坡为例,在分析滑坡存在浅层和深层2个滑动带的基础上,提出采用微型组合抗滑桩结合锚拉式框架梁加固并使用仰斜排水孔的综合治理措施,通过治理后的稳定性验算和雨季暴雨的考验,证明了微型组合抗滑桩的综合措施的可行性和有效性。  相似文献   

顾及样本敏感性的滑坡易发性评价     

吕蓓茹  彭玲  李樵民 《测绘通报》2022,(11):20-25

滑坡作为一种危害极大的自然地质现象,严重威胁着人民的生命财产安全。因此,科学、准确地评价滑坡体的易发性至关重要。随着机器学习的发展,基于机器学习的滑坡易发性评价逐渐成为研究热点。而在真实情况中,滑坡区域与非滑坡区域面积占比悬殊,这使得机器学习模型的应用存在较严重的样本不均衡问题。本文采用样本敏感性分析方法,综合多个机器学习模型在不同比例的正负滑坡样本集上的表现,以获取最均衡滑坡样本集;并在此样本集基础上采用深度随机森林模型,在示范研究区开展滑坡易发性评价。最终的评价结果接近真实分布,表明本文方法具有较好的有效性。  相似文献   

地基SAR数据优化及灾变体面积预警预报分析     

刘玉溪  杨凤芸  秦宏楠 《测绘通报》2022,(12):51

针对地基SAR异常数据难以识别、潜在滑坡体发展特征及规律不明显、临滑面积估算难度大的问题,本文以甘肃某矿山滑坡数据为基础,介绍了地基SAR形变数据的处理方法,通过Matlab软件有效地识别、筛选、剔除了异常形变数据,并以色彩差异进行区分,进一步突显了不同阶段潜在灾变体面积的演化规律。基于地基雷达监测原理,提出一种多边形面域估算方法,实现潜在危险区域面积的估算。研究不等周期处理的速度倒数曲线组,发现速度倒数平方法能够进一步放大特征趋势,预测结果准确、预报效果好,为实现矿山滑坡超前预警预报提供了新的思路。  相似文献   

The Impact of an Abnormal Zonal Vertical Circulation in Autumn of Super El Ni?o Years on Non-tropical-cyclone Heavy Rainfall over Hainan Island     

Fei WANG  Lifang SHENG  Xiadong AN  Haixia ZHOU  Yingying ZHANG  Xiaodong LI  Yigeng DING  Jing YANG 《大气科学进展》2022,39(11):1914-1924

This study reveals a significant positive connection between autumn non-tropical-cyclone heavy rainfall on Hainan Island and the intensity of Eastern Pacific (EP) El Ni?o events. That is, the amount of rainfall in super EP El Ni?o years is more than that in normal EP El Ni?o years. Comparing EP El Ni?o years of different intensities, the cooler sea surface temperature in the northwestern Pacific during super EP El Ni?o years stimulates a negative surface latent heat flux (LHF) anomaly and abnormal anticyclonic circulation at 850 hPa. Under these conditions, an abnormal zonal vertical circulation develops in the northern South China Sea once a positive LHF anomaly and abnormal cyclonic circulation (ACC) at 850 hPa occur in the Beibu Gulf. The abnormal zonal vertical circulation further strengthens the ascending motion over Hainan Island, as the critical factor that leads to excessive rainfall. Further analysis shows that the positive LHF anomaly, which can be attributed to the increased latent heat transfer which resulted from the increased surface wind speed, is an important trigger for the ACC. However, the ACC is also the supplier of favorable moisture conditions because it intensifies vapor convergence over Hainan Island and meridionally transports moisture from the South China Sea to northeastern Hainan Island, thereby generating heavy rainfall. This paper emphasizes that the impact of El Ni?o events, especially super El Ni?o events, on rainfall over Hainan Island cannot be ignored, even if the traditional view is that frequent rainfall occurs mainly in La Ni?a years.  相似文献