全文获取类型
| 收费全文 | 178篇 |
| 免费 | 60篇 |
| 国内免费 | 76篇 |
专业分类
| 地球物理 | 9篇 |
| 地质学 | 288篇 |
| 海洋学 | 6篇 |
| 综合类 | 10篇 |
| 自然地理 | 1篇 |
出版年
| 2022年 | 5篇 |
| 2021年 | 5篇 |
| 2020年 | 7篇 |
| 2019年 | 11篇 |
| 2018年 | 11篇 |
| 2017年 | 4篇 |
| 2016年 | 10篇 |
| 2015年 | 11篇 |
| 2014年 | 12篇 |
| 2013年 | 14篇 |
| 2012年 | 17篇 |
| 2011年 | 24篇 |
| 2010年 | 11篇 |
| 2009年 | 14篇 |
| 2008年 | 15篇 |
| 2007年 | 24篇 |
| 2006年 | 16篇 |
| 2005年 | 12篇 |
| 2004年 | 14篇 |
| 2003年 | 7篇 |
| 2002年 | 7篇 |
| 2001年 | 6篇 |
| 2000年 | 11篇 |
| 1999年 | 10篇 |
| 1998年 | 7篇 |
| 1997年 | 6篇 |
| 1996年 | 11篇 |
| 1995年 | 2篇 |
| 1994年 | 5篇 |
| 1993年 | 4篇 |
| 1991年 | 1篇 |
排序方式： 共有314条查询结果，搜索用时 62 毫秒
1.
R. L. Dunstone 《Australian Journal of Earth Sciences》2019,66(1):57-70
Devonian fossil localities are summarised for coastal southeastern Australia, including both marine invertebrates representing a major late Frasnian (Late Devonian) transgression, and plant remains of Middle–Late Devonian age in associated non-marine strata. Lycopsid plant specimens (Leptophloeum) from near Majors Creek, NSW, first documented by Edgeworth David and E. F. Pittman in association with marine fossils to demonstrate a Late Devonian age, are illustrated for the first time. Lycopsid plants of presumed Middle Devonian age are illustrated from three new localities: Yowrie River inland from Cape Dromedary, Tuross River northwest of Narooma and Charlies Forest Road northeast of Braidwood. The Yowrie River occurrence (in float) indicates probable Middle Devonian strata upstream that are not shown on published maps. The Tuross River occurrence is in sheared and folded strata previously mapped as Ordovician, and the Braidwood occurrence demonstrates Devonian black shales adjacent to previously mapped Ordovician. Evidence supporting alternative thrust or simple fold interpretations for the Budawang Synclinorium is discussed, and relevant Ordovician fossil localities are listed. 相似文献
2.
塔里木盆地塔中-巴楚地区奥陶系内部存在一期重要的不整合。通过对数十口钻井的地层、古生物研究及与露头剖面的对比,发现该不整合的顶、底层位变化较大,地层缺失量在不同地区有所差异,可大致分为两种情况:其一是塔中地区,上奥陶统良里塔格组覆于鹰山组第三段(下奥陶统上部)之上,且有部分钻井良里塔格组下部也发育不全,缺失了至少11个牙形石带,相当于有17~20Ma的地层缺失;其二是巴楚地区,良里塔格组覆于鹰山组第二段或鹰山组第一段(中奥陶统下部)之上,缺失了至少8个牙形石带,相当于有约14Ma的地层缺失。上述地层缺失主要是由于中奥陶世以后塔里-巴楚地区出水成陆,碳酸盐岩地层受大气淡水溶蚀的结果。在不整合之下碳酸盐岩地层中形成的岩溶是十分重要的油气储层。因此,对该不整合的研究对于塔中、巴楚地区奥陶系,特别是鹰山组的油气勘探具有重要的意义。 相似文献
3.
