论新疆深大断裂特征与地震的关系(3)   总被引：5，自引：0，他引：5  

宋和平 《内陆地震》2006,20(3):198-210

北天山山前地带是构造运动十分强烈的地区,褶皱断裂等构造现象十分发育,这里曾发生过多次中强破坏性地震。由于受区域构造长期作用的影响,在北天山山前地区逐步发育形成了多排褶皱背斜及活动断裂,且运动方式具有独特性。该区域作为推覆逆冲的典型地区,其研究成果具有代表性和普遍性。  相似文献   

黑龙江省山洪暴发气象条件及区划方法研究   总被引：1，自引：1，他引：0  

高煜中  王春丽  张桂华  潘华盛 《气象科技》2007,35(6):862-866

利用黑龙江省实际水文气象监测资料分析表明,山洪发生时空分布特征基本同全省暴雨分布相一致;山洪暴发前3h、24h、及前10天降雨量为有效关键时段,寒冷的气候条件,森林过度采伐对山洪暴发影响关系很大;特别是20世纪80年代以来黑龙江省气候明显变暖,暴雨次数也明显增多;根据山体滑坡、泥石流、土壤侵蚀的原理结合黑龙江省山洪发生特点,提出了山洪发生的概念模型及权重指标和山洪发生的等级。  相似文献   

Groundwater flow and storage processes in an inactive rock glacier          下载免费PDF全文

Jordan S. Harrington  Alexandra Mozil  Masaki Hayashi  Laurence R. Bentley 《水文研究》2018,32(20):3070-3088

Groundwater flow through coarse blocky landforms contributes to streamflow in mountain watersheds, yet its role in the alpine hydrologic cycle has received relatively little attention. This study examines the internal structure and hydrogeological characteristics of an inactive rock glacier in the Canadian Rockies using geophysical imaging techniques, analysis of the discharge hydrograph of the spring draining the rock glacier, and chemical and stable isotopic compositions of source waters. The results show that the coarse blocky sediments forming the rock glacier allow the rapid infiltration of snowmelt and rain water to an unconfined aquifer above the bedrock surface. The water flowing through the aquifer is eventually routed via an internal channel parallel to the front of the rock glacier to a spring, which provides baseflow to a headwater stream designated as a critical habitat for an at‐risk cold‐water fish species. Discharge from the rock glacier spring contributes up to 50% of basin streamflow during summer baseflow periods and up to 100% of basin streamflow over winter, despite draining less than 20% of the watershed area. The rock glacier contains patches of ground ice even though it may have been inactive for thousands of years, suggesting the resiliency of the ground thermal regime under a warming climate.  相似文献   

Drivers of peatland water table dynamics in the central Andes,Bolivia and Peru     

David J. Cooper  Jeremy Sueltenfuss  Eduardo Oyague  Karina Yager  Daniel Slayback  E. Marcelo Cabero Caballero  Jaime Argollo  Bryan G. Mark 《水文研究》2019,33(13):1913-1925

Cushion plant dominated peatlands are key ecosystems in tropical alpine regions of the Andes in South America. The cushion plants have formed peat bodies over thousands of years that fill many valley bottoms, and the forage produced by the plants is critical for native and nonnative domesticated mammals. The sources and flow paths of water supporting these peatlands remain largely unknown. Some studies have suggested that glacier meltwater streams support some peatlands, and that the ongoing loss of glaciers and their meltwaters could lead to the loss or diminishment of peatlands. We analysed the hydrologic regime of 10 peatlands in four mountain regions of Bolivia and Peru using groundwater monitoring. Groundwater levels in peatlands were relatively stable and within 20 cm of the ground surface during the rainy season, and many sites had water tables 40–90 cm below the ground surface in the dry season. Topographic and groundwater elevations in the peatlands demonstrated that the water source of all 10 peatlands was hillslope groundwater flowing from lateral moraines, talus, colluvium, or bedrock aquifers into the peatlands. There was little to no input from streams, whether derived from glacier melt or other sources, and glacier melt could not have recharged the hillslope aquifers supporting peatlands. We measured the stable water isotopes in water samples taken during different seasons, distributed throughout the catchments, and the values are consistent with this interpretation. Our findings indicate that peatlands in the study region are recharged by hillslope groundwater discharge rather than stream water and may not be as vulnerable to glacial decline as other studies have indicated. However, both glaciers and peatlands are susceptible to changing thermal and precipitation regimes that could affect the persistence of peatlands.  相似文献   

