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51.
松辽盆地地热场   总被引:3,自引:0,他引:3  
吴乾蕃 《地震研究》1991,14(1):31-40
本文实测了65口井的地热数据,从中取得17个大地热流值,松辽盆地地热场具有中部高边部低,并呈环状分布,该区地热具有高特征的地质发展历史。分区计算盆地的沉积岩层、花岗岩质层和玄武岩质层各底部的温度和热流值,也都具有中部高边部低的变化趋势。分析了盆地地热场受影响的状况和地热高的主要原因。还分析了盆地地热场与构造活动性、地震活动性、重磁力场、岩石圈厚度的关系,以及与石油生成、运移和富集的关系。  相似文献   
52.
岩石的热惯量研究   总被引:1,自引:0,他引:1  
本文阐述了热惯量的物理意义及其在地质遥感中的作用。在测得23种岩石热物理性质的有关参数──热传导率、热容量和密度的基础上,计算并列表给出了岩石的热惯量值和热扩散系数等基础数据。文中分析讨论了沉积岩、变质岩和岩浆岩岩石的热惯量变化由高到低的初步规律。取得了碳酸盐岩和砂岩类等沉积岩和沉积浅变质岩的热惯量差异的结果,指出了它们的易区分性;也指出了中-酸性、碱性岩浆岩之间的热惯量值差异较小,不易区分。  相似文献   
53.
文章证明了模式在预报时段的位温误差,是由于在模式大气和真实大气中,该时段内位温变化过程的不同而造成的。还证明了原始方程的无加速定理对各强迫因子的线性分解同样适用于研究NWP模式热量误差的成因。对国家气象中心T42L9模式1992年1月和7月预报结果的动力诊断表明,模式对纬向位温分布具有较好的预报能力,但在各纬带也存在明显的误差。通过无加速定理的分解分析,研究了这些误差的成因及改善模式的可能途径。  相似文献   
54.
下庄矿田基底的控矿作用及其有关地质问题   总被引:4,自引:2,他引:4  
徐达忠  薛振华 《铀矿地质》1994,10(3):150-155
本文提出武夷及其邻区存在两个裂陷槽及一裂隆,鹰潭-南城-安远-河源韧性断裂带为东部的火山岩型与西部的花岗岩型铀矿床的地质分界线,指出了加里东运动在本区的突出作用是使裂隆基底岩石发生混合花岗岩化作用。根据下庄矿田及其外围发现较深变质的岩石和较大规模韧性剪切糜棱岩带,得出下庄矿田是古老基底加里东热穹隆区多次构造、岩浆活动的产物。由于铀成矿作用赋存于初、脆性两种构造中,建议重新划分矿化类型以指导勘查工作。  相似文献   
55.
Four rock types (basalt, sandstone, granite, and chalk) are examined with respect to the maximum surface temperatures which they experience when subjected to similar conditions of exposure. Rock temperature measurements are reported for an urban environment and for two experimental situations in which an infrared lamp is used to simulate heating under cold and hot conditions. Differences in rock temperatures are discussed with reference to thermal rock properties (albedo, specific heat capacity, and thermal conductivity). Some natural situations are suggested in which thermal rock properties could conceivably play a role in determining the extent to which rocks would be affected by particular weathering processes.  相似文献   
56.
高世玉  张廉强 《中国地震》1995,11(3):204-211
本文根据白家疃台60年代以来的短周期地震记录图,分析了区域震相的强度比。研究表明:Sn/Lg波的强度比波传播路径上岩石层热结构、热状态及强地震活动等均有相关性,并就这种相关性对于强地震成因及其预测研究的直接意义进行了讨论。  相似文献   
57.
Seasonal and diurnal variability of thermal structure in the coastal waters off Visakhapatnam has been examined in relation to the flow field and surface winds utilizing the hourly data of temperature and currents taken at a fixed location over a tidal cycle at monthly intervals. The coastal currents in the pre-monsoon period and strong near-surface winter cooling processes affect the thermal structure of the coastal sea. Upwelling which is predominant during March to May with an intermittent relaxing event helps in the development of a strong layered thermal structure while convective mixing due to winter inversions during November to February causes weak thermal gradients in the water column.  相似文献   
58.
