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51.
胡君春 《地下水》2014,(6):9-13
评价矿井充水特征和预测矿井涌水量是煤矿床水文地质勘查中一项重要和复杂的工作,不同矿区呈现出不同的水文地质特征,单方法预测矿坑涌水量风险较大,与实际出入甚远,应深入分析水文地质条件和矿床充水的各项因子,采用多方法预测矿坑涌水量。以云南省镇雄县坪上兴隆煤矿为例,分析研究水文地质条件和矿井充水特征,分别采用比拟法、地下水动力学法和回归分析法预测矿坑涌水量,为兴隆煤矿提供安全生产参考,也为矿区水资源开发和水环境保护提供依据。  相似文献   
52.
The Huanghebei Coalfield, one of the coal production bases in North China, was considered as a coalfield without coal‐bed methane (CBM) during past decades. In recent years, however, CBM has been discovered in coal‐bearing successions. In order to understand the CBM geological characteristics and accumulation process in this area, fifteen coal samples were collected and analyzed with respect to coal maceral and reflectance. The result shows that the gas distribution is uneven and the content varies in different areas even for the same coal bed. The storage of CBM is affected by geological factors such as burial depth, geological structures, and magmatic intrusion, among which the former two are more important in the formation of CBM. Deep burial of coal beds with the presence of cap‐rock mudstone can seal CBM. The CBM is also accumulated and preserved at the place where normal faults are distributed. Magmatic intrusion causes contact metamorphism and controls the CBM formation by heating the coal‐bearing successions. The obtained data indicate the geological conditions in northeastern Zhaoguan Mine are preferable for CBM formation and conservation; recent exploration estimates the CBM geological reserves up to 282.16 Mm3 and average of reserve abundance at 0.1662 × 108 m3 km?2. The Changqing Mine is a potential prospect in terms of CBM exploration since its geological conditions (structures and burial depth) are similar to the Zhaoguan Mine and its cap rock is even better.  相似文献   
53.
莱芜市煤炭和铁矿资源丰富,开采历史悠久,矿山排水量较大。煤矿矿坑水中SO42-、总硬度、矿化度、F-等组分较高,对地下水水化学场构成影响,矿区附近SO42-含量大于300 mg/L的孔隙水分布面积9.98 km2。铁矿排水具有高强度、大降深、强烈疏干的特征,导致矿山背斜东翼已形成水位降落漏斗,其中水位标高120 m的漏斗面积达27.5 km2,由于矿坑排水加之水源开采,1973年以来赵庄、孟家庄、西泉河地段共发生岩溶塌陷220处,塌陷总面积8 880 m2。  相似文献   
54.
济南张马屯铁矿安全生产30年,其根本保证是通过帷幕注浆建立起了一条长效稳定的地下“拦水大坝”。该技术不仅具有极高的安全效益和经济效益,同时具有保护地下水资源的社会效益。该项技术适用范围广、工艺成熟、易于实施,应该作为深井大水矿山地下水治理的主要技术方法予以推广应用。  相似文献   
55.
The paper describes the hydrogeological problems linked to the rehabilitation and re-utilisation of the water resources of the mining area of Gavorrano (Tuscany, Italy). It shows how the geological settings of the area control the water quality, chemistry and discharge. The results of the studies and the recent situations concerning circulation, quality and discharge of the mine water are reported, with particular reference to the effects of the controlled water rebound and the complex measures necessary for the dewatering stoppage. Water rebound is analysed on the basis of available historical and recent data for its hydrodynamic influence and the consequences on water resources restoration. Different uses and possible actions are proposed, taking into account thermal, chemical and discharge characteristics as well as local planning objectives.  相似文献   
56.
用卫星高光谱数据提取德兴铜矿区植被污染信息   总被引:24,自引:7,他引:17  
在深入分析研究德兴铜矿矿区植被光谱特征的基础上,利用美国EO-1卫星Hyperion高光谱数据,通过反演表征植物生理状态的光谱特征参数(红边位置和最大吸收深度)变异,提取与污染相关的信息,获取了矿山植被污染生态效应概况,为矿山污染的诊断和监测提供新技术和知识支撑。  相似文献   
57.
陕北风沙区位于毛乌素沙地东南缘,是毛乌素沙地向黄土高原的过渡地带,自然环境十分脆弱。本文通过对陕北风沙区大保当井田进行实地调查研究,结合遥感影像,运用图形叠置法、类比分析法和生态机理法分析了在该地区进行煤矿开采对当地自然植被、野生动物以及神木臭柏自然保护区的影响,并提出相应的生态保护措施。  相似文献   
58.
将地理信息系统(GIS)、数据库等技术运用到金属矿山安全生产中,设计并开发了基于GIS的金属矿山安全信息系统。本文重点阐述该系统的总体设计、数据库设计和核心功能实现。系统可进行地图管理、信息查询等基本操作和金属矿山的安全评价、事故预警,以及矿区地形的DEM分析,为金属矿山的安全生产提供科学指导。  相似文献   
59.
This paper presents the failure process of the external waste dump of the South Field Mine, the major open pit mine in Greece. The waste materials of the mine were deposited in three phases, forming an average inclination slope 10% and a total height of 110 m from the ground surface. The failure occurred when the third phase of the deposit was initiated. The high moisture content of the waste materials and their deposition over a spring, choking its flow, had as a result the development of high pore water pressure in clayey and marly materials in the base of the deposit. As a consequence, a large scale slope failure incident occurred. The landslide involved the mobilization of waste material in the order of 40 Mm3, while the material that moved outside the boundaries of the waste dump was in the order of 2.5 Mm3. The stability of the waste dump was investigated using the limit equilibrium analysis and different types of models.Limit equilibrium analyses were performed using different methods and considering the clay layer of small shear resistance that exists in the base of the deposit. They do not indicate activation of failure mechanism, only that there is a combination of high pore water pressure that developed in the deposit because the covering of the spring with the clayey materials of the dump.  相似文献   
60.
Mining wastes and calcines from two abandoned mining areas (Valle del Azogue and Bayarque in Almería) have been characterized. In the mining wastes, the dominant mercury phases are cinnabar and elemental mercury in the matrix. In the calcines, however, the dominant mercury phase is elemental mercury bounded to the matrix. Water-leaching experiments were conducted on low-grade stockpiles and calcines in order to simulate the mobilization of mercury by runoff under environmental conditions. The laboratory column-leaching experiments show a possible mobilization of mercury from Hg0 dissolution, colloid transport and a possible dissolution of calomel and other soluble phases in the mine wastes from the Valle del Azogue and Bayarque mines. Equilibrium speciation modeling of Hg, conducted using the numerical code MINTEQ, showed that the theoretical dominant mercury species in the calcine and mining wastes samples are Hg(OH)2, HgCl2, HgClOH and Hg0. In some leachates obtained from the Valle del Azogue mining wastes (sample A06), the high Hg concentrations may indicate the possible dissolution of mineral phases such as calomel and other soluble phases, which are subsaturated. The environmental results indicate a great environmental mobility of mercury, especially during wet episodes associated with intense precipitation events, when there are significative amounts of secondary soluble minerals.  相似文献   
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