Seismic and drilling well data were used to examine the occurrence of multiple stratigraphic unconformities in the Tarim Basin, NW China. The Early Cambrian, the Late Ordovician and the late Middle Devonian unconformities constitute three important tectonic sequence boundaries within the Palaeozoic succession. In the Tazhong, Tabei, Tadong uplifts and the southwestern Tarim palaeo‐uplift, unconformities obviously belong to superimposed unconformities. A superimposed unconformity is formed by superimposition of unconformities of multiple periods. Areas where superimposed unconformities develop are shown as composite belts of multiple tectonic unconformities, and as higher uplift areas of palaeo‐uplifts in palaeogeomorphologic units. The contact relationship of unconformities in the lower uplift areas is indicative of truncation‐overlap. A slope belt is located below the uplift areas, and the main and secondary unconformities are characterized by local onlap reflection on seismic profiles. The regional dynamics controlled the palaeotectonic setting of the Palaeozoic rocks in the Tarim Basin and the origin and evolution of the basin constrained deposition. From the Sinian to the Cambrian, the Tarim landmass and its surrounding areas belonged to an extensional tectonic setting. Since the Late Ordovician, the neighbouring north Kunlun Ocean and Altyn Ocean was transformed from a spreading ocean basin to a closed compressional setting. The maximum compression was attained in the Late Ordovician. The formation of a tectonic palaeogeomorphologic evolution succession from a cratonic margin aulacogen depression to a peripheral foreland basin in the Early Caledonian cycle controlled the deposition of platform, platform margin, and deep‐water basin. Tectonic uplift during the Late Ordovician resulted in a shallower basin which was followed by substantial erosion. Subsequently, a cratonic depression and peripheral or back‐arc foreland basin began their development in the Silurian to Early–Middle Devonian interval. In this period, the Tabei Uplift, the Northern Depression and the southern Tarim palaeo‐uplift showed obvious control on depositional systems, including onshore slope, shelf and deep‐water basin. The southern Tarim Plate was in a continuous continental compressional setting after collision, whereas the southern Tianshan Ocean began to close in the Early Ordovician and was completely closed by the Middle Devonian. At the same time, further compression from peripheral tectonic units in the eastern and southern parts of the Tarim Basin led to the expansion of palaeo‐uplift in the Late Devonian–Early Carboniferous interval, and the connection of the Tabei Uplift and Tadong Uplift, thus controlling onshore, fluvial delta, clastic coast, lagoon‐bay and shallow marine deposition. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
4.
5.
6.
雪峰山基底隆升带及其邻区印支期陆内构造特征与成因 总被引：7，自引：0，他引：7
狭义的华南陆块东部包括扬子地块和华夏地块,而雪峰山陆内构造系统是扬子地块的重要组成部分。通过对雪峰山地区印支期地层角度不整合时空分布规律的分析表明,高角度不整合—微角度不整合—平行不整合—整合的空间分布区域依次由东往西递变渐新。根据褶皱变形分析得出,雪峰山地区在印支期发育了北东东向和北北东向2个轴迹方向的褶皱,后期叠加了南北向弧形逆冲推覆构造。区域构造背景和动力学分析表明,扬子地块内部印支期总体北东向的变形形迹与东西轴向的秦岭—大别造山带和扬子地块南部东西轴向的构造线相垂直;其原因是:扬子地块与华夏地块最终陆内收缩变形的时间比扬子与华北沿秦岭—大别造山带的陆间碰撞拼合的时间早,印支早期的先存北北东向构造线在印支晚期由于扬子地块顺时针旋转变位为北东东向,从而决定了印支早期现今北东东向的构造线,随后的第二幕北北东向构造线的形成是在与早期第一幕变形的应力场相同的同一构造应力场作用下形成的。但是,秦岭—大别造山带近东西向的构造线取决于主动大陆边缘,即总体近东西向的华北陆块南缘边界,其原始方位为总体近东西向。这些复杂边界条件和旋转决定了先形成彼此近于垂直的构造线,然后拼接形成现今构造线垂直的格局。 相似文献
7.
