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191.
Application of the Engineering-Geological Conditions in Land-Use Plans in the Petrvald Region(Czech Republic) 总被引:3,自引:0,他引:3
Marian MARSCHALKO I??k YILMAZ Martin BEDNARIK Karel KUBE?KA Tomá? BOUCHAL 《《地质学报》英文版》2013,87(1):272-285
The objective of this paper is to demonstrate necessity to inform relevant parties about engineering-geological conditions for various practical purposes,especially including appropriate land-use planning.However,the relationship between relevant geological information and the geological environment is vital for foundation engineering purposes,especially where demanding structures are involved.This information is most conveniently structured when accumulated information concerning engineering-geological zones is utilized.This necessarily includes knowledge of rock workability and also of the pre-Quaternary bedrock,and these characteristics were then related to the current built-up area and future development according to the land-use plans in a case study are from the Petrvald Region(Czech Republic).The geological environment of area has been severely influenced by anthropogenic effects of deep black coal mining.Results of this research showed that future development should be founded on spoil banks,dumps,and settling basins. According to the land-use plan,this zone occupies 44.9%of the area of interest,and its materials predominantly emanate from mining in the Ostrava-Karvina Coal District.For future foundation structures planned there,it is imperative to consult detailed engineering-geological study.However, attention to and reliance on this necessity is not reflected in the existing land-use plan. 相似文献
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Xabier PEREDA-SUBERBIOLA Fabien KNOLL José Ignacio RUIZ-OME?ACA Julio COMPANY Fidel TORCIDA FERNáNDEZ-BALDOR 《《地质学报》英文版》2012,86(6):1389-1401
Prejanopterus curvirostra, from the Early Cretaceous of La Rioja province, was the first pterosaur genus and species described from Spain. The material comprises disarticulated cranial and postcranial remains from several individuals. The fossil-bearing bed is assigned to the lacustrine Leza Formation (eastern Cameros Basin, NW margin of the Iberian Range). This unit is regarded as either Berriasian-Valanginian or Barremian-Aptian. Prejanopterus curvirostris (specific name emended) was originally diagnosed on the basis of several characters of which the most significant was a lateral curvature of the rostrum. Re-examination of the holotype (rostrum) and paratype (partial rostrum with teeth) indicates that there is no genuine sideways bend of the preserved premaxilla-maxilla segments, but a slight dorsal curvature. Prejanopterus is characterized by a unique combination of characters: an emended diagnosis is provided. In contrast with previous estimates, the wing span of Prejanopterus was probably not much (if ever) in excess of 2 m. A phylogenetic analysis suggests that Prejanopterus is a basal pterodactyloid positioned between Pterodactylus and Cycnorhamphus-Gallodactylus. Prejanopterus represents the first evidence of Pterodactylidae in the Early Cretaceous of the Iberian Peninsula. 相似文献
194.
Aleksra ?AJNOVI? Vladimir SIMI? Branimir JOVAN?I?EVI? Olga CVETKOVI? Radovan DIMITRIJEVI? Nenad GRUBIN 《《地质学报》英文版》2008,82(6):1201-1212
Sediments of the western part of the Valjevo-Mionica basin (Serbia) were examined both geochemically and mineralogically to explain, on the basis of their sedimentologicai characteristics, the causes of changes in their qualitative and quantitative composition. A total of 62 samples obtained from the drillhole at depths up to 400 m was investigated. Using correlation of the obtained data, six geochemical zones were defined, two of which being specially distinguished by their mineralogical, geochemical and sedimentological characteristics. The first one, upper zone A, consists of banded marlstones interbedded with clay and oil shales and is characterized by presence of analcite and searlesite. These minerals and very high contents of Na20 indicate sedimentation in alkaline conditions with increased salinity in arid climate. That provided pronounced water stratification, as well as higher bioproductivity in the basin and sedimentary organic matter preservation. Therefore, the zone A sediments are characterized by high organic matter contents of the type which provides good potential for production of liquid hydrocarbons. Another specific zone, zone F, contains sediments with very high MgO, K2O and Li concentrations. Their geochemical correlation, as well as almost complete absence of illite in this zone, indicates the presence of interstratified clay mineral type illite-saponite (lithium-bearing Mg-smectite). 相似文献
195.
