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91.
南京直立人的发现与研究的主要意义在于深入探讨了南京汤山葫芦洞古人类头骨的性质、性别、年龄、病理、环境、遗传基因和时代等一系列学术问题。对古人类在南京地区的发现、发展演化及其与国内外已知直立人的关系等方面的研究提供了重要证据。  相似文献   
92.
安徽洞穴资源及其开发利用   总被引:3,自引:0,他引:3  
:通过对安徽143处洞穴及洞群的调查 ,阐明安徽洞穴资源分布特征 ,洞穴开发产生的经济效益和社会效益 ,开发潜力及远景。提出加强洞穴资源保护及合理开发利用的建议  相似文献   
93.
凤城市赛马镇风洞洞穴特征及发育基本条件   总被引:1,自引:0,他引:1  
陈为民  姚明和  李洋  陈跃月 《地质与资源》2006,15(2):133-136,141
赛马镇风洞是我国东北规模较大的岩溶洞穴,洞长在2000m以上,已探测长度1265m.风洞具有纵坡降较小、支洞繁多、形态奇异及国内罕见的溶蚀景观“天锅”等特征.岩性、构造、水文地质特征等是控制洞穴发育的基本条件.风洞的发育约始于中更新世40万年前.  相似文献   
94.
Recharge processes of karst aquifers are difficult to assess given their strong heterogeneity and the poorly known effect of vadose zone on infiltration. However, recharge assessment is crucial for the evaluation of groundwater resources. Moreover, the vulnerability of karst aquifers depends on vadose zone behaviour because it is the place where most contamination takes place. In this work, an in situ experimental approach was performed to identify and quantify flow and storage processes occurring in karst vadose zone. Cave percolation monitoring and dye tracing were used to investigate unsaturated zone hydrological processes. Two flow components (diffuse and quick) were identified and, respectively, account for 66% and 34% of the recharge. Quickflow was found to be the result of bypass phenomenon in vadose zone related to water saturation. We identify the role of epikarst as a shunting area, most of the storage in the vadose zone occurring via the diffuse flow component in low permeability zones. Relationship between rainfall intensity and transit velocity was demonstrated, with 5 times higher velocities for the quick recharge mode than the diffuse mode. Modelling approach with KarstMod software allowed to simulate the hybrid recharge through vadose zone and shows promising chances to properly assess the recharge processes in karst aquifer based on simple physical models.  相似文献   
95.
96.
瞬变电磁法在煤矿水患区预测中的应用   总被引:1,自引:0,他引:1  
在青杠林煤矿工作中,利用MSD-1脉冲瞬变电磁仪,选用100m×100m正方形重叠回线装置,观测时窗8~25920μs,采样道数40道进行数据采集。经数据处理,获得该区多测道剖面图及虚拟全区视由阻率剖面图,从中解释其含水岩溶管道3处,含水岩溶空洞2处,节理、裂隙5条。根据依照水患危险程度划分标准该区岩溶管道、空洞的位置及节理、裂隙的贯穿深度,将该区定为中等程度隐患预测区。  相似文献   
97.
晏胜荣  贺飞 《探矿工程》2008,35(9):76-79
本区间因隧道下穿南航酒店和火车站地中海商场及停车场,大部分区域无法实施钻探。而由周边地质资料及施工所反映的情况推测,该区域有存在空洞的可能。未探明的空洞可能对盾构机掘进造成不利影响,如盾构机栽头、地层塌陷等。因此,在盾构机通过未探明区域前必须进行探测和预处理,以指导盾构机掘进。  相似文献   
98.
