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The Fula Sub-basin of the Muglad Basin of southern Sudan is an active-fault bounded basin with an area of approximately 3300 km2. The Lower Cretaceous Abu Gabra Formation formed during the first of three rifting cycles. It can be subdivided into five 3rd-order sequences named SQA∼SQE from bottom to top, indicating five stages of tectonostratigraphy and tectonosedimentary evolution. The spatial distribution and temporal evolution of clastic depositional systems are described in this paper based on integrated analysis of seismic, core and well logging data. In the Abu Gabra Formation of the Fula Sub-basin, a variety of depositional systems are recognized, namely, fan delta, braided delta, delta, sublacustrine fan and lacustrine system. The Fula Sub-basin has undergone a complex and phased rifting evolution, and a high abundance of transfer zones developed, causing the resulting distribution and architecture of both the sequence and depositional system to be controlled by various types of transfer zones. The following three types of sequence architectures from northern to southern part of the Fula Sub-basin have been identified: simple dustpan-shaped sequence architecture in the north, transfer-zone sequence stratigraphic architecture in the middle and graben-shaped sequence architecture in the south. The sequence architecture is under the control of the large-scale central transfer zone, and nine models are built to study the effect of at least three categories of small-scale transfer zones on the depositional systems in the Fula Sub-basin. The small-scale transfer zones play significant roles in basin fill, primarily in controlling of the positions of deposit-input points. This study provides valuable insights into tectonic control of depositional systems and sequence architectures in a continental rift basin such as the Fula Sub-basin. 相似文献
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Yongle atoll in the Xisha (Paracel) Archipelago is an isolated carbonate platform developed on Precambrian metamorphic and Mesozoic volcanic rocks since the early Miocene. To identify the 3D stratigraphic architecture and evolution of this platform, 13 high-resolution seismic profiles and shallow-to-deep water multi-beam data were processed and analyzed to reveal seismic facies, sequence boundary reflectors, seismic units, and platform architecture. Nine types of seismic facies were recognized based on their geometry, which included seismic amplitude, continuity, and termination patterns; additionally, six reflections, i.e., Tg, T60, T50, T40, T30, and T20, were identified in the Cenozoic strata. Five seismic units, SQ1 (lower Miocene), SQ2 (middle Miocene), SQ3 (upper Miocene), SQ4 (Pliocene), and SQ5 (Quaternary), were identified from bottom to top across the platform. The platform grew rapidly in the middle Miocene and backstepped in the late Miocene–Pliocene. Here, we discuss the developmental characteristics and evolution of the Yongle Atoll, in combination with drilling wells, which can be divided into four stages: the initiation stage in the early Miocene, the flourishing stage in the middle Miocene, the partial-drowning stage in the late Miocene–Pliocene, and modern atoll in the Quaternary. 相似文献
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A model of submarine channel-levee evolution based on channel trajectories: Implications for stratigraphic architecture 总被引:3,自引:0,他引:3
Zoltán SylvesterAlessandro Cantelli 《Marine and Petroleum Geology》2011,28(3):716-727
Channel-levee systems are frequently interpreted as having a long history of cut-and-fill by channel-shaped features of different scales. Results from a simple geometric model based on a centerline migration algorithm combined with a vertical channel trajectory show that an incising-to-aggrading trajectory of a single channel can produce realistic morphologies similar to systems observed on the seafloor and subsurface, including features such as a basal erosional surface, coeval inner and outer levees, internal erosional boundaries, and terraces draped by inner levee deposits. Channel migration results in composite erosional surfaces that are distinct from topographic surfaces, and their formation does not require larger than usual erosional flows. Many submarine channels interpreted as underfit were probably carved by flows similar to the ones that eroded and deposited the entire channel system. We suggest that the features of most submarine channel-levee systems do not require large temporal variations in flow magnitude but can be explained by a simpler model whereby incision, migration and aggradation of a single channel form over time results in an apparently complex system. 相似文献
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海洋数据的多源性、多态性和多样性以及数据量庞大等特点决定了其不同于其它数据,如何更加合理有效地存储和管理海洋数据,为海洋综合管理信息系统和"数字海洋"原型系统建设提供有力的数据支撑,是一个紧迫需要解决的问题。本文对各类海洋资源、海洋环境、海洋经济、海洋管理等数据进行统一的体系规划,构建统一标准的海洋数据体系框架,以实现国家、省(市)等各级海洋数据的有效管理,满足"数字海洋"海洋信息基础平台建设需要。 相似文献
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海洋Sensor Web(传感器万维网)的研究与开发,对于海洋信息的实时获取、系统集成和高效共享具有重要作用。对Sensor Web的国内外研究现状进行综述,介绍Sensor Web的体系结构和集成标准,并对海洋Sensor Web的研究与开发面临的问题进行分析,对海洋Sensor Web未来的发展方向进行探讨。 相似文献
649.
数字城市共享平台框架的设计与实现(英文) 总被引:2,自引:1,他引:1
This paper proposes a theoretical framework of spatial information sharing in a digital city, and analyzes its technical characteristics.
According to the service-oriented architecture (SOA) framework, a geospatial information sharing platform is put forward.
The spatial information sharing model based on SOA is designed. A prototype platform realizing multiple-source spatial information
sharing based on ArcGIS Server is developed.
Supported by the National Key Basic Research and Development Program of China (No.2004CB318206), the Basic Research of Survey
and Mapping Bureau Project (No.1469990711111). 相似文献
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