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黔东北地区是一个地质环境复杂的地区,地质灾害分布范围广、数量多,属于贵州省地质灾害高易发区域。为了深入研究地质灾害时空分布特征与孕灾地质环境规律,以黔东北地区沿河县为研究区,通过野外孕灾地质条件实地调查成果资料,结合历年地质灾害数据,详细阐述研究区内地质灾害分布的总体特征,总结地质灾害孕灾地质条件,深入分析各类孕灾因子对滑坡、崩塌等地质灾害发育的控制作用,通过综合分析研究区内孕灾地质条件,进一步将研究区划分为三大孕灾地质条件区,为减轻地质灾害风险、防灾减灾提供了科学依据。研究结果表明：研究区内地质灾害发生的时间受月平均降雨量影响十分显著;空间分布情况受地层岩性特征影响较大;区内地质灾害主要孕灾地质条件为地形地貌、地层岩性、斜坡结构等,降雨和人类工程活动为外部诱发因素;区内易滑地层主要为中志留统秀山组、下志留统龙马溪组、下奥陶统大湾组等;易崩地层主要为下奥陶统大湾组、下志留统雷家屯组、中二叠统茅口组;不同灾种的斜坡结构具有明显的差异性,滑坡主要发育于凹型和折线型斜坡,崩塌则多发育于凸型斜坡;研究区内地表水系与地质灾害发生具有一定关联性,区内乌江流域水系沿线200m范围内发生地质灾害数量占... 相似文献
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地质灾害的形成是多种因素综合作用的结果。阿图什市位于新疆维吾尔自治区西南部,由于受自然因素和人为因素条件的控制和影响,区内泥石流、崩塌灾害广泛发育,对研究区内的人身和财产安全构成严重威胁。因此,本文在地质灾害易发性定量评价模型建立的基础上,探讨了地质灾害定量评价空间数据库的建设和相关处理方法,并采用加权Logistic回归模型和证据权模型相结合大方式对阿图什市地质灾害的易发性进行了评价。 相似文献
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兰州是中国省会城市中地质灾害较为频发的地区之一,其地质灾害主要受地质、地形和人类活动等因素的影响。本文在分析兰州市区滑坡发育的控制因素和主要影响因素的基础上,以地理信息系统(GIS)为平台、采用专业数理统计软件SPSS中的逻辑回归模型(Binary Logistic)计算评价区内各单元格地质灾害的发生概率,通过GIS平台和SPSS软件之间数据格式的交换,利用GIS软件的空间分析功能,对兰州市滑坡灾害危险性进行了区划。研究结果与滑坡分布规律一致,对兰州市的地质灾害防治具有实际意义。 相似文献
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湖南桂东县大塘集镇属亚热带季风湿润气候区,主要分布剥蚀构造中山、低山地貌.本文在概述区内地质环境背景条件的基础上,较详细的阐述了区内地质灾害的主要类型及其基本特征,总结了地质灾害的形成条件.区内滑坡和不稳定斜坡等地质灾害的形成与地形地貌、岩土体工程地质条件、地质构造、水文条件以及人类工程活动等多种因素密切相关. 相似文献
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川藏公路然乌-鲁朗段位于雅鲁藏布江大拐弯北部,是地质灾害频发的地区,而地质灾害的发生受当地的地质、气候、水文、人类活动等多种因素的影响,其中地质条件是控制因素。研究区位于东喜马拉雅构造结北缘,是地质构造活动最强烈的地区。在地质构造上,东喜马拉雅构造结属于冈底斯、雅鲁藏布和喜马拉雅三个构造单元。区内构造的形成经历了3个时期7个阶段。川藏公路然乌-鲁朗段的地层属于冈底斯-念青唐古拉区中的拉萨-波密分区,第四纪冰碛发育。由于强烈的地质构造活动,区内断层、褶皱等构造发育,许多断裂仍在活动,尤其是嘉黎断裂。由于地质灾害的形成需要一定的条件,并受地质条件控制,因此区内地质灾害的分布具有明显的空间特征。 相似文献
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Rory N. Mortimore 《Proceedings of the Geologists' Association. Geologists' Association》2019,130(1):27-65
Late Cretaceous Chalk sedimentation history across the British Isles included (i) fault controlled uplift and subsidence in Northern Ireland and the Inner Hebrides and (ii) uplift along the lines of en echelon folds in Southern Britain and northern France. Synsedimentary slump folds and downslope displacement structures are compared with penecontemporaneous interbed slides and later tectonic folds and faults. Compressional strike-slip tectonic processes at Flamborough Head, Yorkshire, illustrate intra-Chalk slump beds in a half-graben setting. Progressive ‘growth’ of structures characterises early downslope slump folding, interbed sliding and some listric faulting. Sheet-flints replacing slide shear planes and early fractures provide evidence for early movements. Availability of open-slopes or the depth of burial under which the range of structures developed is reflected in the degree of disruption and fragmentation of chalk and flint. Fragmentation provides clues to the timing of events and origin of the Late Campanian Altachuile Breccia (Northern Ireland) and the Coniacian Hope Gap slides (Sussex). Fragmentation and formation of sheet flints together help distinguish intra-Chalk tectonics from Quaternary glacitectonic structures.The role of marl seams, high porosity chalk beds and hardgrounds on bed-sliding, décollement zones and disruption of chalk blocks from bedrock in glacitectonics is discussed. Chalk formations with marl seams develop a special style of fracturing related to early interbed sliding and pore-fluid escape structures. Marl-seams are shown to be primary sedimentary features and not the products of post depositional pressure-solution. More than any other formation the Late Santonian – Early Campanian Newhaven Chalk contains extensive sheet-flints and shows great lateral variation in thickness and lithology across the fold belts of southern England and northern France. 相似文献
