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91.
The Kemalpa?a Basin is one of the Quaternary basins in Western Anatolia and represents the south-western branch of the Gediz Graben system in this extensional province. This basin has been formed under the NNE–SSW trending extensional tectonic regime. It is bounded by a major fault, the Kemalpa?a Fault, in the south and it is bounded by a number of downstepping faults, called as Spilda?? Fault Zone, in the north. Both margin-bounding faults of the Kemalpa?a Basin are oblique-slip normal faults. In order to better understand the activities of these faults, we investigated the tectonic geomorphology of the Kemalpa?a Basin and interpreted the effect of tectonic activity on the geomorphological evolution using geomorphic markers such as drainage basin patterns, facet geometries and morphometric indices such as hypsometric curves and integral (HI), basin shape index (Bs), valley floor width-to-height ratio (Vf) and mountain front sinuosity (Smf). The morphometric analysis of 30 drainage basins in total and mountain fronts bounding the basin from both sides suggests a relatively high degree of tectonic activity. The mountain front sinuosity (Smf) generally varies from 1.1 to 1.3 in both sides of the basin suggesting the active fronts and facet slopes (12°–32°) suggest a relatively high degree of activity along the both sides of the Kemalpa?a Basin. Similarly, the valley floor width-to-height ratios (Vf) obtained from the both sides indicate low values varying from 0.043 to 0.92, which are typical values (<1) for tectonically active mountain fronts. The all values obtained are lower for the southern side. Therefore, we suggest that the tectonic activity of the Kemalpa?a Fault higher than the Spilda?? Fault Zone. This difference that can be arised from the different uplift rates also reveals the typical asymmetric characteristics of the Kemalpa?a Basin. Additionally, the trapezoidal facets which have been observed on the southern side of the basin indicate that the Kemalpa?a Fault is evolutionally more active as compared to the Spilda?? Fault Zone. The geomorphic indices indicate that the Quaternary landscape evolution of the Kemalpa?a Basin was governed by tectonic and erosional processes, and also the all results of morphometric analysis suggest a relatively high degree of tectonic activity along the faults bounding the Kemalpa?a Basin. Moreover, considering that active large normal faults with an average 15 km long can cause major earthquake, the earthquake hazard in the Kemalpa?a Basin should be investigated in detailed paleoseismological studies.  相似文献   
92.
No detailed information has previously been available on the geological and geophysical characteristics of the sea floor and the underlying strata of Mersin Harbour, Northeastern Mediterranean Sea (Turkey). Continuous resistivity profiling (CRP) and borehole data from Mersin Harbour were used to interpret geoelectric stratigraphy of Neogene-Quaternary sediments in the area. This represents one of few such detailed case studies that have applied these valuable CRP techniques for the purpose of marine stratigraphic imaging. It was found that the Neogene-Quaternary sedimentary succession in the area consists of three geoelectric units (GU1, GU2, and GU3 from base to top). The lowest unit, GU1, has a resistivity value of greater than 20.0 ohm-m and consists of Miocene aged limestone and marl. The middle unit, GU2, is characterized by resistivity values ranging from 3.0 to 20.0 ohm-m. Its thickness is greater than 90 m, with the upper section being composed of stiff clay sequences which are Plio-Pleistocene in age. The uppermost unit, GU3, has resistivity values varying from 1.0 to 3.0 ohm-m. This unit displays a maximum thickness of 15 m, and is composed of Holocene muds together with gravel, sand, silt and clay (sometimes incorporating shells) materials of the Plio-Pleistocene age and their various mixtures, silty/clay limestone, and conglomerate sandstone. Comparisons of the geoelectric units with the depositional sequences interpreted from the available seismic data outwith, but close to, Mersin Harbour reveal that the geoelectric unit GU3 corresponds to the depositional sequences C (mainly Holocene) and B (mainly Plio-Pleistocene). The geoelectric unit GU2 partly correlates with the depositional sequence B which appears to be Plio-Pleistocene in age. The geoelectric unit GU1, which has not been encountered in previous seismic surveys, is a new discovery within Mersin Harbour. Limited correlation between the seismic and resistivity structures in the study area is attributed to differences in the acoustic impedance and resistivity contrasts of sub-bottom layers, as well as the penetration versus resolution performance of the systems.  相似文献   
93.
