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1.
压性断裂在我国褶皱山区有着广泛的分布。如秦岭大巴山的压性断裂就相当发育,其延伸长度往往与褶皱长度相差无几。南岭纬向构造带的西段(尤其是西北端),川滇经向构造带的中段和南段也都是以压性断裂为主要构造形迹:龙门山褶皱带中的压性断裂也与其同向褶皱紧密伴随,成为该区级别最高的主干断裂。对这些地区,正确判断压性断裂的导水部位与导水性,在确定找水方向、评价地下水资源、合理开采地下水,以及对矿山排水、边坡稳定、水库渗漏进行预测等方面都具有重要意义。  相似文献   

2.
内蒙古维拉斯托锌铜矿床地质特征及成因探讨   总被引:1,自引:0,他引:1  
屈强  李云刚 《西部资源》2013,(2):74-75,86
内蒙古维拉斯托锌铜矿床位于大兴安岭西坡成矿带上,燕山早期花岗岩外接触带附近断裂为成矿有利部位。北西向张扭性断裂为成矿提供了良好的矿液运移通道,近东西向压扭性断裂为成矿物质的充填、沉淀提供了良好的空间,矿体赋存空间即为断裂构造,严格受构造控制。维拉斯托矿区锌铜多金属矿围岩为黑云斜长片麻岩及花岗闪长岩,矿床的形成为断裂构造控制的中高温热液。  相似文献   

3.
朱楼勘查区位于安徽省砀山县,勘查区为全隐伏式井田。本区主体构造形迹的形成,主要受东部郯庐断裂的影响。由于郯庐断裂的左行平移和南北古地块及其附近东西向断裂的联合作用形成了北部收敛,南部撒开的徐淮弧形褶皱束,构成了本区基本构造格架。区内褶皱、断裂构造简单,通过对该区历年施工钻孔资料的整理和分析研究,认为区内地质构造对煤层的形态和分布有控制作用。通过对该区地质构造特征的研究,根据本区地质、构造等实际情况。为以后工程布置、矿山开采提供依据。  相似文献   

4.
矿区位于雷公山复式背斜西翼,野记断裂带旁侧。褶皱平缓开阔,呈长条状构造线大都呈南北向、北北东向,与褶皱相伴生的南北向、北北东向断裂极为发育,大多是压性、扭性断裂,它们直接或间接地控制区内铅、锌、汞、金的成矿地质条件及矿产的分布规律。本文对矿区地层、构造、围岩蚀变、矿床地质特征及矿石结构、构造进行详细分析,进而对矿床成因及找矿标志进行深入研究,研究结果对矿区以后的地质勘查及生产具有很重要的参考作用。  相似文献   

5.
张冲  孟维峰 《西部资源》2014,(2):130-132
内蒙古自治区东乌珠穆沁旗海勒斯台陶勒盖铅锌矿区查明资源量(333)+(334?)铅锌矿石量159.53万吨,铅锌金属量为38,201.42吨,伴生银金属量9.344吨。矿石平均品位为锌1.90%、铅0.21%,伴生银18.56g/t。综合地质、物化探异常特征分析该矿床为含矿热液灌入控矿构造后而形成的火山热液型矿床,成矿围岩是志留系上统卧都河组板岩。主要控矿构造是近北东向的压扭性断裂带,控矿的主要条件是断裂构造,矿床成因类型为中低温火山热液型矿床。  相似文献   

6.
南迦巴瓦峰地区的地质构造分属喜马拉雅构造带、雅鲁藏布江构造带及冈底斯构造带,三者性质截然不问。不同构造单元的岩层、构造运动和构造系统都有差别,它们无论是在空间分布上,还是在地质演变历史上,彼此交汇复合,显得十分复杂。  相似文献   

7.
沪蓉高速公路西段线路工程地质遥感解译   总被引:3,自引:0,他引:3  
沪蓉高速公路西段路线走廊带是我国西南喀斯特生态环境脆弱区,喀斯特发育,存在一些重要的不良地质现象,如喀斯特地面塌陷和滑坡。该区在长期地壳运动发展中,不同时期、不同规模、不同方向的断裂构造体随时间、空间(构造位置及边界条件)和构造运动方式的变化,在各种地应力场的作用下形成了不同性质、不同规模等级的线性构造形迹。在沪蓉高速公路西段勘察中,利用空间图像的光谱特征和几何图形特征,探讨遥感解译过程中对各类线性构造分布及其特征的识别、判别工作方法与流程。  相似文献   