As part of the International Continental Scientific Drilling Program (ICDP), the 1.5-km-deep borehole Yaxcopoil-1, located in the Chixculub meteor impact structure in Mexico, has undergone further study after drilling operations ceased. Temperature logs were repeated ten times at intervals 0.3–0.8, 15, 24 and 34 months after borehole shut-in. The logs bear a distinct signature of transient heat transfer by groundwater flow manifested by a gradual distortion of the linear temperature profile when a cold wave of 0.8–1.6°C amplitude was detected propagating downward from 145 to 312 m at a rate of 4–6 m/month. To understand the nature of this moving anomaly, a 20-day monitoring of the cold wave was carried out at a depth of 307 m that showed further cooling of 0.6°C during the first 16 days of the passage followed by temperature stabilisation. As an explanation of this unusual phenomenon, a theory is proposed, whereby the drilling mud has accumulated within the overlying and cooler highly porous and permeable karstic rocks during the drilling and migrates downward. The observed migration rate suggests a permeability higher than 10?11 m2. This indicates a high vulnerability to contamination of the only freshwater aquifer in the Yucatan region.  相似文献   
59.
Natural underground coal fires are fires in coal seams occurring subsurface. The fires are ignited through a process named spontaneous combustion, which occurs based on a natural reaction but is usually triggered through human interaction. Coal mining activities expose coal to the air. This leads to the exothermal oxidation of the carbon in the coal with the air's oxygen to CO2 and – under certain circumstances – to spontaneous combustion. Coal fires occur in many countries world wide – however, currently the Chinese coal mining industry faces the biggest problems with coal fires. Coal fires destroy the valuable resource coal and furthermore lead to many environmental degradation phenomena such as the deterioration of surrounding vegetation, land subsidence and the emission of toxic gasses (CO, N2O). They additionally contribute to the emission of green house relevant gasses such as CO2 and CH4 to the atmosphere.In this paper we present thermal characteristics of coal fires as measured in-situ during a field campaign to the Wuda coal fire area in south-central Inner Mongolia, China. Thermal characteristics include temperature anomaly measurements at the surface, spatial surface temperature profiles of fire areas and unaffected background areas, diurnal temperature profiles, and temperature measurements inside of coal fire induced cracks in the overlying bedrock. For all the measurements the effects of uneven solar heating through influences of slope and aspect are considered.Our findings show that coal fires result in strong or subtle thermal surface anomalies. Especially the latter can easily be influenced by heating of the surrounding background material through solar influences. Temperature variation of background rocks with different albedo, slope, aspect or vegetation cover can substantially influence the detectability of thermal anomalies. In the worst case coal fire related thermal anomalies can be completely masked by solar patterns during the daytime. Thus, night-time analysis is the most suitable for thermal anomaly mapping of underground coal fires, although this is not always feasible. The heat of underground coal fires only progresses very slowly through conduction in the rock material. Anomalies of coal fires completely covered by solid unfractured bedrock are very weak and were only measured during the night. The thermal pattern of underground coal fires manifested on the surface during the daytime is thus the pattern of cracks and vents, which occur due to the volume loss underground and which support radiation and convective energy transport of hot gasses. Inside coal fire temperatures can hardly be measured and can only be recorded if the glowing coal is exposed through a wider crack in the overlaying bedrock. Direct coal fire temperatures measured ranged between 233 °C and 854 °C. The results presented can substantially support the planning of thermal mapping campaigns, analyses of coal fire thermal anomalies in remotely sensed data, and can provide initial and boundary conditions for coal fire related numerical modeling.In a second paper named “Thermal Characteristics of Coal Fires 2: results of measurements on simulated coal fires” [Zhang J., Kuenzer C., Tetzlaff A., Oettl D., Zhukov B., Wagner W., 2007. Thermal Characteristics of Coal Fires 2: Result of measurements on simulated coal fires. Accepted for publication at Journal of Applied Geophysics. doi:10.1016/j.jappgeo.2007.08.003] we report about thermal characteristics of simulated coal fires simulated under simplified conditions. The simulated set up allowed us to measure even more parameters under undisturbed conditions — especially inside fire temperatures. Furthermore we could demonstrate the differences between open surface coal fires and covered underground coal fires. Thermal signals of coal fires in near range thermal remotely sensed imagery from an observing tower and from an airplane are presented and discussed.  相似文献   
60.
天然气水合物的地热研究进展   总被引:8,自引:0,他引:8  
天然气水合物的地热研究在以下几个方面都取得了重要进展,热流与似海底反射层的关系,水合物稳定带的研究;水合物热物理参数的确定;水合物形成过程中的热状态;热导率的应用,指出了今后水合物的地热学研究方向。  相似文献   
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