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101.
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
102.
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
103.
Results of geothermal gradient measurements in 44 localities in Brazil are presented. The Precambrian shield areas are found to be characterized by relatively low temperature gradients in the range 6 to 20°C/km while younger sedimentary basins are characterized by gradients in the range 15 to 35°C/km. An inverse correlation between geothermal gradient and tectonic age has been observed. This as well as the favourable hydrological conditions suggest that the best sites for extraction of geothermal energy in Brazil are the younger sedimentary basins. The Parana Basin is found to offer at present the best site for extraction of geothermal energy in Brazil. Preliminary examination of the temperature distributions in the major aquifer (Botucatu sandstone) suggest that this aquifer contains substantial quantities of warm waters in the temperature range 40 to 90°C. The water layer in this confined aquifer is in convective motion and can be considered as a low enthalphy geothermal system. Many of the routine uses to which geothermal waters are put, such as space heating and soil warming, are not applicable in Brazil mainly because of the favourable climatic conditions. Conversion of this geothermal energy into electrical energy is also unlikely to be economical. Hence we do not consider the Parana Basin geothermal system as an independent ec9nomically exploitable energy resource. However, a few other applications are pointed out where geothermal waters can be used as a supplementary or supporting energy source in increasing the efficiency of economically viable systems utilizing hot waters. 相似文献
104.
The deep oil exploration drillings in Denmark have shown that especially the Danish Embayment contains low enthalpy geothermal resources associated with warm aquifers. The most promising reservoirs have been found in highly permeable Upper Triassic sand and sandstone beds, which cover at least 5000 km2 at depths of 2000–3000 m and at temperatures of 60–100°C. The porosity of the main reservoir is of 15–25%, and the permeability is presumed to be approximately 1 darcy (10–12 m2) or higher. A layer thickness of 30–60 m has been observed on a number of localities. Also the Middle Jurassic and the Lower Triassic contain reservoirs of interest. A major geothermal exploration work is planned with seismic investigations, drillings to depths of 2000–4000 m and probably establishment of pilot district heating plants. 相似文献
105.
Over the last 2 years, more than seven million fish and 16,000 birds have died from drought-induced disease and suspected poisoning at Stillwater Lakes, Nevada. Correspondence analysis of water samples taken in June and September 1986, from lakes and reservoirs near Stillwater Lakes and four background lakes/reservoirs (not associated with fauna disease and death), is attempted to investigate the correlation among sites associated with fauna deaths. This analysis identifies high correlation between some Stillwater Lakes sites and boron. A correlation between boron and arsenic is also identified. Leaching and transport of toxins to the Stillwater Lakes system is one hypothesis to explain the wildlife deaths. Other hypotheses include the direct introduction of toxins by groundwater associated with geothermal activity. A natural cause for the wildlife deaths is also suggested, a cause not associated with the introduction of toxins. 相似文献
106.
107.
热源、热储层(砂体厚度、孔隙度、渗透率)、地温场等是影响地热资源评价的重要因素。本文以渭河盆地西安凹陷-西安市延长石油西化小区为例,在收集前人资料的基础上,应用地层测温、测井、岩芯分析等资料,分析了研究区地温场特征、热储层特征及地热资源量,运用多种参数对热储层有利区进行了综合评定。研究结果表明延长石油西化小区属地热异常区,地温梯度为3.5℃/100 m;研究区张家坡组、蓝田灞河组砂泥岩互层发育,砂厚分布在40~140 m之间,平均孔隙度分布在15.68%~30.3%之间,蓝田灞河组砂层厚度、地层热量、含水量和总热量均高于三门组和张家坡组地层,地热开发条件最好;综合考虑砂体厚度、地层含水量、地温梯度、地温、热储层物性因素,认为西安凹陷延长石油西化小区地热开发应选择蓝田灞河组为主要目的层段,最优的地热开发方式应采用采灌平衡法进行地热开采,综合考虑研究区更宜选择中深层地埋管井下换热方式进行地热资源开发。 相似文献
108.
109.
武山温泉热流体主要赋存于F1、F2断裂交汇部位的碎裂状斑状花岗岩体中,热水水温56.2℃,富含锂、锶、氟、偏硅酸等多种微量元素,主要用于浴疗治病和保健。本文通过对温泉地热资源形成的地质背景分析,初步论证了地热田的热储和控热构造,评价了地热资源储量,并对温泉开发利用前景作了分析。 相似文献
110.
东营市城区馆陶组热储为新近系松散碎屑岩层状热储,目前地热资源开采量约95万m3/a,回灌是解决热储压力下降与地热尾水排放对环境造成不良影响的最佳措施,该文采用自然回灌试验方法探讨回灌条件下馆陶组热储的渗透性能,并与德州市城区馆陶组热储压力回灌试验成果进行了对比,对该热储的回灌性能进行了分析,为指导该区地热回灌提供了科学依据。 相似文献