8.
中国东部大同火山群发育的构造地貌背景   总被引:6,自引:0,他引:6  
大同火山群是我国东部重要独特地貌类型之一。火山群及其所在的大同盆地位于上地幔隆起带上,受中国东部最突出的构造地貌格局——NNE向雁行右旋剪切拉张断陷带控制。火山群及熔岩溢出带即明显沿着这个右旋剪切拉张破裂带以及与NW压扭性断裂交汇处发育,同时受到断裂多次活动的影响。  相似文献   

9.
通过对山西西山煤田古交矿区断裂构造分布特征、构造组合以及力学性质等方面综合分析,对矿区断裂构造发育规律及其构造演化特征进行了研究。研究认为:区内断裂构造主要为NEE、NNE向高角度正断层,断裂构造的发育具有明显的分区性、分带性以及等距性特征,组合形式主要为雁列式展布、堑垒相间型、阶梯状以及"Y"字形构造组合。矿区主体构造的形成演化主要经历了燕山早期、燕山中~晚期、喜马拉雅期三个阶段,造就了井田现今的构造格局。  相似文献   

10.
黄琼芳 《热带地理》2016,36(6):935-943
广东省共有丹霞地貌 67 处,分布在 22 个断陷盆地中,主要受古近纪―新近纪抬升区、5 条北东向深大断裂和 1 条东西向深断裂控制,地层层位以丹霞组和南雄群为主,岩性以砾岩、砂砾岩、砂岩为主。古近纪―新近纪地壳升降运动控制了丹霞地貌在区域上的总体分布,大致以 22.5°N 为界线,以北为抬升区,发育丹霞地貌,以南为沉降区,不发育丹霞地貌;晚更新世以来的地壳升降运动,造成不同地区丹霞地貌的数量和规模有所区别:粤北、粤东北为抬升区,发育数量多、规模较大;粤中为沉降区,发育数量少、规模较小。深大断裂控制断陷盆地的分布,从而控制丹霞地貌具体的发育位置。根据地质构造背景和丹霞地貌发育特征,可将广东省划分为 4 个丹霞地貌发育区:粤北区、粤中区、粤东北区和粤西区。  相似文献   

11.
This paper problematises positivist framings of water demand management (WDM) that define the average‐water‐user. Through a situated, case‐study account undertaken in suburban Auckland, we highlight variable social and cultural underpinnings of domestic water use. Activities that are commonly the focus of WDM are shown to be embedded elements of life around which relationships, affects and futures are woven. As a consequence, myopically focusing on the technical–managerial mediation of what are socionatural relations reduces prospects to achieve intended policy outcomes. Reframing WDM as a hydrosocial process provides a basis for water providers to develop more culturally appropriate water management.  相似文献   

12.
以色列水足迹及其对我国西北干旱区的启示   总被引:1,自引:0,他引:1  
水足迹作为一个综合的指标,揭示了一个国家或地区的总需水量,可以粗略地衡量人类消费对自然水环境的影响,为干旱缺水地区水资源合理开发利用、高效配置提供了一个新视角。本文分析了以色列1999年的人均水足迹、总水足迹及其组成,其总水足迹为8.58×10^8m^3m^3,是可更新水资源的4.77倍;人均水足迹为1391m^3/人/年,是人均水资源占有量的3.76倍,并探讨了以色列水足迹对我国西北干旱区的启示。  相似文献   

13.
黄河孟花段水环境质量评价   总被引:5,自引:1,他引:5  
针对黄河泥沙对水环境质量评价的突出影响,为了完整地反映多泥沙河流的水环境质量状况以及有效区分由泥沙带来的自然污染与由污染物排放引起的人为污染,该文依据多泥沙河流水环境质量评价应遵循的基本思想方法,对黄河孟花段的水环境质量状况进行了评价。  相似文献   