基于交通网络的乡村中小学优化布局     

陈玉龙  赖志柱  王铮 《地球信息科学学报》2020,22(5):1120-1132

合理规划中小学布局是优化教育资源配置、提高办学效益以及实现教育均衡发展的重要途径。本研究针对中国乡村建设的需要和中国多山的地理环境,考虑山地环境对乡村中小学选址的影响,构建多山环境下乡村中小学的区位模型,运用地理信息科学方法,以Visual Studio. Net 2010为开发平台,使用C#语言和ArcGIS Engine 10.0组件库,同时结合MATLAB编程,开发出基于交通网络的乡村中小学区位优化系统。最后将系统应用于贵州省某镇的小学布局优化中,分别在只考虑已有道路、假设道路可升级、假设道路可新建或升级3种情景下,通过改进的模拟退火算法,确定新建学校的最佳位置,以及新道路的修建和原有道路的升级情况,从而得到不同情景下各居民点学生的上学耗时。结果表明,交通网络对乡村中小学布局优化具有重要影响,改善交通网络条件能够有效提高学生的就学效率上学速度。  相似文献   

Climatic influences on forest fire and mountain pine beetle outbreaks and resulting runoff effects in large watersheds in British Columbia,Canada     

Margot E. Vore  Stephen J. Déry  Yiping Hou  Xiaohua Wei 《水文研究》2020,34(24):4560-4575

Many studies have defined the interrelationships between climate, forest disturbance, and runoff at small scales (<100 km²), but few have translated these relationships to large watersheds (>500 km²). In this study, we explore the relationship between climate, extreme forest fire seasons, mountain pine beetle (MPB) outbreaks, and runoff in eight large watersheds within the Fraser and Peace drainage basins in British Columbia (BC), Canada from 1981–2019. Using a climate index based on precipitation and air temperature anomalies, we find extreme forest fire seasons (those that burned >5% of a watershed's area) are most likely to occur when a warm/dry summer is preceded by multiple seasons of cool/wet conditions. Using the climate suitability class (CSC) model to explore the relationship between climate and MPB outbreaks, we validate previous findings that lower-than-average precipitation, warm growing season temperatures, and lack of extremely cold temperatures during winter are connected to MPB outbreaks within central BC. However, the CSC model needs improvements to accurately assess MPB suitability in northern watersheds that are located outside the model's calibration region, either through weighted variables or lower degree day thresholds. Minimal runoff response occurs from these forest disturbances, with the most prominent runoff change being related to the 2014 fire season in the Osilinka and Mesilinka watersheds. The limited effects of forest disturbance on annual runoff are likely related to large watershed sizes, low percentages of disturbed area in some study watersheds and post-MPB forest dynamics. These results provide valuable insight into the interrelationships of climate, forest disturbance and runoff in large Canadian boreal forested watersheds.  相似文献   

青海省互助县龙王山钼矿特征及控矿因素分析          下载免费PDF全文

郭林业 《甘肃地质》2010,(3):31-35

龙王山钼矿位于中祁连山中段加里东晚期龙王山黑云母二长花岗岩与寒武系中统碳酸盐岩接触带上,经矿床特征分析,属典型矽卡岩型钼矿。文章总结了矿床控矿因素、围岩蚀变及找矿标志,探讨了矿床成因。旨在为该区的找矿起到指导意义。  相似文献   

甘肃西部北山区断裂构造对地下水的控制作用     

尹政  赵艳娜  杨丽萍 《地下水》2010,32(3):12-14,98

甘肃西部北山区经历了多期构造运动,水文地质条件异常复杂,断裂构造严格控制着区内地下水的分布、埋藏及运动规律,主干断裂带与支干断裂的交汇部位、沟谷与断裂交汇带、新构造运动形成的沉降带及坳陷盆地等有利于地下水的赋存,可作为供水水源地水文地质勘探靶区。  相似文献   

四川省汶川地震极重灾区次生山地灾害分布规律与发育趋势   总被引：1，自引：0，他引：1  

韩用顺  朱颖彦  孔亚平  韩军  薛蛟  曾思美 《中国地质灾害与防治学报》2010,21(4):14-21

通过对汶川地震极重灾区次生山地灾害的实地考察、遥感调查和综合分析,阐述了次生山地灾害类型与特征,分析了次生山地灾害的时空分布规律,并结合灾害活动特性,探讨了次生山地灾害的发育趋势,提出了灾区防灾减灾和恢复重建的对策与建议。研究结果表明:(1)汶川地震在极重灾区诱发次生山地灾害逾万处,其分布具有点多面广、类型多样、成灾迅速、危害严重、监测预报困难等特点;(2)次生山地灾害的分布受地震烈度、地质构造、地形地貌、地层岩性的制约,并具有明显的滞后性和延续性;(3)利用GIS和遥感技术,能够快速有效地进行地震次生山地灾害的动态监测与灾情评估,从而为防灾减灾管理和灾后重建工作提供科学依据和借鉴参考。  相似文献   

北京山区工程勘察风险特征与防范措施研究     

吴言军  陈爱新 《中国勘察设计》2010,(10):45-49

北京山区工程地质条件复杂,岩土工程勘察中存在或潜在着诸多风险,能否全面查清山区工程建设场地的工程地质条件,认清风险影响因素,对工程建设的安全至关重要。识别风险源,有助于提高对勘察风险的理解和掌握。本文试对北京山区岩土勘察风险的主要影响因素进行分析,并提出对应的防范措施,希望能为北京山区工程建设安全提供一些参考和帮助。  相似文献