冀中坳陷潜山油气输导体系及与油气藏类型的匹配关系 总被引：4，自引：0，他引：4
通过总结前人研究结果,利用测井、钻井地质和地化等资料,对冀中坳陷潜山油气藏类型和油气输导体系特征进行研究,并结合已发现的潜山油气藏,建立了不同油气输导体系与潜山油气藏类型的匹配关系。结果表明:根据不同的圈闭遮挡条件,可将冀中坳陷潜山油气藏分为潜山顶、潜山坡和潜山内幕油气藏等3种类型;潜山油气输导体系发育断裂、不整合、内幕溶蚀层和复合型输导体系等4种类型;受碳酸盐岩地层、断层活动性影响以及与油气生成时间的匹配,断裂型输导体系具有高效性和时效性的特征,有利于形成潜山顶和内幕油气藏;不整合型输导体系由不整合上部底砾岩和下部淋浴带组成,具有"双层"输导的特点,有利于形成潜山顶和潜山坡油气藏;内幕溶蚀层型输导体系由潜山内部的溶蚀孔-洞-缝系统组成,其发育程度受内部地层泥质含量控制,有利于形成潜山内幕油气藏;复合型输导体系由单一型输导体系复合形成,具有"多样式"的特点,可以形成潜山顶、潜山坡和潜山内幕油气藏。 相似文献
8.
袁丽 《地球科学与环境学报》2011,33(2):163-167
从几何学的观点出发,针对纯油藏和具有气顶的油气藏,采用单储系数、横截面面积与油层横向分布长度三者乘积的方式改进采用单储系数、含油面积与油层厚度三者乘积方式的传统容积法,提出相应的地层不整合遮挡油气藏地质储量计算新公式,并根据油气藏的特点提出水平井钻遇油气藏厚度的预测公式。地层不整合遮挡油气藏的地质储量计算目前主要采用容积法,这类方法不仅计算繁琐,而且不确定因素较多;改进后的新方法计算简单方便,理论性更强,存在的不确定因素显著减少。采用新方法在高青油田高424块高424-1井区进行了实践应用。实践表明:改进的新方法适用于地层不整合遮挡油气藏的地质储量计算及预测水平井钻遇油气藏厚度。 相似文献
9.
基于"构造体系控油作用研究"项目,总结中国东部中新生代大地构造的基本特征及其演变的内在规律。研究表明,中国东部中新生代构造形变史,以侏罗纪末幕运动为标志划分为前后2个大阶段,发育2种巨型扭动构造型式,即华夏系和新华夏系,其间存在广泛的构造不整合;显示二元结构,即新华夏系形变构造层与华夏系形变构造层的叠置,是本区大地构造的基本特征。 相似文献
10.
The Hala’alat Mountains are located at the transition between the West Junggar and the Junggar Basin.In this area,rocks are Carboniferous,with younger strata above them that have been identified through well data and high-resolution 3D seismic profiles.Among these strata,seven unconformities are observed and distributed at the bases of:the Permian Jiamuhe Formation,the Permian Fengcheng Formation,the Triassic Baikouquan Formation,the Jurassic Badaowan Formation,the Jurassic Xishanyao Formation,the Cretaceous Tugulu Group and the Paleogene.On the basis of balanced sections,these unconformities are determined to have been formed by erosion of uplifts or rotated fault blocks primarily during the Mesozoic and Cenozoic.In conjunction with the currently understood tectonic background of the surrounding areas,the following conclusions are proposed:the unconformities at the bases of the Permian Jiamuhe and Fengcheng formations are most likely related to the subduction and closure of the Junggar Ocean during the late Carboniferous-early Permian;the unconformities at the bases of the Triassic Baikouquan and Jurassic Badaowan formations are closely related to the late Permian-Triassic Durbut sinistral slip fault;the unconformities at the bases of the middle Jurassic Xishanyao Formation and Cretaceous Tugulu Group may be related to reactivation of the Durbut dextral slip fault in the late Jurassic-early Cretaceous,and the unconformity that gives rise to the widely observed absence of the upper Cretaceous in the northern Junggar Basin may be closely related to large scale uplift.All of these geological phenomena indicate that the West Junggar was not calm in the Mesozoic and Cenozoic and that it experienced at least four periods of tectonic movement. 相似文献