14.
The Arab region covers an area over 13 million square kilometers in size, with almost 90% of its area classified as arid or extremely arid with very little precipitation, extremely high evaporation and almost no vegetation cover. The region is classified in many international reports as the poorest region in the world in the context of renewable water resources and critical water scarcity which hinders the socio-economic development of many countries in this region. The rapidly increasing population has reduced the per capita share of renewable water to less than the poverty line of 1,000 m 3 /(capita·a) and, in some Arab countries, to less than the extreme poverty line of 500 m 3 /(capita·a). This has led to over-exploitation of non-renewable groundwater and desalination of salty water in many countries with considerable costs and contamination of many renewable sources. Atmospheric processes responsible for aridity in the Arab region are projected to intensify due to climate change, resulting in an alarming decrease in precipitation and increase in evaporation rates. Many concerned entities in the region consider water security as a key element for food security and ultimately political stability. Hence, various efforts have been exerted to identify key problems and suggested solutions. The Arab Water Ministers Council of the Arab League, as well as Reports of the Arab Forum for the Environment and Development (AFED) and the recommendations of the 13th Regional Meeting of the Arab National Committees of the International Hydrological Programme of UNESCO (IHP), have all made similar recommendations on the need to address the issues of water scarcity in the Arab region which will be further discussed in this paper. However, none of these reports focused on "Water Conservation" as an equally important action for coping with water scarcity in the region. There are many definitions for "Water Conservation" in the scientific literature, including huge water savings from irrigation, industrial use, and domestic use as well as methods and approaches for augmenting water supply through non-conventional practices such as water harvesting and waste water reuse. In this paper, a review is provided for definitions, methods and impacts of water conservation and its role in alleviating water scarcity in the Arab region.  相似文献   

15.
淮河(安徽段)南岸诸河流水质标识指数评价   总被引:1,自引:0,他引:1  
韩曦  王丽  周平  孙庆业 《湿地科学》2012,10(1):46-57
2010年夏季,对淮河(安徽段)南岸诸河流水质进行调查,共设置采样点160个,选取总氮、总磷、氨氮和化学需氧量4项水质指标,利用综合水质标识指数评价法(WQI)对淮河(安徽段)南岸诸河流水质进行评价。结果表明,淮河(安徽段)南岸诸河流水质达标率77%,超标的评价因子为氮营养盐和化学需氧量。污染物主要来自农业面源和生产、生活废水;水流流速、沉积物性质和周围环境对水质产生一定影响。  相似文献   

16.
Oases in arid northwestern China play a significant role in the region's economic stability and development. Overexploitation of the region's water resources has led to serious environmental consequences. In oases, irrigated agriculture is the primary consumer of water, but water shortages resulting from dramatically growing human needs have become a bottleneck for regional sustainable development, making effective management of the limited available water critical. Effective strategies must be formulated to increase agricultural productivity while reducing its environmental impacts. To support the development of such strategies, water use patterns were analyzed during the 2007 and 2008 growing seasons, from May to early October, to identify opportunities for improving water management using the Molden-Sakthivadivel water-accounting method, which combines groundwater and surface water into a single domain and can provide a good estimate of the uses, depletion, and productivity of water in a water basin context. The study area lies in Linze County, Gansu Province, China. In the study area, the inflow water resources consist of irrigation, precipitation, and soil water, which accounted for 89.3%, 8.9%, and 1.8% of the total in 2007, and 89.3%, 4.8%, and 5.9% in 2008, respectively. The irrigation depends heavily on groundwater, which accounted for 82.1% and 83.6% of the total irrigation water in 2007 and 2008, respectively. In 2007 and 2008, deep percolation accounted for 50.1% and 47.9% of the water outflow, respectively, with corresponding depleted fractions of 0.51 and 0.55, respectively. For the irrigation district as a whole, the water productivity was only 1.37 CNY/m3. To significantly increase crop water productivity and prevent depletion of the region's groundwater aquifer, it will be necessary to reduce the amount of water used for irrigation. Several water-saving agricultural practices are discussed and recommended.  相似文献   

17.
胡家权  庞洪喜 《极地研究》2018,30(2):210-219
系统地介绍了低温冷阱大气水汽收集的基本原理、实验方法、实验过程中的误差估计以及该方法在水稳定同位素研究中的应用。基于低温条件下显著增加水汽凝结面和凝结时间的方法,使水汽完全凝结;利用水分在真空条件下升华/蒸发及其在低温条件下再凝结的原理,实现对水汽样品的转移收集。收集的水汽样品中稳定同位素值的误差主要来自两方面:(1)低温条件下玻璃冷阱中部分未冷凝的饱和水汽;(2)样品室温融化后,外界大气进入瓶内与融化后的水汽样品发生同位素平衡分馏;并分别对上述两种误差进行了理论估计。利用低温冷阱水汽收集和稳定同位素离线测试方法在以下三方面具有较重要的应用:(1)过量~(17)O是当前水稳定同位素研究的前沿,实现对大气水汽中过量~(17)O高精度测试是该方法的重要应用;(2)获取低水汽浓度地区高精度大气水汽稳定同位素测试数据;(3)验证激光光谱稳定同位素分析仪在线水汽稳定同位素测试数据。  相似文献   

