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1.
FEASIBLE STUDY ON THE INTEGRATION SYSTEM FOR THE SPACE MONITORING OF MAJOR EARTHQUAKES AND VOLCANOES IN TERRESTRIAL LAND 总被引:1,自引:1,他引:0
BOLi-qun 《中国地理科学(英文版)》2002,12(4):350-353
With the rapid development of space technology, earth observation technology and sky observatory technolo-gy, they have played a more and more important part in monitoring and predicting of earthquakes and volcanoes in the terres-trial land. In recent years, the related agencies have done the experiments and researches on monitoring and predicting ofearthquakes and volcanoes in the forewarning period by means of many approaches, such as satellite thermal infrared re-mote sensing (TIRS), Global Positioning System (GPS), differential interferometric synthesis aperture radar (D-INSAR),astronomical time-latitude residual anomaly, and Geographic Information Systems (GIS), etc. A quite large number of re-search foundation has been built in the fundamental theories and application methods. The experiments and researcheshave shown that these technology is efficient methods for high frequency crust movement. If the existed separate scientificforces and results are possibly assembled together to form a more complete integration monitoring system with the combina-tion of space, sky observation, ground, deep geology and macro anomaly, it will come into a new stage of monitoring andpredicting of earthquakes and volcanic eruptions. 相似文献
2.
1StrongtideandastronomicalconditionsPartial solar eclipse occurred 4 times in 1964, 1982 and 2000 respectively. Time interval is about 3 Saros periods (one Saros period is 18 years and 10.33~11.33 days). Total lunar eclipse occurred 2 times in 1964 and 2000 respectively and 3 times in 1982. However, there was no lunar eclipse in 1966, 1984 and 2002. It seems that they had similar astro-nomical conditions and the best was in 1982. The studies about the effect of tide on the global climate… 相似文献
3.
S. Miko G. Koch S. Mesić M. Šparica-Miko M. Šparica R. Čepelak A. Bačani P. Vreča T. Dolenec S. Bergant 《Environmental Geology》2008,55(3):517-537
Due to their balneotherapeutic features, the organic-rich sediments in Makirina Cove are an important source of healing mud.
An environmental geochemistry approach using normalization techniques was applied to evaluate the anthropogenic contribution
of trace metals to sediments used as healing mud. Sediment geochemistry was found to be associated with land-use change and
storm events, as well as with proximity of a road with heavy traffic in the summer months. Local valley topography preferentially
channels lithogenic and pollutant transport to the cove. Concentrations and distribution of trace metals indicate lithogenic
(Ni, Cr, Co) and anthropogenic (Pb, Cu, Zn and Se) contributions to the sediments. The calculation of enrichment factors indicates
a moderate (EFs between 2–3.5) input of anthropogenic Cu and Pb in surficial sediments to a depth of 10 cm. Patients using
the Makirina Cove sediments as healing mud could be to some extent exposed to enhanced uptake of metals from anthropogenic
sources via dermal contact. 相似文献
4.
This study presents a laboratory study of the following two aspects: (1) the influence of sea laver treatment acid on the
geoenvironmental properties of Ariake Sea tidal mud, and (2) the natural remediation effect on the sea laver treatment acid
contaminated Ariake Sea tidal mud caused by the upward seepage of pore water liquid in the mud. Firstly, the mechanisms of
the transport of sea laver treatment acid in the Ariake Sea tidal mud and the generation mechanisms of the upward seepage
flow in the Ariake Sea tidal mud are discussed. Secondly, a series of one-dimensional laboratory infiltration tests were carried
out to investigate the deterioration of the Ariake Sea tidal mud caused by the sea laver acid treatment practice. Test results
reveal that the acid treatment practice caused considerable change in the geochemical properties of the mud in terms of increase
in sulfide content and decrease in pH value. After the treatment by the sea laver treatment acid, the sulfide content of the
mud even exceeded the safe limit value for the benthos, which represents undesirable living condition for benthos. Thirdly,
series of laboratory fresh seawater infiltration tests for the deteriorated Iida site mud were conducted to illustrate this
natural remediation efficiency. It is found that with the infiltration of the fresh seawater, the sulfide content of the Iida
site mud was considerably reduced and pH value increased to an acceptable range for benthos living in the tidal flat mud.
With the increase in the infiltration time and the hydraulic gradient, the remediation efficiency could be increased. 相似文献
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7.
