共查询到20条相似文献，搜索用时 31 毫秒
1.
Exploring for Geothermal Resources with Electromagnetic Methods 总被引：5，自引：3，他引：2
Gerard Muñoz 《Surveys in Geophysics》2014,35(1):101-122
Electrical conductivity of the subsurface is known to be a crucial parameter for the characterization of geothermal settings. Geothermal systems, composed by a system of faults and/or fractures filled with conducting geothermal fluids and altered rocks, are ideal targets for electromagnetic (EM) methods, which have become the industry standard for exploration of geothermal systems. This review paper presents an update of the state-of-the-art geothermal exploration using EM methods. Several examples of high-enthalpy geothermal systems as well as non-volcanic systems are presented showing the successful application of EM for geothermal exploration but at the same time highlighting the importance of the development of conceptual models in order to avoid falling into interpretation pitfalls. The integration of independent data is key in order to obtain a better understanding of the geothermal system as a whole, which is the ultimate goal of exploration. 相似文献
2.
Hydrothermal systems in regions of high relief may not have obvious thermal features indicative of their central upflow zone at depth. Investigation of such areas for geothermal energy production in the Philippines has, however, encountered relatively large ( > 10,000 m2) areas of volumetrically significant but diffuse, cold-gas emission and associated intense argillic alteration. These features are likely to be best developed above, or close to, hydrothermal upflow zones. The identification of such features is important for interpreting the hydrology of active geothermal systems in the course of exploration for power development, or when interpreting the paleohydrology of fossil geothermal systems which host epithermal mineral deposits. Such zones of argillic alteration are likely to be barren of precious metals or other elements (except mercury) which are commonly used as pathfinders for precious-metal deposits, but are indicative of subsurface processes significant in ore genesis.It is proposed that the term “kaipohan” be used for such features. Their existence depends on the presence of either a low-permeability geologic formation or where a suitable relationship exists between the hydrology of the deep geothermal reservoir and that of the shallow groundwater system. Such a situation occurs in steep terrain, where much of the area supplying meteoric recharge to the geothermal system is at a lower elevation than the area overlying the centre of the system, and where there is a high annual rainfall. These conditions are typical of andesitic stratovolcanoes in tropical or subtropical island arcs. 相似文献
3.
地热地球物理勘探新进展 总被引：2，自引：0，他引：2
地热作为一种清洁能源具有巨大的开发潜力,将在我国的经济发展中起到巨大的作用.在传统的热水型地热开发的基础上,国际上非常重视热干岩(Enhanced Geothermal)型地热的勘探开发.在这两类地热勘查和开发中,地球物理方法具有非常重要的作用.本文从地热系统的目标体岩石的地球物理性质出发,分析岩石的地球物理性质与温度、压力和含水量等影响因素的关系.例如随着温度的升高,岩石会出现去磁、电阻率降低、密度降低、弹性波速度也现明显降低等现象.进而分析地球物理方法应用到具体的地热勘查地质-地球物理异常模型.结合国际上21世纪以后的新方法技术,分析了重磁、电、地震方法在利用由于岩石温度的升高而出现的特殊地球物理现象,并应用于地热勘探.通过国内外实例介绍了各种地球物理勘探方法在地热勘查中成功应用,为进一步提高我国地热勘查水平,提供一些参考. 相似文献
4.
5.
Geophysical greenfield exploration in the permo‐carboniferous Saar–Nahe basin—The Wiesbaden Geothermal Project,Germany 
下载免费PDF全文
下载免费PDF全文 Hagen Deckert Wolfgang Bauer Steffen Abe Franklin G. Horowitz Ulrich Schneider 《Geophysical Prospecting》2018,66(Z1):144-160
Structurally bound upwelling and outflowing hot fluids in the city of Wiesbaden suggest an interesting geothermal potential at the northern margin of the permo‐carboniferous Saar–Nahe basin, Germany. The Saar–Nahe basin in the Wiesbaden area was previously not a target for intensive geophysical prospecting of the deep underground. We present an exploration concept to investigate potential geothermal reservoirs near Wiesbaden for heat and power production. The acquired geophysical exploration data give new insights into the local geometry and internal structure of the Saar–Nahe basin. The exploration combines a wide range of methods, including the analysis of data, a dense grid gravity survey, as well as two‐dimensional and three‐dimensional seismic surveys. The resulting data, which for the first time reveal the deep structure of the Mainz and Saar–Nahe basins near Wiesbaden down to a depth of c. 4,000 m, show that the Saar–Nahe basin is strongly segmented and contains deep‐reaching active faults. Combining these information with numerical models of the stresses in the fault system and of the temperature distribution in the exploration area, a promising drilling target has been identified, which promise high permeability at a low risk of induced or triggered seismicity. 相似文献
6.
