全文获取类型
收费全文 | 9245篇 |
免费 | 1700篇 |
国内免费 | 2191篇 |
专业分类
测绘学 | 456篇 |
大气科学 | 261篇 |
地球物理 | 780篇 |
地质学 | 9488篇 |
海洋学 | 1060篇 |
天文学 | 18篇 |
综合类 | 554篇 |
自然地理 | 519篇 |
出版年
2024年 | 86篇 |
2023年 | 301篇 |
2022年 | 393篇 |
2021年 | 393篇 |
2020年 | 282篇 |
2019年 | 348篇 |
2018年 | 247篇 |
2017年 | 246篇 |
2016年 | 278篇 |
2015年 | 361篇 |
2014年 | 533篇 |
2013年 | 400篇 |
2012年 | 499篇 |
2011年 | 494篇 |
2010年 | 453篇 |
2009年 | 475篇 |
2008年 | 522篇 |
2007年 | 478篇 |
2006年 | 492篇 |
2005年 | 407篇 |
2004年 | 448篇 |
2003年 | 553篇 |
2002年 | 541篇 |
2001年 | 542篇 |
2000年 | 491篇 |
1999年 | 399篇 |
1998年 | 420篇 |
1997年 | 444篇 |
1996年 | 333篇 |
1995年 | 314篇 |
1994年 | 250篇 |
1993年 | 159篇 |
1992年 | 126篇 |
1991年 | 106篇 |
1990年 | 136篇 |
1989年 | 105篇 |
1988年 | 24篇 |
1987年 | 12篇 |
1986年 | 7篇 |
1985年 | 7篇 |
1984年 | 7篇 |
1983年 | 5篇 |
1959年 | 1篇 |
1958年 | 1篇 |
1951年 | 1篇 |
1950年 | 1篇 |
1946年 | 1篇 |
1945年 | 2篇 |
1943年 | 2篇 |
1934年 | 3篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
111.
龙胜祥 《中国地质大学学报(英文版)》2008,19(6):665-674
This article reports the main formation models and distribution of the oil and gas pools in Tarim basin,China,including (I) occurrence of the found oil and gas pools,(2) main formation models of oil and gas pools,and (3) distribution law of oil/gas pools.Petroleum is distributed widely in the strata of Tarim basin from the Sinian at the bottom to the Neogene at the top.However,the found oil and gas fields are mainly distributed in Shaya (沙雅) uplift,Tazhong (塔中) uplift,and Kuche (库车)depression.This article presents 4 main formation models,namely,early formation and long-term preservation,early formation and late reformation,middle-late multiphase-multisource formation,late single-stage formation.Tarim basin is very rich in petroleum resources.Long-term inherited intrabasinal paleohighs and slope zones are the most favorable areas for accumulation of hydrocarbons,but the types of oil and gas pools are different from area to area.The control of unconformities and faults on hydrocarbon accumulating is prominent in Tarim basin.Preservation conditions are of utmost importance.Formation of some oil and gas pools is the result of reforming and re-accumulating of early accumulated hydrocarbons. 相似文献
112.
据苏皖南部地区地表露头及部分井下所发现的海相油气显示表明,这里存在海相油气资源勘探远景,关注这一地区的海相油气资源,如何开展和寻找这类油气资源,将有利于该地区区域性经济建设的可持续发展。 相似文献
113.
114.
115.
116.
117.
基于传统吸附烃概念的烃类检测新技术 总被引:5,自引:1,他引:4
烃类是地表油气地球化学勘查地下油气藏的直接指标.目前我国油气化探中常用的酸解烃法检测出的烃类,不应定义为"吸附烃",它是介质吸收的产物,属结合态烃类,应定义为"吸收烃".地表酸解烃异常十分稳定,重现性好,能够很好地证明地质历史上曾经有过的烃类运移过程,但在反映目前深部油气信息方面具有多解性.针对酸解烃法的弱点,依据烃类垂向运移理论和物质吸附作用原理,自行设计开发、研制了一套吸附烃脱气装置,建立了土壤吸附烃提取新技术和检测方法.该方法有利于在近地表获取油气系统的动态信息,强化烃类测量法对其信息源的探测,可以提高地表油气化探预测油气分布的成功率. 相似文献
118.
119.
Research Advances and Exploration Significance of Large-area Accumulation of Low and Medium Abundance Lithologic Reservoirs 总被引:1,自引:1,他引:0
In recent years, a series of large low and medium abundance oil and gas fields are discovered through exploration activities onshore China, which are commonly characterized by low porosity-permeability reservoirs, low oil/gas column height, multiple thin hydrocarbon layers, and distribution in overlapping and connection, and so on. The advantageous conditions for large-area accumulation of low-medium abundance hydrocarbon reservoirs include: (1) large (fan) delta sandbodies are developed in the hinterland of large flow-uncontrolled lake basins and they are alternated with source rocks extensively in a structure like "sandwiches"; (2) effective hydrocarbon source kitchens are extensively distributed, offering maximum contact chances with various sandbodies and hydrocarbon source rocks; (3) oil and gas columns are low in height, hydrocarbon layers are mainly of normal-low pressure, and requirements for seal rock are low; (4) reservoirs have strong inheterogeneity and gas reservoirs are badly connected; (5) the hydrocarbon desorption and expulsion under uplifting and unloading environments cause widely distributed hydrocarbon source rocks of coal measures to form large-area reservoirs; (6) deep basin areas and synclinal areas possess reservoir-forming dynamics. The areas with great exploration potential include the Paleozoic and Mesozoic in the Ordos Basin, the Xujiahe Formation in Dachuanzhong in the Sichuan basin, deep basin areas in the Songliao basin etc. The core techniques of improving exploration efficiency consist of the sweetspot prediction technique that focuses on fine characterization of reservoirs, the hydrocarbon layer protecting and high-speed drilling technique, and the rework technique for enhancing productivity. 相似文献
120.