火山玻璃风化层的透射电镜研究 总被引:2,自引:0,他引:2
利用透射电镜(TEM)和X射线能谱(EDX)研究了长白山天池火山1000年和4000年前两次大喷发产生的火山玻璃风化层特征.TEM分析显示,4000年前大喷发浮岩中的火山玻璃风化层平均厚度3.7 mm,1000年前大喷发浮岩中的火山玻璃风化层平均厚度为1.0 mm.EDX分析显示,两次大喷发浮岩中的火山玻璃风化层化学组成与火山玻璃相比富Al、Fe,而si减少.火山玻璃风化层富Al发生在Al的浓度较高的中到弱酸溶液中(pH=5~6),火山玻璃表面形成含有少量的非晶质的Al、Si、Fe物质,这些非品质的次生物质是火山玻璃风化早期阶段形成的.天池火山喷发物中火山玻璃的微观特征的差异可能与火山喷发年代和喷发后的环境有关,研究天池火山不同期次喷发物中火山玻璃的微观特征具有一定的理论和实际应用价值. 相似文献
8.
Geophysical evidence of mud diapirism on the Mediterranean Ridge accretionary complex 总被引:2,自引:0,他引:2
A. Camerlenghi M. B. Cita B. Della Vedova N. Fusi L. Mirabile G. Pellis 《Marine Geophysical Researches》1995,17(2):115-141
Mud volcanoes, mud cones, and mud ridges have been identified on the inner portion of the crestal area, and possibly on the inner escarpment, of the Mediterranean Ridge accretionary complex. Four areas containing one or more mud diapirs have been investigated through bathymetric profiling, single channel seismic reflection profiling, heat flow measurements, and coring. A sequence of events is identified in the evolution of the mud diapirs: initially the expulsion on the seafloor of gasrich mud produces a seafloor depression outlined in the seismic record by downward dip of the host sediment reflectors towards the mud conduit; subsequent eruptions of fluid mud may create a flat topped mud volcano with step-like profile; finally, the intrusion of viscous mud produces a mud cone.The origin of the diapirs is deep within the Mediterranean Ridge. Although a minimum depth of about 400 m below the seafloor has been computed from the hydrostatic balance between the diapiric sediments and the host sediments, a maximum depth, suggested by geometric considerations, ranges between 5.3 and 7 km. The presence of thermogenic gas in the diapiric sediments suggests a better constrained origin depth of at least 2.2 km.The heat flow measured within the Olimpi mud diapir field and along a transect orthogonal to the diapiric field is low, ranging between 16 ± 5 and 41 ± 6 mW m–2. Due to the presence of gas, the thermal conductivity of the diapiric sediments is lower than that of the host hemipelagic oozes (0.6–0.9 and 1.0–1.15 W m–1 K–1 respectively).We consider the distribution of mud diapirs to be controlled by the presence of tectonic features such as reverse faults or thrusts (inner escarpment) that develop where the thickness of the Late Miocene evaporites appears to be minimum. An upward migration through time of the position of the décollement within the stratigraphic column from the Upper Oligocene (diapiric sediments) to the Upper Miocene (present position) is identified. 相似文献
9.
10.
Observations of fluid mud were made in the lower North Passage of the Yangtze Estuary in February 2000, on 10 -11 August 2000, on 30 - 31 August 2000 (after two strong typhoons), on 21 - 24 August 2000 (neap tide) and on 3 -6 September 2000 (mean tide) respectively. In situ data show that the fluid mud in this area consists of fine cohesive sediment (median size 7.23 μm). The formation and movement of fluid mud varied during the neap-spring and flood-ebb tidal cycle. Observations suggest that fluid mud phenomena in this area may be categorised in a three-fold manner as slack water, storm and saltwedge features. The thickness of the fluid mud layer of slack water during the neap tide ranged from 0.2 to 0.96 m, whereas during the mean tide, the thickness ranged from 0.17 to 0.73 m, and the thickness of the fluid mud layer was larger during slack water than at the flood peak. Shoals cover an area of 800 km^2 with a water depth smaller than 5 m. Erosion of these extensive intertidal mudflats due to storm action provides an abundant sediment source. This is particularly significant in this estuary when the tidal level is lower than 5 m. The lower North Passage is a typical zone of saltwater wedging, so the saltwedge fluid mud has the most extensive spatial range in the estuary. 相似文献