Aram BAYET-GOLL Paul M. MYROW Guillermo F. ACE?OLAZA Reza MOUSSAVI-HARAMI Asadollah MAHBOUBI 《《地质学报》英文版》2016,90(5):1572-1597
The Lower Ordovician Shirgesht Formation in central Iran is composed of siliciclastic and carbonate rocks deposited in diverse coastal and marine shelfal environments (tidal flat, lagoon, shoreface, offshore-shelf and carbonate ramp). Five facies associations contain diverse ichnofossil assemblages that show distinct proximal to distal trends formed in a wide range of physical-chemical conditions. The ethological groups of trace fossils in the Shirgesht Formation reflect a gradient of depositional stress conditions across a wave-influenced shoreline and shelf. Deposits of wave-influenced environments make up a significant component of the geological record of shallow marine settings, and the ability to determine paleoenvironments in detail in such successions is critical for reconstruction of depositional histories and sequence-stratigraphic interpretation.The Cruziana ichnofacies of the study shows highly diverse suites that record the establishment of a benthic community under stable conditions and a long-term colonization window. The Skolithos ichnofacies recognized is a low diversity opportunistic ichnocommunity suite that resulted from colonization after tempestite deposition in a stressed environment. The strata record an onshore to offshore replacement of the Cruziana ichnofacies (with abundant feeding traces of deposit-feeders) by the Skolithos ichnofacies (dominated by suspension-feeders and predators). A transitional zone between the two ichnofacies coincides with the offshore-transition/distal lower-surface deposits. The distribution of ichnofacies, the diversity and range of ethological characteristics reflected by the ichnogenera, and the wide range of wave-dominated coastal facies demonstrate the potential to use individual trace fossils and ichnofacies for significantly refined palaeoenvironmental analysis of wave-dominated coastal settings, particularly in Ordovician successions. 相似文献
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Janja Kogov?ek 《《地质学报》英文版》2010,84(1):206-212
Three tracing tests from the same injection point executed at low, medium, and high water levels in the karst aquifer near Tianshengan village, Lunan Stone Forest, Yunnan Province, China, have revealed the basic properties of underground water flow. They showed the general directions of water flows; tracer concentrations were observed at six successive points allowing for the calculation of apparent dominant flow velocities at these sections towards the Dalongtan karst spring. For the high water level, the discharge between single sections was between two and 10 times greater than that at low water level. For the medium water level, the flow velocity at different sections was between 1.4 and 3.7 times faster than that at low water level; and for high water level, it was between 1.3 and 2.7 times faster than that at medium water level. The fastest water flow appeared at the first section (23 cm/s at medium water level); and the slowest (0.6 cm/s at low water level) appeared where water flow must cross the Tianshengan fault (north–south direction), and later, a layer of 20–30 m thickness of quartz sandstone and shale clay-stones. It was also possible to calculate the recovery of the tracer for point 4, Dakenyan, where discharge was measured. At the medium water level, 50% of the injected tracer was detected a half-day after its first appearance and at low water level after more than 3 days. The previously published research illustrates the transport velocities of possible contaminants and their solubilities in water at different hydrological conditions. 相似文献
199.
Cockroach as the Earliest Eusocial Animal 总被引:2,自引:1,他引:1
Peter VR?ANSKY 《《地质学报》英文版》2010,84(4):793-808
<正>A completely preserved cockroach Sociala perlucida gen.et sp.nov.(Blattida:Socialidae fam.nov.)is described from the Mesozoic(Albian Early Cretaceous)amber of Archingeay in France.It is categorized within the new family Socialidae,originating from the Mesozoic cockroach family Liberiblattinidae,and representing the sister group to the most basal known eutermite families.Numerous direct and indirect morphological evidence(such as a unique narrow body and pronotum with reduced coloration,legs without carination and with numerous sensillar pitts(forelegs)as adaptations to life in nests analogical to the living termitophillous species; enlarged head,long palps for communication,a general venation modified in a direction towards termites (subcosta and radial vein[R]approximated,R branches approximated,simplified,cross-veins reduced),and possibly also the development of the breaking forewing sutura for detaching wings after marriage flight),suggest its eusocial mode of life.Thus,the first eusociality originated within cockroaches,prior to giving birth to termites; termites and Cryptocercus are not directly related.The group of eusocial cockroaches makes termite morphotaxon polyphyletic,but also in this case,the erection of a new order for mastotermites(including Cratomastotermitidae)and/or the inclusion of eusocial,morphological cockroaches within termites appears counterproductive,thus an example of such a general exception to the taxonomical procedure is provided. 相似文献
200.