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241.
应用地球化学方法是地热、温泉勘查中广泛采用的有效手段之一。以麻林桥低温热水为例,说明土壤中的汞、砷、硼微量元素的富集规律,这些微量元素对寻找地下导热构造有明显的指示作用。 相似文献
242.
243.
为了解决鲁北平原区农村冬季清洁供暖问题,扩大地下水地源热泵系统的应用规模,以区内广泛发育的咸水体为研究目标,在简述第四纪地层特征的基础上,阐明了第四纪含水砂层与咸水体的分布特征,总结了区内以往开展的4个浅层地热能勘查项目所施工的水文地质勘探孔抽水试验与回灌试验成果。结果表明: 研究区咸水含水层单井涌水量320~475 m3/d,单位涌水量12.76~28.3 m3/(d·m),自然回灌条件下单井回灌量30~56 m3/d,单位回灌量5.85~17.5 m3/(d·m); 单眼开采井可供暖面积为3 481.02 m2,可满足约35户农村住宅的冬季供暖需求; 研究区在进行浅层地热能开发时建议优先选择地下水地源热泵系统,对于供暖/制冷能耗需求较小的农村单户建筑,可选择地埋管地源热泵系统进行分散式供暖/制冷。 相似文献
244.
气候系统内极区热汇与热带海洋热源之间的相互作用(英) 总被引:2,自引:1,他引:1
The anomalous change of two polar sea ice and tropical ocean SST is a very important index for global climate monitoring and prediction. In this paper, the wave resonance principle is used to calculate month by month running cross couple correlation coefficient time series between sea ice in different sea area of two Polars, as well as between them and five elements of E1 Nino events, to analyze their variation features, and to find out their resonance periods. The resonance period of two waves is just the strongest interaction period.Some results are concluded as follows. 1) The Arctic sea ice to the Pacific-side (NPI1) and Atlantic-side (NP12) show a strong positive-negative feedback impact each other to the Antarctic Ross Sea ice (SPI2) with equal intensity. 2) Both NPI1 and NPI2 give a strong positive and negative feedback to the Antarctic Wedded Sea ice (SPI3) while it is rather weak in convercse status. It means that, the Arctic sea ice plays a leading and controlling role on the Wedded Sea ice. 3) SST of Nino 4 area in thecentral equatorial Pacific has a best resonance period with SPI2 with cycle period of 132 months. It closely relates to quasi-11 years oscillation period of both SST of Nino 4 area and SPI2. SST of Nino 4 has also a resonance period to SPI3 with cycle of 61 months. There also exist strong interaction periods between the Antarctic sea ice and other elements of ENSO event but weaker than SST of Nino 4 area. 相似文献
245.
城市区域屋顶上与地上的风速和温度特征分析 总被引:17,自引:5,他引:12
以低纬的城市昆明为研究对象,利用城内外屋顶上和地上的风速和温度实测资料,分析了研究较少的,做为城市第二热力面的屋顶面附近的风度温特征,变化规律及其与地上的差异,得到了一些有益的结果。 相似文献
246.
The thermoelastic response due to a time-dependent rectangular heat source in a semi-infinite medium is analyzed. The problem originates from studies of nuclear waste repositories in rock. Canisters containing heat-emitting nuclear waste are deposited over a large rectangular area deep below the ground surface. The solution for a time-dependent heat source is obtained from the corresponding instantaneous heat source by superposition. The thermoelastic problem for the instantaneous rectangular heat source in a infinite surrounding is solved exactly. An important step is the introduction of so-called quadrantal heat sources. The solution for the rectangle is obtained from four quadrantal solutions. The solution for the quadrantal heat source depends on the three dimelasionless coordinates only. Time occurs in the scale factors only. The condition of zero normal and shear stresses at the ground surface is fulfilled by using a mirror heat source and a boundary solution. The boundary solution accounts for the residual normal stress at the ground surface. Using a Hertzian potential, a surprisingly simple solution is obtained. The final analytical solution is quite tractable considering the complexity of the initial problem. The solution may be used to test numerical models for coupled thermoelastic processes. It may also be used in more detailed numerical simulations of the process near the heat sources as boundary conditions to account for the three-dimensional global process. 相似文献
247.
