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101.
Radon Precursory Signals for Some Earthquakes of Magnitude > 5 Occurred in N-W Himalaya: An Overview
Vivek Walia Hardev Singh Virk Bikramjit Singh Bajwa 《Pure and Applied Geophysics》2006,163(4):711-721
The N-W Himalaya was rocked by a few major and many minor earthquakes. Two major earthquakes in Garhwal Himalaya: Uttarkashi
earthquake of magnitude Ms= 7.0 (mb = 6.6) on October 20, 1991 in Bhagirthi valley and Chamoli earthquake of Ms= 6.5 (mb = 6.8) on March 29, 1999 in the Alaknanda valley and one in Himachal Himalaya: Chamba earthquake of magnitude 5.1 on March
24, 1995 in Chamba region, were recorded during the last decade and correlated with radon anomalies. The helium anomaly for
Chamoli earthquake was also recorded and the Helium/Radon ratio model was tested on it. The precursory nature of radon and
helium anomalies is a strong indicator in favor of geochemical precursors for earthquake prediction and a preliminary test
for the Helium/Radon ratio model. 相似文献
102.
103.
结合水氧、应力观测资料对甘肃武山地区地下流体化学特征(水化学、气体化学)与构造应力关系进行了定量计算并给出了二者之间的数学关系。 相似文献
104.
105.
居民住宅和单位用房中氡的来源及有关问题 总被引:1,自引:0,他引:1
本文讨论了人类正常生活环境中氡的来源及产生的机制、氡对人体的侵害、以及防氡降氡的某些措施等问题。 相似文献
106.
氡,汞测量用于断裂活动性和分段的研究 总被引:25,自引:1,他引:25
作者首先给出海原活动断裂带从边沟至硝口的3条较长次级剪切断层,干盐池拉分盆地和边沟推挤构造区内的断层,以及尾端挤压构造区内的六盘山东麓逆断层的气氡,气汞浓度测量结果,然后分析了断层气浓度与断层活动性之间的关系,研究结果表明,测试条件大体一致的基础上,气氡,气汞浓度与断层活动性之间有着明显的对应关系,从而证明了断层气测量方法对于活断层分段和活动性研究是一种有效的手段。 相似文献
107.
本文对本刊1986年第5期刊载叶树林同志的文章提出几点意见。指出该文所述氡的分布模式与同文所述实践结果相悖。同时还指出表示氡分布的数学模型的应用条件和该数学模型的立条件不同以及后者建立的前提条件违背了客观实际。 相似文献
108.
H. A. Wollenberg A. R. Smith D. F. Mosier S. Flexser M. Clark 《Pure and Applied Geophysics》1984,122(2-4):327-339
In the Long Valley caldera, where seismicity has continued essentially uninterrupted since mid-1980 and uplift is documented, samples of water from hot, warm, and cold springs have been collected since September, 1982, and their222Rn concentrations analyzed. Concurrently, rocks encompassing the hydrologic systems feeding the springs were analyzed for their radioelement contents, because their uranium is the ultimate source of the222Rn in the water.The222Rn concentration in the springs varies inversely with their temperature and specific conductance. High concentrations (1500 to 2500 picocuries per liter) occur in dilute cold springs on the margins of the caldera, while low contents (12 to 25 pCi/l) occur in hot to boiling springs. Springwater radon concentrations also correlate slightly with the uranium content of the encompassing rocks.A continuous monitoring system was installed in August, 1983, at a spring issuing from basalt, to provide hourly records of radon concentration. A gamma detector is submerged in a natural pool, and we have observed that the radioactivity measured in this manner is due almost entirely to the222Rn concentration of the water. Initial operation shows diurnal and semidiurnal variations in the222Rn concentration of the springwater that are ascribed to earth tides, suggesting that those variations are responding to small changes in stress in the rocks encompassing the hydrologic system. 相似文献
109.
M. H. Shapiro A. Rice M. H. Mendenhall J. D. Melvin T. A. Tombrello 《Pure and Applied Geophysics》1984,122(2-4):309-326
Four techniques (pattern recognition, Fourier transformation, cross-correlation, and multiple linear regression) have been used to recognize nontectonic environmental factors affecting groundwater radon data collected by the Caltech automated geochemical network. Several factors, including air temperature, rainfall, water level, carbon dioxide concentration in the water, and barometric pressure, were found to correlate with radon level at some stations in the network. For example, approximately 60% of the variance in radon signal at one site studied (Pacoima) could be accounted for by nontectonic influences. However, it was not possible to correlate all the observed changes in radon concentration with nontectonic environmental variables. Some of the observed radon anomalies did appear to be related to either regional changes in tectonic strain or some individual earthquakes. A model is developed to account for spike-like increases in radon caused by carbon dioxide emission. 相似文献
110.
本文研究河源4号孔水氡值变化规律,在干扰排除的情况下,运用相关距平分析方法分析其正常年变的变化,提取资料的异常信息与地震的映震关系,得出该方法对本区地震的对应关系比较明显。 相似文献