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991.
本文主要论述热源构造的特征、活动规律及其与铀矿在时间、空间和成因上的密切联系。并以华南地区三大热源构造系为例,说明热源构造的铀成矿特点、分布规律,将与热源构造有关的铀成矿机制概括为“混合-结合-中合”,即“三合式”成矿模式。 相似文献
992.
The short-term variability observed in the near surface meteorological parameters and in the vertical thermal structure of
the upper layers of the northern Bay of Bengal during a weak monsoonal regime is examined with the aid of time series measurements.
The variability of the mixed layer depth is interpreted in terms of forced mixing caused by the surface wind stress and free
mixing by buoyancy flux, Ekman pumping controlled by the curl of the surface wind stress, convergence associated with a clockwise
gyral circulation and stratification caused by freshwater discharges from rivers. The daily-averaged current vectors in the
upper layers indicate the presence of clockwise gyral circulation in the polygon area. 相似文献
993.
COMPILATION OF HEAT FLOW DATA IN THE CHINA CONTINENTAL AREA (2nd Edition 总被引:16,自引:4,他引:16 下载免费PDF全文
During the last 2 years, heat flow data increased significantly in China as a result of implementation of many comprehensive geodynamic (including geothermal) projects and GGT project in China. In this paper, a total of 366 reliable heat flow data is collected from published and in press sources in the Compi-ilation of Heat Flow Data in the China Continental Area (2nd edition). Statistic analysis of these data shows that the heat flow values in China continental area vary from 20 to 14... 相似文献
994.
Alan M. Jessop 《Pure and Applied Geophysics》1990,133(2):251-267
Temperature, temperature gradient and heat flow, derived from four wells in the Western Canada Sedimentary Basin have been compared with similar quantities derived from maps constructed from industrial data. Individual industrial temperature data may differ from the high-resolution temperature log by up to 30 K, but linear regression of the collected data agrees within 10 K at all points observed. Some evidence suggests that measured conductivities, using drill-cuttings, are biased toward average values. Derived heat flows show agreement of heat flow within 10% within the Mesozoic section. In the Paleozoic section differences are greater, and more varied, with insufficient data for general conclusions. Both styles of measurement provide opportunities for interpretation, each contributing to thermal analysis of sedimentary basins. 相似文献
995.
利用上海地区1961—1965年的热量平衡资料以及常规的气候资料,分析了该地区热量平衡各分量的年、月、日变化规律,进一步阐明了我国湿润地区在地表热量平衡过程中,潜热占绝对优势的特征。 相似文献
996.
中国东南地区岩石生热率分布特征 总被引:26,自引:0,他引:26
基于500余块岩石样品的生热率实测值和前人的研究成果,本文系统地分析了中国东南地区不同时代、不同岩性和不同大地构造单元岩石生热率的分布特征,揭示出华南沉积区地层在晚元古代一寒武纪和侏罗纪出现两次生热率高峰,花岗岩具有异常高的生热率背景。岩石生热率以粤中-赣南为核心,向外扩展呈下降趋势;政和-大埔断裂带西侧生热率明显高于东侧火山岩出露区;扬子沉积区明显低于华南区。按区域岩石生热率分布可以划分为三个区:南区生热率背景值超过2.8μW/m3,东区介于2.1~2.8μW/m3,北区普遍低于2.1μW/m3。岩石生热率分布在一定程度上反映了区域基底生热元素的丰度和岩浆活动的强度。 相似文献
997.
本文分析了南海市大气污染源特征及大气环境质量变化,探讨了南海市经济发展对大气环境的影响,在此基础上提出对大气环境保护的对策。 相似文献
998.
西安市城市边界层热岛的数值模拟 总被引:11,自引:0,他引:11
本文使用非定常二维边界层大气动力和热力方程组数值模式,结合西安市1983年秋冬季城郊气象场的观测资料及能源耗量,分析计算了西安城市热岛热力场的特性和强度,并评估了由于城市能源消耗总量的增加对未来城市热岛的影响。 相似文献
999.
Metal foil collection/flash desorption/flame photometric detection (MFC/FD/FPD) was one of the analytical methods used to measure emissions of gaseous, sulfur-containing compounds from several terrestrial natural sources during a cooperative field program in the summer of 1985. Nonspeciated, total sulfur gas emissions were determined by using the MFC/FD/FPD technique in combination with a Nafion Perma-Pure drying device to sample air from three designs of dynamic enclosure chambers. These enclosures were placed over various soil orders and vegetation in the vicinity of field sites in Iowa and Ohio previously examined during the 1977–80 SURE study of biogenic sulfur fluxes. Because of the sensitivity and detection characteristics of the MFC/FD/FPD technique, it was possible to obtain measurements on enclosure air samples that were collected for relatively short time periods,. e.g., 1 to 5 min. The magnitudes of these time-resolved, total sulfur gas emissions are correlated exponentially with internal enclosure air temperatures. Potential errors and uncertainties associated with this application of the MFC/FD/FPD methodology are assessed.The total sulfur gas flux values obtained from this study and the SURE program are compared. Unquantified sources of error in the current two parameter extrapolation model used to calculate regional and global terrestrial source strengths of biogenic sulfur emissions are also summarized and are shown to prevent a reliable estimate of overall uncertainty limits in the resultant inventory. 相似文献
1000.
A new gas chromatographic technique with a modified photoionization detector connected in series with a conventional flame ionization detector was used to determine low concentrations of atmospheric hydrocarbons in remote atmospheres. Average mixing ratios of five aromatic hydrocarbons measured between 42°N and 30°S latitude in the Pacific Ocean in October/November 1983 were highest in the Northern Hemisphere. The average mixing ratios in the northern and southern marine atmospheres were 49±25 ppt (n=35) and 10±2 ppt (n=21) for benzene, 20±12 ppt (n=32) and 5.6±1.6 ppt (n=12) for toluene, 7.6±3.7 ppt (n=35) and 3.7±1.6 ppt (n=21) for ethylbenzene, 25±12 ppt (n=35) and 13±5 ppt (n=20) for the sum of m- and p-xylenes, and 14±6 ppt (n=35) and 6.6±3.0 ppt (n=21) for o-xylene, respectively. The first latitudinal gradients for these five aromatic compounds are reported. Benzene and toluene mixing ratios measured between July 1982 and October 1983 at a rural, mid-latitude continental site in eastern Washington state gave average values of 226±108 ppt and 133±84 ppt, respectively, with higher wintertime than summertime benzene levels. These continental samples gave calculated air mass ages averaging six days based on benzene-to-toluene ratios. 相似文献