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Drilling information, historical water table levels, groundwater salinity records of the existing water wells in Wadi Al Bih area, United Arab Emirates, were stored in a geodatabase and used to characterize the geological and hydrogeological settings of this area. A 2D earth resistivity imaging survey was conducted for the first time in the Northern UAE to determine the potential of the Quaternary aquifer and its groundwater quality in the areas where there are no monitoring wells. The results of the chemical analyses of the collected groundwater samples together with the inversion results of the resistivity data were used to draw a total salinity map and determine the spatial variations in groundwater quality. The inversion results of the 2D earth resistivity imaging data indicated that the Quaternary aquifer in the study area is in a good connection with the underlying carbonate aquifer. It also indicated that the carbonate aquifer is of major regional and vertical extension and it contains the fresh water in this area. The data stored in the developed database were used to produce different types of geopotential maps.  相似文献   
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The present study was carried out in Singrauli area of the north India to know the water quality at selected sites. Physico-chemical parameters like pH, total dissolved solids (TDS), bicarbonate, hardness, calcium, magnesium, sodium, potassium, chloride, sulfate, copper, iron, cobalt, manganese, zinc, and chromium were analyzed in 27 water samples. Locations selected for sampling were based on the preliminary field survey carried out to understand the overall impact of mining and industrialization on the surface and groundwater resources of Singrauli. Base map, drainage map, and land use/land cover of the study area were prepared from Survey of India topographic map 63 L/12 on 1:50000 scale and satellite data of IRS P6 LISS III 4th May 2010. Land use were categorized into 15 categories out of which major area occupied by open forest covers 20.33 %, uncultivated land 20.25 %, cultivated land 12.60 %, dense forest 11.00 %, and other categories cover 35.82 %. The results obtained are compared with World Health Organisation standards for drinking water quality. The physico chemical analysis shows alkaline nature of water, soft to moderately soft, TDS and total alkalinity exceeds the desirable limit. The major ions in water like calcium, and magnesium are within desirable limits, and sulfate and potassium exceed in limit at some locations, whereas sodium and chloride show higher values. The minor ions like copper and zinc show values within desirable limits whereas iron, cobalt, and chromium show higher values than the desirable limits which deteriorate the quality of water.  相似文献   
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The remotely sensed data provides synoptic viewing and repetitive coverage for thematic mapping of natural resources. In the present study hydrogeomorphological mapping has been carried out in Kakund watershed, Eastern Rajasthan for delineating groundwater potential zones. IRS-1D LISS III Geocoded FCC data in conjunction with Survey of India toposheet (1:50000 scale) and field inputs were used for thematic mapping. Geomorphic units identified through visual interpretation of FCC include: alluvial plain, plateau, valley fills, intermontane valleys, burried pediment, residual hills, and linear ridges. In addition, lineaments were mapped since they act as conduit for groundwater recharge. Majority of the lineaments trends NE-SW and a few along NW-SE directions and are confined to the southern and southeastern parts of the watershed. Based on hydrogeomorphological, geological and lineament mapping the Kakund watershed has qualitatively been categorized into four groundwater potential zones, viz. good to very good, moderate to good, poor to moderate and very poor to poor. The study reveals that only 10.97% of the area has good to very good, 35.41% area with moderate to good, 49.04 % of the area has poor to moderatel, while remaining 4.57% has poor to very poor groundwater potential.  相似文献   
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Ancient subduction zones are characterized by metamorphic and orogenic belts. The Zagros Orogenic Belt comprises almost all sections of an ancient subduction zone along which Neo-Tethyan oceanic crust was subducted beneath central Iran. The Eslami Peninsula, as a part of the Zagros Orogenic Belt in Azerbaijan province, northwestern Iran, is situated between the Lake Urmia fore-arc basin and the Sahand Magmatic Arc. This region contains Eocene leucite dikes, trachyte, tephrite, phenolite, basanite and syenite. Volcanic features related to the Sahand are located in the eastern part of the Eslami Peninsula. In view of its relative age and composition, the Eslami Peninsula proposed as an outer arc of the Sahand Magmatic Arc that formed within the post-collisional setting of the central Iranian and Arabian plates. After subduction and contact of the two plates, a symmetric pop-up structure has been created by thrusting in the Zagros belt as a result of the collision processes. The injesction of dikes in the Eslami Peninsula is also a result of the continent_continent collision.  相似文献   
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Analytical solutions are presented for transient water-table profiles in finite unconfined aquifers due to infiltration occurring from a single canal or more than one canal. The aquifer boundaries are assumed to be parallel to the alignment of the canal(s) and the lower impervious bottom is horizontal. Further, the aquifer is assumed to be homogeneous and isotropic. Losses such as evapotranspiration are ignored; likewise replenishment from other sources, for example, rainfall, is also neglected.  相似文献   
37.
Cold-water coral ecosystems represent unique and exceptionally diverse environments in the deep-sea. They are well developed along the Irish margin, varying broadly in shape and size. The Moira Mounds, numerous small-sized mounds, are nestled in the Belgica Mound Province (Porcupine Seabight, North-East Atlantic). The investigation of living (Rose Bengal stained) and dead benthic foraminiferal assemblages from these mounds allowed to describe their distribution patterns and to evaluate their response to environmental variability. Quantitative data was statistically treated to define groups of species/genera associated to specific habitats. The Moira Mounds differ from their larger neighbours by the reduced spatial variability of benthic foraminiferal assemblages, living assemblages only distinguishing coral-rich and coral-barren areas. The ecological needs of corals are highlighted by the abundance of Alabaminella weddellensis and Nonionella iridea, phytodetritus-feeding species in coral supporting sediments. Living foraminifera in sediments from the Moira Mounds concentrate in the upper first centimetre. Infaunal species may be affected by bioturbation and/or reworking by the strong currents in the area. Dead foraminiferal assemblages from the Moira Mounds resemble those described for the sandwave facies in adjacent giant mounds, suggesting similar processes in facies deposition.  相似文献   
38.
Boota  Muhammad Waseem  Yan  Chaode  Abbas  Tanveer  Li  Ziwei  Dou  Ming  Yousaf  Ayesha 《Natural Hazards》2021,109(2):1387-1405
Natural Hazards - Prediction of the flash floods in ungauged or poorly gauging watershed is one of the challenging tasks in the field of hydrology and needs implication of advanced techniques to...  相似文献   
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This study presents a detailed geological and geotechnical analysis of Dewal landslide along Murree-Muzaffarabad road, Pakistan. The study area is situated in a tectonically active region of the earth where mass movements like rock fall, rockslides and slumps cause adverse economic loss through disruption of travelling on roads. The study has the main focus on factors responsible for its instability together with stability analysis using limit equilibrium method by use of computer program Slide (version 5.0). The input parameters of rock mass was evaluated by field investigations and laboratory testing. To analyze the net deposit and net slide mass of the landslide area, multi-date point’s data of 2008 and 2012 of the slide area was obtained and their digital elevation models were generated by using Inverse distance weighting (IDW) technique in ArcGIS 9.3. The study has concluded that the present slope instability is the function of a specific deformation pattern in the rock units (leading towards the possibility of a shear plane under the slid mass), surface and subsurface drainage and the engineering behavior of the overburden and underlying rock units. This study recommends several protection parameters for landslide and suggests that detailed investigation of Dewal landslide is required for long term stability.  相似文献   
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