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41.
琼东南盆地古近系崖城组海陆过渡相煤系烃源岩已被证实是该盆地的主要气源岩,但由于崖城组煤层具有层数多、单层薄、横向变化快的特点,而难以被识别和预测,尤其是勘探程度较低的深水区.本文利用综合种地质与地球物理法对煤系烃源岩进行更加准确的预测.首先,煤层可通过“三高,三低,一扩”的测井响应特征识别,而炭质泥岩可通过“四高,一低”的特征识别.基于该测井逻辑判断,煤系地层可通过测井曲线的聚类分析进行垂向的自动识别.在井震标的的约束下,煤层组可通过地震数据的“负相位,高吸收因子,低波阻抗和低频”等综合特征进行横向识别.然而,地球物理方法识别的煤系烃源岩分布范围不一定符合成煤的地质规律,因此本文从构造、层序和沉积的角度研究了煤系发育的主控因素约束其分布范围:①古地形及构造沉降控制了海陆过渡相煤系烃源岩在凹陷中的平面发育部位;②相对海平面变化通过控制可容空间变化以及海岸线迁移,从而控制烃源岩的发育规模以及垂向分布——具体的说,可容纳空间的增长速率和泥炭堆积速率的关系是控制煤层形成的最根本因素,在其平衡位置,煤层发育最厚、延伸最大;③原地碎屑的供应和沉积场所与古物源的距离,是制约高丰度烃源岩发育的关键因素,即距离古隆起海岸较近的沉积环境中陆源有机质较为丰富,便可形成高丰度煤系烃源岩.通过上述地质与地球物理联合识别方法,提高了煤系烃源岩发育的预测精度和可信度,为南海西部深水区的早期勘探提供了重要的参考依据.  相似文献   
42.
根据美国Shreveport地区及中国徐州地区2006年的气象探空资料计算了GPS测量中的大气干延迟,将其作为真值与目前常用的普适模型计算的延迟值进行对比,结果表明,目前常用的几种普适模型在美国Shreveport地区的改正效果要明显好于中国徐州地区,直接反映出普适模型更适合北美地区.利用徐州地区2000-2006年的探空数据计算了大气干延迟值,在此基础上,根据地面气象要素建立了徐州地区大气干延迟的局地订正模型.分析表明,局地订正模型的改正效果好于普适模型.  相似文献   
43.
本系统建立在PC机上,用以对电阻率法和激电法各种常用装置作正演、野外数据处理、成图和反演解释。系统适用于微机硬件低配置,同时具有较强和较大数据量的处理功能;采用全汉字界面提示操作,易于使用;系统的结构简单,易于安装和维护。  相似文献   
44.
实用劈窗算法的改进及大气水汽含量对精度影响评价   总被引:2,自引:0,他引:2  
对劈窗算法进行了改进,提高了算法的精度和实用性.对影响大气透过率的大气水汽含量进行了敏感性分析.模拟数据结果表明,劈窗算法对大气水汽含量不敏感,当大气水汽含量误差在-80%~80%变化时,反演的平均精度仍能在1 ℃以下.对实际MODIS影像进行反演的结果与大气模拟数据分析的结论基本一致,这说明适当地利用大气水汽含量的先验知识可以提高劈窗算法反演地表温度的精度.  相似文献   
45.
以2018年"8·11"大安山反倾岩质崩塌为研究对象,通过对大安山地区区域性节理、崩塌及斜坡结构、危岩体变形特征等进行调查研究,运用水力劈裂理论,剖析大安山崩塌机制。研究结果表明:在区域性节理和差异性风化共同作用下,大安山地区发育大量高20~50 m高陡反倾岩质斜坡,为崩塌灾害发生提供充分条件;同时,节理裂隙网络与强硬岩层的空间组合为降雨入渗、运移、储藏提供了良好的地质条件,当遭遇降雨时,雨水沿岩体裂隙渗流并充满裂隙,在降雨停止后短期内,裂隙受高水头作用仍发生水力劈裂,致使裂隙发生扩展贯通,并最终导致危岩体失稳崩塌。  相似文献   
46.