Wang Ji-Yang Chen Mo-Xiang Wang Ji-An Deng Xiao Wang Jun Shen Hsien-Chieh Hsiung Liang-Ping Yan Shu-Zhen Fan Zhi-Cheng Liu Xiu-Wen Huang Ge-Shan Zhang Wen-Ren Shao Hai-Hui Zhang Rong-Yan 《Journal of Volcanology and Geothermal Research》1981,9(1):57-76
Geothermal studies have been conducted in China continuously since the end of the 1950's with renewed activity since 1970. Three areas of research are defined: (1) fundamental theoretical research on geothermics, including subsurface temperatures, terrestrial heat flow and geothermal modeling; (2) exploration for geothermal resources and exploitation of geothermal energy; and (3) geothermal studies in mines.Regional geothermal studies have been conducted recently in North China and more than 2000 values of subsurface temperature have been obtained. Temperatures at a depth of 300 m generally range from 20 to 25°C with geothermal gradients from 20 to 40°C/km. These values are regarded as an average for the region with anomalies related to geological factors.To date, 22 reliable heat flow data from 17 sites have been obtained in North China and the data have been categorized according to fault block tectonics. The average heat flow value at 16 sites in the north is 1.3 HFU, varying from 0.7 to 1.8 HFU. It is apparent that the North China fault block is characterized by a relatively high heat flow with wide variations in magnitude compared to the mean value for similar tectonic units in other parts of the world. It is suggested that although the North China fault block can be traced back to the Archaean, the tectonic activity has been strengthening since the Mesozoic resulting in so-called “reactivation of platform” with large-scale faulting and magmatism.Geothermal resources in China are extensive; more than 2000 hot springs have been found and there are other manifestations including geysers, hydrothermal explosions, hydrothermal steam, fumaroles, high-temperature fountains, boiling springs, pools of boiling mud, etc. In addition, there are many Meso-Cenozoic sedimentary basins with widespread aquifers containing geothermal water resources in abundance. The extensive exploration and exploitation of these geothermal resources began early in the 1970's. Since then several experimental power stations using thermal water have been set up in Fengshun (Fungshun), 相似文献
7.
The Aluto-Langano geothermal field is located in the central southern portion of Ethiopia within the Ethiopian Rift Valley.
The gravity of the area was surveyed in an attempt to delineate the subsurface structure and to better understand the relationship
between the geothermal systems and the subsurface structure. The gravity data were analyzed using integrated gradient interpretation
techniques, such as the Horizontal Gradient (HG), Source Edge Detection (SED), and Euler Deconvolution (ED) methods. These
techniques detected many faults that were compared with the mapped faults in the surface geology. The results of the present
study will lead to an improved understanding of the geothermal system in the study area and aid the future geothermal exploration
of the area. 相似文献
8.