Lithospheric Geothermal Structure in Yunnan, China 总被引:2,自引:0,他引:2
Zhou Zhenheng Xiang Caiying and Deng WanmingSeismological Bureau of Yunnan Province Kunming China Institute of Geology Chinese Academy of Sciences Beijing China 《中国地震研究》1998,(1)
In this paper,the characteristics of the lateral variations of the deep heat flow and Hthospheric geotemperature distribution in Yunnan have been studied,and the lithospheric geothermal structure has been divided into three types,i.e.the geothermal structure in the typical modern tectonically active region,transitional geological region and stable geological region.Finally,the relationship between the geotherm and seismicitv has been discussed. 相似文献
248.
渭河断陷赋存丰富的地下热水资源.本文叙述了该区地热分布特征,阐明了区内地质构造、深部地质条件对地下热水赋存和水温、水量变化的控制作用,兼论了西安城郊区及地热赋存的地质构造背景.对指导当前和今后这一地区地热资源的开发利用和管理工作有重要意义。 相似文献
249.
Arthur H. Lachenbruch 《Pure and Applied Geophysics》1978,117(1-2):34-50
In regions of tectonic extension, vertical convective transport of heat in the lithosphere is inevitable. The resulting departure of lithosphere temperature and thickness from conduction-model estimates depends upon the mechanical mode of extension and upon how rapidly extension is (and has been) taking place. Present knowledge of these processes is insufficient to provide adequate constraints on thermal models. The high and variable regional heat flow and the intense local heat discharge at volcanic centers in the Basin and Range province of the United States could be accounted for by regional and local variations in extensional strain rate without invoking anomalous conductive heat flow from the asthenosphere. Anomalous surface heat flow typical of the province could be generated by distributed extension at average rates of about 1/2 to 1%/m.y., similar to rates estimated from structural evidence. To account for higher heat flow in subregions like the Battle mountain High, these rates would be increased by a factor of about 3, and locally at active bimodal volcanic centers, by an order of magnitude more. 相似文献
250.
K. Blümel 《Boundary-Layer Meteorology》1998,86(2):193-232
By means of the algorithm presented here, the temporal course H(t) and the daily mean H¯ of the sensible heat flux H can be estimated from measurements of the thermodynamic surface temperature (as a function of time) and from a one-time-of-day air temperature observation. In addition to these temperatures, one needs estimates for daily mean wind speed, for the roughness lengths of momentum and heat transfer, and for the displacement height. First, a quite general solution of the equation for heat conductance (equation for the vertical profile of potential temperature (z,t)) in the dynamic sublayer will be presented. The undetermined parameters in this solution will be defined with the aid of the above mentioned measurements. The influence of horizontal advection will be taken into account. After that, the sensible heat flux can be evaluated from the temperature difference between surface and air with the well known resistance formulae. In this paper the algorithm is derived for areas with homogeneous surfaces, i.e., with uniform surface temperatures. Finally, the method will be verified by measurements taken during the field campaigns HIBE 89 (Hildesheimer Börde in Germany) and EFEDA 91 (Spain). The root mean square errors (RMSE) for the comparison between measurement and model with regard to the temperature difference of surface and air amount to one or two degrees Kelvin, and the error of H¯ reaches 10 to 25 per cent. The method can be used to determine the sensible heat flux from measurements of surface temperatures by satellites (e.g., METEOSAT), but can also be applied to ground based measurements. For instance, horizontal temperature advection can be estimated from measurements at a single location, especially if more than one near-surface air temperature is available. The procedure can be generalized for larger areas, which consist of various surface types with different surface temperatures. This generalization of the algorithm is in progress and will be addressed in a subsequent paper. It will allow us to improve the estimates for H(t) by means of temperature measurements from, e.g., NOAA/AVHRR or LANDSAT/TM, taking into account the heterogeneity of the area that is contained in one METEOSAT pixel. 相似文献