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基于110口探井1 100 m岩心、500余口探井总长107 000 m火成岩井段资料,通过岩心观察、岩矿鉴定、物性测试和含油气性分析,研究了辽河坳陷东部凹陷新生界不同层系火成岩岩性、岩相发育特征和储层控制因素。结果显示：本区发育火山岩、侵入岩、沉火山碎屑岩3大类16种岩性,其中玄武岩类占91.0%;发育6相16种亚相,其中溢流相占63.0%;发育4类9种储集空间,次生孔隙和次生裂缝占主体。砾-粒间孔隙和裂缝发育的粗面岩类、玄武质火山碎屑（熔）岩和火山口-近火山口相带的侵出相、火山通道相和爆发相是最有利的储集岩性、岩相带。储层主要受岩性、岩相、断裂等多方面控制,岩性决定储集空间类型和储层微观特征,岩相控制储层宏观分布规律,断裂控制岩体分布范围、火山口位置和储层有效性。近油源、靠断裂的优势岩性、岩相带是火成岩油气勘探最有利目标。 相似文献
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中国南方早中三叠世岩相古地理 总被引：8，自引：0，他引：8
在各基于剖面的地层学及定量岩石学研究的基础上,采用单因素分析综合作图法,编制出了中国南方早中三叠世飞仙关期(印度期)、嘉陵江期(奥伦期)、雷口坡期(安尼期)和天井山期(拉丁期)的各种单因素基础图件及定量岩相古地理图。在这种古地理图中,各一、二、三级古地理单元的确定都有定量的单因素数据为依据。各期岩相古地理的特征可概括为陆海相间,台盆相间,台中有盆,盆中有台,台中有滩和坪,台盆间有斜坡。各期岩相古地理有明显的继承性和发展性。从早三叠世飞仙关期到中2叠世天井山期,是一个较大的海退过程。这种定量的岩相方地理图,为中国南方中下三叠统的油气勘探提供了科学依据。 相似文献
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新疆库车坳陷逆掩断裂在油气运聚中的作用 总被引：4，自引：0，他引：4
在研究新疆库车坳陷逆掩断裂、源岩和盖层空间发育特征的基础上,研究了逆掩断裂与源岩、盖层的空间匹配关系.认为断穿源岩、盖层的逆掩断裂则是油气散失的通道;勾通源岩,但未断穿盖层的逆掩断裂则是油气聚集的输导通道,它们控制着库车坳陷油气的聚散及其在空间上的分布.在研究库车坳陷逆掩断裂活动史和源岩排烃史、盖层封闭能力形成史的基础上,研究了逆掩断裂与源岩、盖层的时间匹配关系,认为盖层与源岩的时间匹配关系控制着可供运移的油气量;逆掩断裂与源岩的时间匹配关系控制着可供聚集的油气量,盖层与逆掩断裂的时间匹配关系控制着油气的富集量. 相似文献
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场地和断层对埋地管道破坏的影响分析 总被引：7，自引：3，他引：4
场地条件和断层活动是埋地管道破坏的主要原因,避免因为场地岩土和断层的影响而造成管道破坏,是城市地下生命线工程建设中急需解决的问题。采用ADINA软件的Parasolid建模方式,通过定义合适的体类型和布尔操作,建立了埋地管道破坏分析的几何模型,实现了土体－断层－管道破坏有限元建模。借助模型参数选择,确定了基岩与岩土性质、管道特性等模型参数;定义了管-土摩擦和约束条件、地震波和断层位移荷载等。依据计算结果,分析了场地条件和断层参数对地下管道地震破坏的影响;结果表明：管道埋藏越深,断层断距越大,管道的变形越大,破坏越严重。给出了管-土摩擦系数和断层与管道交角的最优值,并给出了几点工程建议。 相似文献
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Emma R. Power 《Geoforum》2009,40(6):1024-1032
Studies of domestic temporalities have emphasised the timing of social activities and interactions in the home, including how family members negotiate their use of home spaces and technologies, the impact of flexible work practices on home, and the organisation of care and mothering activities. But home is also shaped by the rhythms and times of nonhumans that inhabit, travel through and are part of the house-as-home; it is further shaped by the environment outside home. Drawing inspiration from recent discussions of nature times the paper explores the more-than-human temporalities of domestic space. It charts the ageing and decay of house structures, the disruption caused by nocturnal animals, and the seasonal cycles of sunlight and plant growth that immediately surround the home, attending to the ways that these events shape everyday experiences of home and homemaking. These times and rhythms are examined through interviews undertaken with people living with uninvited brushtail possums in the ceilings of their homes, interviews and diaries completed by new dog owners, interviews with gardeners, and analysis of popular Australian homemaking magazines. These stories emphasise the dynamic and unfolding nature of the house-as-home as a hybrid timespace produced through an ongoing entwinement of human and nonhuman, living and non-living, culture and nature. 相似文献
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H. P. Rossmanith K. Uenishi 《Fragblast: International Journal for Blasting and Fragmentation》2006,10(3):163-211