The Tahe Oilfield is a complex petroleum reservoir of Ordovician carbonate formation and made up of spatially overlapping fracture-cavity units. The oilfield is controlled by a cave system resulting from structure-karst cyclic sedimentation. Due to significant heterogeneity of the reservoir, the distribution of oil and water is complicated. Horizontally, a fresh water zone due to meteoric water can be found in the north part of the Akekule uplift. A marginal freshening zone caused by water released from mudstone compaction is found at the bottom of the southern slope. Located in a crossformational flow discharge zone caused by centripetal and the centrifugal flows, the main part of the Tahe Oilfield, featuring high salinity and concentrations of CI^- and K^++Na^+, is favorable for accumulation of hydrocarbon. Three types of formation water in the Tahe Ordovician reservoir are identified: (1) residual water at the bottom of the cave after oil and gas displacement, (2) residual water in fractures/pores around the cave after oil and gas displacement, and (3) interlayer water below reservoirs. The cave system is the main reservoir space, which consists of the main cave, branch caves and depressions between caves. Taking Cave System S48 in the Ordovician reservoir as an example, the paper analyzes the fluid distribution and exploitation performance in the cave system. Owing to evaporation of groundwater during cross-formational flow, the central part of the main cave, where oil layers are thick and there is a high degree of displacement, is characterized by high salinity and Br^- concentration. With high potential and a long stable production period, most wells in the central part of the main cave have a long water-free oil production period. Even after water breakthrough, the water content has a slow or stepwise increase and the hydrochemistral characteristics of the produced water in the central part of the main cave are uniform. From the center to the edge of the main cave, displacement and enri  相似文献   
99.
The Tahe Oilfield is a complex petroleum reservoir of Ordovician carbonate formation and made up of spatially overlapping fracture-cavity units. The oilfield is controlled by a cave system resulting from structure-karst cyclic sedimentation. Due to significant heterogeneity of the reservoir, the distribution of oil and water is complicated. Horizontally, a fresh water zone due to meteoric water can be found in the north part of the Akekule uplift. A marginal freshening zone caused by water released from mudstone compaction is found at the bottom of the southern slope. Located in a cross- formationai flow discharge zone caused by centripetal and the centrifugal fows, the main part of the Tahe Oilfield, featuring high salinity and concentrations of CI- and K Na , is favorable for accumulation of hydrocarbon. Three types of formation water in the Tahe Ordovician reservoir are identified: (1) residual water at the bottom of the cave after oil and gas displacement, (2) residual water in fractures/pores around the cave after oil and gas displacement, and (3) interlayer water below reservoirs. The cave system is the main reservoir space, which consists of the main cave, branch caves and depressions between caves. Taking Cave System $48 in the Ordovician reservoir as an example, the paper analyzes the fluid distribution and exploitation performance in the cave system. Owing to evaporation of groundwater during cross-formational flow, the central part of the main cave, where oil layers are thick and there is a high degree of displacement, is characterized by high salinity and Brconcentration. With high potential and a long stable production period, most wells in the central part of the main cave have a long water-free oil production period. Even after water breakthrough, the water content has a slow or stepwise increase and the hydrochemistral characteristics of the produced water in the central part of the main cave are uniform. From the center to the edge of the main cave, displacement and enrichment of oil/gas become weaker, residual water increases, and the salinity and concentration of Br- decrease. At the edge of the main cave, although the wells have a high deliverability at the beginning with a short stable production period and water-free production period. After water breakthrough, the pressure and deliverability drop quickly, and the water content rises quickly. The hydrochemistrai characteristics of the produced water are relatively uniform. Wells in the branch caves have a relatively low deliverability at the beginning, with a short stable production period. Water breakthrough appears quickly and then the pressure and deliverability drop quickly. The salinity and concentrations of CI-and K Na are usually fluctuant or descend slowly in the produced water. Wells in low areas of ancient karst have a low deliverability and a short stable production period. The yield drops quickly and the water content is high, while the characteristics of the produced water may vary significantly well to well. The salinity and concentrations of CI- and K, Na in the produced water are usually fluctuant with a precipitous decline.  相似文献   
100.
碳酸盐岩中岩溶洞穴的形成条件及预测方法初探   总被引:1,自引:0,他引:1  
  相似文献   
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