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991.
分形理论在成矿预测中的应用 总被引:15,自引:0,他引:15
分形理论是人类进行思维和探索复杂性而定量描述的一种新方法,是研究大自然界中不规则现象的有力数学工具,在地质领域中的应用非常广泛。介绍R/S分析法原则,并结合实例来研究地质体和地质现象的分形特征,确定地质异常,建立地质异常分形模型。 相似文献
992.
栗木矿田某些新方法找矿试验研究和找矿效果 总被引:1,自引:0,他引:1
在栗木矿田进行的土壤离子电导率、地电提取、吸附相态汞新方法试验研究表明,钨锡长石石英脉矿床上获得了高、低双峰电导率异常、单峰吸附相态汞异常和多点连续高峰地电提取多金属异常;钽铌花岗岩型矿床上获得锯齿状电导率异常、双峰夹一谷的“凹”形吸附相态汞异常和多点连续高峰地电提取多金属异常。表明在常规化探方法反映不出异常的厚层覆盖区,新方法能测出强度高、衬度大且与矿体位置吻合较好的异常。并对涧口—焦巴井找矿预测区三种新方法综合异常部位进行了工程验证,见到了矿体,说明各新方法找矿效果良好,方法可行。 相似文献
993.
The Junggar orogen, Xinjiang, China, is an important part of the Ural-Mongolian orogen.The collisional orogenesis in this region occurred primarily in the Carboniferous and Permianwith an evolutional process of early compression and late extension. Mineralization of gold andother metals in the Junggar orogen occurred mainly in the Permian and in a few cases in theLate Carboniferous. The deposits are largely distributed in areas where collisional orogenesiswas intensive and formed in a transitional stage from compression to extension. Therefore, goldmineralization in the Junggar orogen is fully consistent with the collisional orogenesis in time,space and geodynamic setting. This indicates that the mineral deposit model of collisionalorogenesis is applicable to prospecting and study of ore deposits in the Junggar orogen.Furthermore, the factual distribution of gold and other deposits in this region is just the same asthe collisional orogenic model presents. 相似文献
994.
Selenium Enrichment in Cambrian Stratabound Gold Deposits in the Western Qinling Mountains 总被引:1,自引:0,他引:1
Liu Jiajun Open Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang Guizhou Zheng Minghu Chengdu Institute of Technology Chengdu Sichuan Liu Jianming Research Centre of Mineral Resources Exploration Chinese Academy of Sciences Beijing Zhou Yufeng Gu Xuexiang Zhang Bin Lin Li Chengdu Institute of Technology Chengdu Sichuan Lu Wenquan Institute of Comprehensive Utilization of Mineral Resources Chengdu Sichuan 《《地质学报》英文版》1997,71(4):423-432
Stratabound gold deposits in the western Qinling Mountains occur in Cambrian chert formation composed of carbonaceous chert and carbonaceous slate. The distinctive chert formation provides important grounds for the mineralization and controls on the formation of gold deposits. Study shows that Se is exceptionally higher in both host rocks and gold orebodies. It may be recovered as a valuable component in ores for total utilization, and in some localities even independent Se orebodies (which are mined exclusively for Se) may be delineated. In gold ore Se mainly occurs as independent minerals or in the isomorphous form in sulphides and there is a positive correlation between Se and Au. 相似文献
995.
996.
997.
Wang Guanfu Chen Zhihong Ding Shiying Ren FugenTianjin Institute of Geology Mineral Resources Tianjin China 《《地质学报》英文版》1996,70(1):74-86
Based on palaeomagnetic studies of the Precambrian gold deposits in the Xiong'ershan area, Henan Province, the authors infer that the ore-forming processes of the Beiling alteration-type gold ore deposit and the Dianfang breccia-type gold ore deposit started in the Proterozoic, and was superimposed by later mineralization, whereas the mineralization age of the Jiguanshan quartz- vein type gold ore deposit is Yanshanian. 相似文献
998.
外生金包括砾岩金和松散砂金,是外能作用在地表开放条件下形成的。在地壳发展过程中,动力学成矿的时空演化是连续的,但主要集中在早、晚元古代及早、晚古生代和中生代,而大发展于新生代。依据演化规律和矿化环境,提出5个找矿有望的外生金成矿带。 相似文献
999.
扬子地台西南缘铜金铅锌银成矿预测研究 总被引:1,自引:0,他引:1
扬子地台西南缘位于滨西太平洋成矿域、特提斯成矿域和秦祁昆成矿域的结合部位,是中国最重要的成矿带之一,具广阔的找矿前景。本次采用系统论、信息论、控制论并结合区内的成矿系列和成矿特征,共预测出Ⅰ级成矿带6个,Ⅱ级成矿远景区带6个,Ⅲ级重点普查区12个。在此基础上,依据矿种急缺度、成矿条件有利度、预测依据充分度、预测矿床规模大小度、预测靶区可利用度、交通方便度、区位条件有利度以及经济和社会效益度8原则,且分别赋值进行半定量评价,从而优选出十佳找矿靶区并进行了排序。这些找矿靶区都转入普查,经过部分工程验证,得到了证实,开拓了科研找矿,理论找矿,与生产实际相结合的一条新路子。 相似文献
1000.
A recent early diagenetic banded iron-manganese mud has been forming underground in a closed lead-zinc mine for approximately 40 years. The processes leading to the banded structure of the precipitate were studied during a period of 2 years. Therefore, 19 physical and chemical parameters were measured regularly in short intervals. The resulting time series were analysed with respect to the data sets of the monthly chemical analyses of the descendent mine water, the daily rainfall and the mineral content. The results reveal that the precipitated material undergoes internal self-organization due to interaction of redox, colloid-chemical, microbial, electrical and ripening processes, and not exclusively produced by seasonal fluctuations of material input. Thus, the primary banding of the material, caused by externally forced fluctuations of the redox conditions within the mine water, is reorganized after a short time. The finally observed bands are controlled by non-linear coupling of reaction and transport processes within the mud. A genetic model for the banded mineralization was developed and verified by numerical simulation. 相似文献