18.
Global and Regional Water Availability and Demand: Prospects for the Future   总被引:1,自引:0,他引:1  
One of the most pressing global issues currently facing mankind is the increase in world population and its impact on the availability of freshwater. Recent estimates of water stocks and flows through the world's hydrologic cycle and their spatiotemporal variability illustrate the nature of current and projected water disparities throughout the world. As all such problems manifest themselves at smaller scales, a major challenge in freshwater assessments is how to handle this on different geographical scales. Increasing use of water is creating water shortages in many countries that are projected to have significant population increases in the next 25 years. Humankind is projected to appropriate from 70% to 90% of all accessible freshwater by 2025. Agriculture is the dominant component of human water use, accounting for almost 70% of all water withdrawals. Hence, many of the solutions to water-related food and environmental security come from within agriculture by increasing the efficiency and productivity of water use. Many factors significantly impact the increasing water demand, including population growth, economic growth, technological development, land use and urbanization, rate of environmental degradation, government programs, climate change, and others. Demand management, not increasing supply availability, is the realistic way forward. Although, thanks to market forces, the threatened exhaustion of nonrenewable resources has not happened, renewable resources, such as freshwater, remain problematic because they are vulnerable to human overuse and pollution. Climate change adds further risks and uncertainties to the global picture requiring the adoption of adaptive management in water resources based on monitoring and reevaluation. Although climate change may be perceived as a long-term problem, it needs to be addressed now because decisions today will affect society's ability to adapt to increasing variability in tomorrow's climate. If we are to balance freshwater supply with demand, and also protect the integrity of aquatic ecosystems, a fundamental change in current wasteful patterns of production and consumption is needed. Recognition of the links between rapidly growing populations and shrinking freshwater supplies is the essential first step in making water use sustainable.  相似文献   

19.
水空间管理与水资源的可持续性   总被引:26,自引:12,他引:14  
邓伟  翟金良  闫敏华 《地理科学》2003,23(4):385-390
水资源的赋存需要特定的空间结构,水空间对于维系水资源系统的完整性、保障水循环和水资源的可再生能力、实现水资源的可持续开发利用具有重要作用。 由于人类活动极大地干扰了地球表层系统,水空间结构遭到严重破坏,破坏了水资源支撑社会经济发展的可持续能力。水空间的丧失极大地改变了流域尺度上的水循环过程,加剧了水资源的负均衡性。科学规划水空间,建立水资源安全的水空间格局和预警系统,以实现水资源的可持续性利用,保障资源、环境与社会经济协调发展。  相似文献   

20.
As the consequence of climate change, water that is received in Australian Murray-Darling Basin wetlands is declining and agricultural water demands are increasing. In order to keep the water use balance between environment protection including wetland protection and irrigation water use, the Australian government adopted a series of reforms in Murray-Darling Basin to address the environmental water shortage problem and encourage irrigators to use water more efficiently and plant high economic value crop. The water trading and cap are two major reforms in this process.In order to match up the environmental water demand such as wetland water use, based on the seasonal rainfall, dam level and environmental water demand, the cap system seasonally allocate how much water the irrigators can access as per water licenses. As the cap dramatically reduced the water access for irrigators, the water trading is aiming to use limited agricultural water more efficiently. The water trading scheme separate the water use right from the land property right and allow Australian farmers to trade their water licenses in the market. Water trading encouraged farmers who plant low value crops such as wheat and canola transfer their water entitles to farmers who plant high value crops such as grape. In the drought seasons, The Australian government can purchase the water licenses from irrigators to increase the environmental flows.This Australian water management system represents the most complicated and effective environmental and agricultural water use management in this world. There are possible many lessons that will help China to better manage the water use for wetland protection and farming practices.  相似文献   

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