This contribution is the third part of a paper addressing size and boundary effects on explosively induced wave propagation, fracturing and fracture pattern development in small scale laboratory specimens, which are frequently used for model blast tests. Small cylindrical and block type specimens fabricated from concrete, sandstone and amphibolite are centre-line loaded by linear explosive charges and supersonically detonated. Using shock wave theory, elastic wave propagation theory, and fracture mechanics it is shown that the type of boundary conditions prescribed at the outer boundary of the cylinder controls the extension of stem cracking and the development of the fragmentation pattern within the body of the cylinder and the cube specimens. In the case of a composite specimen, where a cylindrical core of different material is embedded in a cylinder or in a cube, the level of fracturing and fragmentation is controlled by the conditions and possible de-lamination of the interface which, in turn, depends on the relative dimensions of the core and the block. Using known results from the theory of wave interaction with free boundaries and interfaces it will be shown that the fracture strain and the notch sensitivity of the material expressed by imperfections play an important role. Equally important is the ratio between the length of the pulse (space-wise or time-wise) and the characteristic dimensions of the models. Axi-radial boundary cracks and spalling will be explained on the basis of earlier wave propagation studies associated with supersonic blasting. Theoretical results are in good agreement with numerical simulations and recent experimental findings. 相似文献
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沉积盆地动力学研究的新进展 总被引：14，自引：2，他引：14
沉积盆地动力学研究在９０年代向多维、多角度、多种研究手段相结合的方向迈进。多维体现在盆地研究延拓至岩石圈层次、上部脆性变形与下部韧性变形相结合，造山带研究与盆地研究相结合，流变学、应力状态等随时间变化影响盆地动力学演化研究方面；同时，构造时间非线性因素也制约着盆地动力学历程。多角度体现在对制约盆地演化的热、应力与重力因素的综合研究，对盆地形成的热作用研究进一步加强，对岩石圈应力的时空演化与岩石圈形变对盆地动力学的影响有了深刻的认识，对重力的成盆作用有了新的探讨。多种研究手段如数值模拟、构造物理模拟实验以及二者的结合等已用来研究沉积盆地动力学演化。 相似文献
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Grain size and mineral composition of core sediments were used to investigate influences of various terrestrial and marine conditions, which have prevailed on the southwestern Black Sea shelf during the Holocene. Siliciclastic mud with small amounts of sand and gravel from nearby coastal hinterland is the principal sediment type, whereas sediments deposited near the shelf edge and the Istanbul Strait and off the Duru Lake （a paleo-river mouth） constitued large quantities of sand and gravel of both biogenic and terrigenic origin. Variable amounts of aragonite, 1 nmmicas, quartz, feldspars, calcite and dolomite constitute the dominant non-clay minerals in bulk sediments. The clay mineral assemblage in the 〈 2 μm fraction is made up of smectite, illite, kaolinite and chlorite. Aragonite and calcite are mainly derived from benthic accumulations, whereas feldspars （mainly plagioclase） and smectite reflect magmaticvolcanic provenance and the distribution of 1 nm-micas and chlorite correlate with nearby metamorphic sources onland. Nevertheless, grain size and mineral distribution generally indicate a combination of effects of wind and wave climate, longshore and offshore cyclonic currents, changing sea-level stands and nearby source rock and morphological conditions. It is also suggested that at least part of clay minerals could be derived from the northwesterly Danube River input. 相似文献
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作为流体作用过程中水—岩反应的产物，粘土矿物可以帮助人们认识水—岩反应的机制和流体活动的特征。本文以江西金山金矿为例，通过对热液蚀变粘土矿物伊利石和绿泥石结晶度、平均结晶大小和晶格应变的测定，讨论了岩石变形对伊利石和绿泥石结晶生长差异的影响。在岩石应变较弱、水／岩比较小的糜棱岩带，伊利石的平均结晶大小与结晶度成负相关，而在岩石应变较强、水／岩比较大的超糜棱岩带，绿泥石的平均结晶大小与结晶度成正相关。由应变较弱的蚀变糜棱岩带到应变较强的蚀变超糜棱岩带，伊利石的结晶度有变小的趋势，而绿泥石的结晶度则基本保持不变。认为在成矿流体作用过程中，粘土矿物的形成和特点不仅受水／岩比的影响，而且在岩石变形过程中，岩石的应变和恢复速率也影响粘土矿物的结晶大小；伊利石和绿泥石平均结晶大小与其结晶度之间的关系可以反映岩石变形的机制和行为。 相似文献