通过分析重力测量精度与磁悬浮系统倾角及仪器支撑腿调节高度之间的关系,结合支撑腿支撑重量大、位移调节精度高的要求,确定采用交流伺服电机驱动高精度电动缸作为支撑腿进行重力仪倾角调平的方案。制作支撑腿调平系统并进行调平实验,倾角调节精度达0.002°,最小位移调节小至2.5μm,找到倾角最小位置,实现重力仪调平功能,同时验证重力测量精度与倾角间的关系,为超导重力仪的调平和高精度重力测量提供参考。  相似文献   
47.
This paper presents a novel semi-submersible(SEMI) platform concept, called the multiple small columns(MSC) SEMI that improves upon the hydrodynamic performance of the conventional SEMI. Unlike the conventional SEMI, the proposed MSC SEMI utilizes multiple small circular columns to support the deck and a large pontoon that increases the structural displacement. The novelty of the MSC SEMI is its reduction of the hydrodynamic load on the structure and suppression of its motion response, particularly in the heave direction. The MSC SEMI has the advantages of increasing the added mass, radiation damping, and natural period of the structure. A comprehensive investigation of the hydrodynamic performance of the novel MSC SEMI is conducted in both the time and frequency domains with a special focus on the resulting hydrodynamic load and motion response. Numerical simulation results demonstrate that the MSC SEMI concept can reduce the hydrodynamic load and motion response and improve the hydrodynamic performance of SEMIs as expected.  相似文献   
48.
A three-dimensional wave radiation stress is introduced into the hydrodynamic sediment coupled model COHERENS-SED, which has been developed through introducing wave-enhanced bottom shear stress, wave dependent surface drag coefficient, wave-induced surface mixing, SWAN, damping function of sediment on turbulence, sediment model and depth-dependent wave radiation stress to COHERENS. The COHERENS-SED is adopted to study the effects induced by wave-induced three-dimensional longshore current on suspended sediment spreading of the Huanghe River (Yellow River) mouth. Several different cases divided by setting different wave parameters of inputting boundary waves are carried out. The modeling results agree with measurement data. In terms of simulation results, it is easy to know that three-dimensional wave radiation stress plays an obvious role when inputting boundary wave height is stronger than 3 m. Moreover, wave direction also affects the sediment spreading rules of the mouth strongly too.  相似文献   
49.
Four images of 1991 AVHRR, 2003 and 2007 MODIS were used to extract waterlogging inundated water of three years, and three inundated water maps were overlaid to estimate waterlogging affected frequency. Based on waterlogging affected frequency, waterlogging hazard of pixel scale was assessed. According to the weighed score of area percentage of different waterlogging affected frequency in 13 counties/cities of Lixiahe region, waterlogging hazard rank of every county/city was assessed. Waterlogging affected frequency map and 1 km× 1 km grid landuse map were used to assess waterlogging risk of pixel scale; and then waterlogging risk rank of every county/city was assessed by the similar method by which waterlogging hazard rank of every county/city was assessed. High risk region is located mainly in core zone of Lixiahe hinterland, medium risk region is adjacent to high risk region, and low risk region is located in the most outlying area of risk zone and mainly in south to middle part of Lixiahe region. Xinghua and Gaoyou belong to high risk city, Jiangyan belongs to medium risk city, and the other counties/cities have low or lower waterlogging risk. The method of assessing waterlogging risk in this paper is simple and applicable. This paper can provide guidance for the waterlogging risk analysis in broader area of Huaihe River Basin.  相似文献   
50.
The Ordos Basin is well-known for the coexistence of oil, natural gas, coal and uranium. However, there has been little research to discuss the genetic relationship between them. In this paper, a case study of the Zaohuohao area in Dongsheng, Inner Mongolia, China, is conducted to investigate the genetic relationship between the natural gas and the uranium accumulation. Fluid inclusion data from the uranium-bearing sandstone samples indicate that the fluid inclusions formed in a gas-water transition zone. Using the homogeneous temperatures of aqueous inclusions coeval with hydrocarbon-bearing inclusions, combined with the buried history and paleo-temperature data, the gas-water transition zone reached the area at about 110 Ma. On the basis of this, the contents of Uranium (U) and Total Organic Carbon (TOC) of the samples were analyzed, and there was no obvious relation between them. With regard to the available data from both publications and this study, it is found that the U mineralization has a spatiotemporal accordance with the gas-water dispersal zone. Thus, it is believed that the natural gas in the gas-water zone is an effective reducer to the U-bearing ground water abundant in oxygen, which is the main factor to U accumulation. This result can be used as the reference to the U mines predicting and prospecting.  相似文献   
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