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941.
942.
《科学通报(英文版)》2004,49(Z1):60-60
Lunnan heave had experienced denudation during late Caledonian and Hercynian movements and reconstruction during Indosinian movement. Lunnan heave and its circumference areas are located on the direction of petroleum migration, and experienced three reservoir formation cycles that are divided by wave cycle: The first reservoir formation cycle is characterized by breakage, the second by alteration, and the third by enrichment. Three layers of dissolving-cave developed on the vertical in Lunnan area. Development degree of slit-cave system and their connectivity are important factors to control petroleum enrichment in the weathering crust reservoir. The area where dissolving-caves are communicated by silts and faults was a fine petroleum enrichment area, and water was often encountered in the area with isolation cave while drilling because of no oil and gas origin. The top part of the faulted-horst as a leaking area is bearing water area, and the higher part of slope nearing the top part of the faulted-horst as a high seepage area is a heavy oil area due to lack of fine caprock, and the lower part of slope and the platform are light and condensate oil area. The area with the middle-upper Ordovi-cian is the favorable area to explore original carbonate reservoir formed in the earlier stage. The best favorable petroleum enrichment area for carbonates is surrounding Lunnan heave along the slope down to the direction of sags. The precondition to discover petroleum in carbonates is accurately prognosticating the distribution area of silts and caves, and the key to improving the exploration success ratio is accurately recognizing silts and small faults. 相似文献
943.
944.
为还原沁水盆地中东部热演化史,以某页岩气井山西组及太原组26件海陆过渡相泥页岩实测数据为基础,利用Petro Mod软件进行了热演化史模拟,依据模拟结果对油气生成及成藏进行了分析,结果表明:研究区内烃源岩干酪根类型以Ⅲ型为主,有机质演化成熟度高,具有良好的生烃潜力;热演化史与构造演化史存在耦合作用,受印支运动及燕山运动影响,地层温度经历了缓慢上升-缓慢冷却-异常高温-快速冷却四个阶段;太原组及山西组烃源岩有机质演化过程中镜质组反射率(Ro)值发生一次跃变,最终演化至2. 0%左右,于早白垩世烃源岩发生二次生烃作用进入产气阶段,加之上覆致密的盖层形成了良好的煤系气藏。 相似文献
945.
《Journal of Natural History》2012,46(2):289-293
Summary Streams and meander lakes in the Mato Grosso, between the Rio das Mortes and the Rio Suiá Missú, have low conductivities ranging from 12 to 50 μmho/cm/20°c, but exceptional isolated pools reach 800 μmho under the influence of evaporation. Rainfall at the beginning of the wet season had conductivities up to 110 μmho, but the general level of conductivity fell as the wet season progressed. Run-off water flowing over the ground during heavy rain generally had a higher conductivity than the rain. Short-term fluctuations in the conductivity of small streams showed increases with heavy rain accompanied by surface run-off. The rainfall had a high calcium to sodium ratio. It is estimated that during the period from 1 September to 30 November 1968 the rainfall supplied the area with at least 4 kg Ca per hectare. 相似文献
946.
《Journal of Natural History》2012,46(37-38):2373-2384
This paper expands the known geographic distribution of Corvospongilla seckti Bonetto and Ezcurra de Drago, 1966 to another two Brazilian hydrographic basins, the East Atlantic and São Francisco basins. Simultaneously, it reassesses the status of C. seckti and Corvospongilla volkmeri De Rosa Barbosa, 1988. Re-examination of the holotype of C. volkmeri revealed no remarkable diagnostic features to differentiate it from C. seckti, given our present knowledge on the variability of the latter. Accordingly, C. volkmeri is considered a junior synonym of C. seckti. 相似文献
947.
《Journal of Natural History》2012,46(45-48):2789-2800
Sipunculans and echiurans collected by the “DIVA 1” expedition by RV Meteor (Cruise M48/1) to the deep‐sea bottom of the Angola Basin are recorded. Seven species from five genera and two separate phyla are recognized; only the echiuran Pseudoikedella achaeta has not been recorded hitherto in the southern sector of the Atlantic Ocean. A gradient analysis using redundancy analysis (RDA) under the CANOCO package indicates the existence of a neat latitudinal gradient of sipunculans along the Angola Basin from the southernmost stations towards the northern ones. The local abundance of abandoned horny tubes of polychaetes at some of the sampling sites of the northernmost stations explains the dense aggregations of Nephasoma diaphanes. This species exhibits an opportunistic lifestyle inside empty polychaete tubes on the abyssal plains of the Angola Basin. 相似文献
948.
鄂尔多斯盆地陕北斜坡带三叠系延长组和侏罗系油气成藏期研究 总被引:6,自引:1,他引:6
通过对鄂尔多斯盆地烃源岩的生烃史、构造运动特征、包裹体均一温度和伊利石K-Ar同位素定年的研究,结合研究区的裂缝发育特征,综合分析了三叠系延长组和侏罗系油气成藏期.鄂尔多斯盆地形成演化过程中经历了多期构造运动,其中影响最大的是早白垩世末期的构造运动.长7段泥质烃源岩在早白垩世初期开始大量生烃,对侏罗系延9段裂缝储层和三叠系延长组伊利石K-Ar同位素定年以及对储层流体包裹体均一温度分析显示,陕北斜坡带三叠系延长组油藏形成于早白垩世的早中期,而侏罗系延安组的油藏则形成于早白垩世末的构造抬升期,对应时间为晚白垩世早—中期. 相似文献
949.
评价川中—川西南地区中三叠统雷口坡组第三段暗色碳酸盐烃源岩的生烃能力,预测雷口坡组天然气新的勘探领域.在典型钻井岩心和岩屑样品的有机地球化学特征分析基础上,结合测井解释TOC技术,刻画出27口井的有效烃源岩厚度,并且应用有机质热模拟参数法对各井烃源岩的生气强度进行定量计算.研究表明:暗色碳酸盐烃源岩的残余有机碳质量分数... 相似文献
950.
柳江盆区地壳经过前地槽、地槽、地台和地洼四大不同历史发展阶段,但由于盘内仅发育有地台和地洼两大构造层,因而其成矿作用的大地构造类型只有地合型和地洼型两大类。前者有煤、铝土矿等外生矿产;后者既有外生煤矿,又有内生铅、锌、铜、铁等矿化特征。 相似文献