Zonguldak coal basin is the only productive hard coal basin of Turkey. The eastern part of the basin is called as Bartin–Amasra District, which has deeper coal seams. The depth and difficulty of mining these coal seams make this district an important candidate for coalbed methane (CBM) recovery. However, there is not enough reservoir data for modeling purposes. In this study, the lithologic information collected for coal mining industry was used to determine the correlations and the continuity of the coal seams. The lithologic information was examined and the depths of the coal seams and the locations of the exploration boreholes were used to perform a reliable correlation using a new method. As a result of the correlation study, 63 continuous coal layers were found. A statistical reserve estimation of each coal layer for methane was made by using Monte Carlo simulation method. The initial methane in place found in the coal layers both in free and adsorbed states were estimated using probabilistic simulations resulted in possible reserve (P10) of 2.07 billion m3, probable reserve (P50) of 1.35 billion m3 and proven reserves (P90) of 0.86 billion m3.Among the determined continuous coal layers, coal layer #26 was selected for a preliminary investigation of the applicability of enhanced coalbed methane (ECBM) recovery and CO2 storage. The scarcity of coal seam reservoir data required a sensitivity study for the effects of reservoir parameters on operational performance indicators. The effects of adsorption, coal density, permeability, cleat porosity and permeability anisotropy parameters were examined using the Computer Modeling Group's (CMG) GEM module.  相似文献   
94.
Utilizing remote sensing (RS) and geographic information systems (GIS) tools, mineral composite characteristics (ferrous minerals (FM), iron oxide (IO), and clay minerals (CM)) of the Kelkit River Basin (15913.07 km2) in Turkey were investigated and mapped. Mineral composite (MC) index maps were produced from three LANDSAT-ETM+ satellite images taken in 2000. Resulting MC index maps were summarized in nine classes by using ‘natural breaks’ classification method in GIS. Employing bi-variety correlation analysis, relationships among index maps were investigated. According to the results, FM and IO index maps showed positive correlation, while CM index map is negatively correlated with FM and IO index maps. Negative correlations between iron and clay variables suggested that the dominant clay minerals of the study area might be smectite, illite, kaolinite, and chlorite, which have little or no iron content. Using field data for which their geographic coordinates had been determined by global positioning system (GPS), developed MC maps were verified, and found dependable for environmental and ecological modeling studies.  相似文献   
95.
The Haymana basin in central Anatolia (Turkey) formed on a Late Cretaceous to Middle Eocene fore-arc accretionary wedge. A sequential model is proposed for the 1-km-thick Lutetian Yamak turbidite complex (YTC) which is the youngest paleotectonic unit of the basin. The YTC represents a prograding submarine fan subdivided into three depositional sequences (DS), each several hundred meters thick. Each depositional sequence consists of a turbidite system (TS), with sandstone and conglomeratic sandstone beds alternating with mudstones, overlain by basin plain mudstones. In each turbidite system, the sandstone and mudstone sequential organization allows the distinction of smaller subdivisions, namely, basic sequences (BS) and basic units (BU), with each basic sequence being composed of several basic units. This subdivision, associated with a two-dimensional geometric reconstruction of the YTC, leads to a better understanding of the evolution in time and space of the submarine fan system. Lower to middle fan depositional lobes, and upper fan and slope channels, are represented. As a whole, the YTC progressed from a sand-poor to a sand-rich system. Depositional sequences (DS) of the YTC may correspond to third-order sea-level cycles of tectonic origin. Accordingly, fourth- and fifth-order cycles might be proposed for the BS and BU, respectively. However, partly because of the limited extent of exposures, the allocyclic origin of these finer subdivisions remains problematic.  相似文献   
96.
Summary The lunar tide in theE-layer of the ionosphere above Istanbul has been determined by the analysis of thefo E parameter from 1964–1967. Semi-diurnal variations were found to be significant. The seasonal and monthly variations of the amplitude and phase of the lunar tide show very little differences.  相似文献   
97.