J.P. Cull 《Journal of Volcanology and Geothermal Research》1981,9(1):77-85
Secular and long-term periodic changes in surface temperature cause perturbations to the geothermal gradient which may be significant to depths of at least 1000 m, and major corrections are required to determine absolute values of heat flow from the Earth's interior. However, detailed climatic models remain contentious and estimates of error in geothermal gradients differ widely. Consequently, regions of anomalous heat flow which could contain geothermal resources may be more easily resolved by measuring relative values at a standard depth (e.g. 100 m) so that all data are subject to similar corrections.Regional heat flow data obtained in existing deep holes show reasonable correlation with values determined at shallow depth. Hence geothermal resources of low enthalpy can be characterised by extrapolating temperatures from relative heat flow data readily obtained from shallow boreholes. Regional control can be provided by casing deep boreholes drilled for other purposes.For routine geothermal exploration, borehole temperatures can be measured using gradient probes with fixed sensor separation (e.g. 5 m), allowing very accurate determinations of the geothermal gradient at a single depth. Values of relative heat flow can then be obtained after determining the thermal resistivity of the corresponding core interval. Sampling errors can be minimised by multiple determinations of thermal conductivity over the complete interval. 相似文献
9.
10.
中国地球物理学会勘探地球物理专业委员会水资源工程物探学组 《地球物理学报》1997,40(Z1):369-378
回顾了我国水文、工程和环境物探近50年的历史，简介了我国水文、工程、环境物探发展的四个阶段．重点论述了我国能源、交通和城市工程物探在电力、铁路、水利建设以及海洋平台工程建设等领域内取得的重大成就；介绍了水资源和地热物探在农业、工业和城市建设中的重要贡献；分析了我国水文、工程、环境物探的技术进步；最后提出了发展方向． 相似文献
11.
Geothermal resource assessment is the broadly based appraisal of the quantities of heat that might be extracted from the earth and used economically at some reasonable future time. In the United States, the Geological Survey is responsible for preparing geothermal assessments based on the best available data and interpretations. Updates are required every few years owing to increasing knowledge, enlarging data base, improving technology, and changing economics. Because geothermal understanding is incomplete and rapidly evolving, the USGS complements its assessments with a broad program of geothermal research that includes (1) study of geothermal processes on crustal and local scales, (2) regional evaluations, (3) intensive study of type systems before and during exploitation (4) improvement of exploration techniques, and (5) investigation of geoenvironmental constraints. 相似文献
12.
Electromagnetic sounding of geothermal zones 总被引：1，自引：0，他引：1
Electromagnetic (EM) data provide a substantial contribution to the geophysical mapping and monitoring of geothermal reservoirs. This paper presents an up-to-date picture of the achievements of EM methods for geothermal exploration as they have emerged over the last few years. It has been proved that EM sounding of geothermal zones and distant monitoring macro-parameters of the reservoirs, fluid-filled faults and other elements of the geothermal system are possible provided that modern 3-D inversion is used along with techniques that reduce the effects of industrial and geological noise. In addition, geological and petrophysical data also need to be included in the analysis. 相似文献
13.
CSAMT法是一种强有力的地球物理勘探手段,具有测量迅速、探测深度大、信噪比高等优点,已被广泛应用于金属矿、油气田、地下水、以及地热田的勘探中.在CSAMT勘探资料解释方面,传统的二维电阻率断面很难清晰、直观地揭示3D(三维)地电结构的分布特征,为此应加强3D可视化应用技术的研究.本文详细的介绍了3D可视化的建模过程,将3D构造的建模分为空间曲面剖分、空间曲面拟合插值、空间曲面拓扑关系生成、3D结构网格剖分、属性建模等过程.并以一个CSAMT勘探实例,展现出3D可视化方法技术的突出优势.三维可视化可以多角度、多层面展现地下3D电性结构的分布特征,使我们更加清晰、直观地了解3D地质体的空间范围与几何形态. 相似文献
14.
L. Guglielmetti F. Poletto P. Corubolo A. Bitri C. Dezayes B.M. Farina F. Martin F. Meneghini A. Moscariello C. Nawratil de Bono A. Schleifer 《Geophysical Prospecting》2020,68(4):1139-1153
This paper deals with the design, acquisition and processing of vertical seismic profiling data collected in 2016 at the directional Thônex-01 geothermal well, drilled in 1993 in the Geneva Canton (Switzerland). The aim of the study was to obtain additional information from existing-abandoned well for downhole geophysical characterization of potential geothermal reservoirs in the Geneva area. The main results obtained by this study allowed an improved subsurface image by multi-offset acquisitions near and around the deviated well. Specifically we were able to (1) improve the velocity model of the Geneva Basin, which, at present, is only constrained by one unique deep exploration well, located at the south-west of the basin, far away from the study area; (2) image the transition between the Tertiary Molasse siliciclastic sediments and the Mesozoic carbonates; (3) define an acquisition strategy for future vertical seismic profiling surveys in support of the geothermal exploration campaigns in the area. This study has demonstrated the value of vertical seismic profiling method for the refinement of the subsurface geology at local scale, and its usefulness to assist the planning of second well associated with geothermal doublets. 相似文献
15.