. Turkey, located in the Alpine–Himalayan Orogenic Belt, is of great interest because of its abundant geothermal resources. In particular, the Ömer–Gecek region of Afyon is one of the important geothermal fields in Turkey exhibiting high geothermal potential. The stratigraphic sequence, from bottom to top, comprises schist and marbles called 'Afyon metamorphics', Neogene sediments, and trachyte and trachyandesites, which are the products of Afyon trachytic volcanism, and Karakaya basalts. The basalt flows form the latest phase of the volcanic activities. The magma pockets forming the volcanic rocks are the source of heat for the geothermal system. Aquifer rocks forming Pasadagi marbles are aged Palaeozoic. Despite the high geothermal potential, Afyon is one of the provinces in Turkey suffering from air pollution. In order to utilize this potential and reduce air pollution problems, Afyon Geothermal Heating System (AFJET) was initiated in 1994 and put into operation in 1996 with an installed capacity of 10,000 residences out of which 4,453 have been successfully heated. If Tunçbilek–Kütahya coal, which contains 17.56% ash and 1.27% combustible sulphur was burnt instead of utilizing geothermal energy, approximately 768 tons of SOx,78,740 t of CO2 and 4,083 t of particulate matter would have been emitted to the atmosphere. The results obtained from Afyon experience reveal that not only the emission of tremendous amounts of pollutants is eliminated, but also a cheap energy alternative with an environmental friendly heating source is provided.  相似文献   
98.
Albite deposits of western Turkey occur within gneiss in the basal part of the Menderes Metamorphic Massif. The most important deposits are located along the Karadere mineralization zone, within an anticlinorium of 15-km length with a direction of N10–30E. Detailed study of the four deposits forming the northern part of this zone has allowed us to discover large reserves of 100.65 million tons, of which 78% is composed of high-grade ore with a content of 10.27% Na2O. The remainder is formed by low-grade ore with 8.37% Na2O and 1.11% K2O and mixed ore with 4.61% Na2O and 4.05% K2O, with reserves of 14.4 and 8.2 million tons, respectively. To cite this article: U. Çak?r, C. R. Geoscience 337 (2005).  相似文献   
99.
100.
The study area is situated in a large agricultural field which produces tobacco, maize, and other yearly cultivated vegetables in Tekkeköy, Samsun (NE-Turkey). In addition, a significant part of this area to the north along the Black Sea coast is occupied by several industrial plants such as a copper smelting plant (KB?), a fertilizer plant (Tügsa?) and industrial park facilities (IPF). In order to reveal their environmental impacts, heavy metal analyses were conducted on soil, plant leaves and water samples collected within an area of approximately 30 km2 around these plants. Soil samples within an area of 10 km2 around these facilities are found to be highly polluted with Cu, Zn, Pb, Fe and Mn. Pollution occurs at surface and sharply dies out at 20 cm downwards in soil profile. Since the region is polluted mostly with base metals, the copper smelting factory appears to be the main source of pollution as it processes the massive sulfidic ores of the Black Sea area. Plants show Cu, Pb, Zn and Fe pollution around KB? and Tügsa? and Cu and Pb around IPF. Pollutants observed in tobacco (Nicotiana tobacum) are Cu, Pb, Zn, Fe and S; in maize (Zea mays) Cu, Zn and Fe; and in cabbage (Brassica oleracea) Cu, Pb, Fe and S. The analyses of water samples collected from the study area reveal that Pb and, to a lesser degree, Cu and Fe pollution stem from KB?; Cu, Fe and Mn pollution from Tügsa?; Pb and minor amounts of Fe and Mn pollution from IPF. Factor analyses from analyzed metals and anionic complexes in water show three distinct groups: (a) an association of heavy metals with Na, K and Mg referring to pollution and acid leaching of soil, (b) an association of NH4, Fe, SO4, Cl and Br indicating agricultural pollution and sea-water invasion in land near the shore line, and (c) HCO3 behaving in a different manner in heavy metal precipitation.  相似文献   
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