查干凹陷是中国内蒙古银根-额济纳旗盆地中最具有勘探潜力的凹陷.为了揭示其构造-热演化历史,本文利用35个磷灰石裂变径迹和119个镜质体反射率数据,采用耦合反演的方法恢复了查干凹陷白垩纪以来的热历史.结果显示查干凹陷白垩系具有高的古地温梯度,并且查干凹陷经历了地温梯度快速增加阶段(K1b-K1s),地温梯度高峰阶段(K1y),高地温延续阶段(K2w)和热沉降阶段(Cz)四个构造-热演化阶段.此外,基于热史恢复结果,正演获得查干凹陷高的古地温梯度有利于烃源岩成熟生烃,早白垩世的高古地温梯度控制着该地区的烃源岩有机质的热演化.本文的研究成果可以为下一步油气资源评价和勘探决策提供基础依据. 相似文献
16.
Jacques Demange Pierre Chovelon Pascal Puvilland 《Journal of Volcanology and Geothermal Research》1989,36(1-3)
A programme of geothermal exploration on Réunion Island resulted in the siting of an exploration geothermal borehole in Salazie Cirque. The borehole attained a depth of 2108 m and encountered temperatures of 192 ± 8°C; no aquifer was found.The geological information obtained made it possible to propose a stratigraphy for the deep underlying rocks beneath the Salazie Cirque on the Piton des Neiges and thus to interpret the events that followed the emergence of the island. A large gabbroic mass was intersected and found to comprise several successive intrusions, the principal one of which is continuously zoned from melagabbro to monzonite. Modeling of geophysical data on the drillhole results enabled the distribution of the different geological units to be interpreted.A geothermal model is proposed taking into account the dynamic evolution of the hydrothermal processes that preceded and accompanied emplacement of the gabbro responsible for the geothermal anomaly underlying the three cirques that sculpt the flanks of the Piton des Neiges. 相似文献
17.
本文使用天然源超低频电磁探测仪对北京大学校园内两口地热井进行了超低频电磁探测试验,获得了1号地热井（京热119号井）连续五天、每天四个时刻的天然源超低频电磁探测数据以及2号地热井（京热168号井）单天的天然源超低频探测的数据.基于所获得的数据,开展了地热井的天然源超低频探测影响因素的研究,这些因素主要包括：天然源超低频电磁场和观测时间的关系、探头摆放方向与接收工频谐波干扰关系以及天气状况对观测数据质量的影响等.研究表明：(1)天然源超低频电磁探测信号存在明显的日夜交替变化,其中相对振幅-频率曲线在不同日期、同一邻近时刻总体的包络线具有较好的重复性和一定的稳定性;(2)工频谐波干扰场方向是影响因素之一,当仪器探头长轴方向与工频谐波干扰场的等效主轴方向平行时噪声影响最小;(3)雨天环境会对天然场源超低频信号中的高频部分造成较大影响. 相似文献
18.
19.
Geothermal electric power plant with a capacity of 10 mw has been now constructed by the Kyushu Electric Power Co. Ltd. at Otake, northern part of the Kyushu Island. Resistivity exploration, one of geophysical prospecting applied to this field in order to investigate the subsurface structure accompanied with natural steams, indicated low resistivity layer corresponding to altered zone of andesite due to hydrothermal agents. For the rapid interpretation of resistivity sounding curves, a method of calculating the standard curve for the multiple layered earth is developed in the utilization of an electronic digital computer. Some examples to show the application of this method are given, and tinally the result is described of resistivity measurement at Otake geothermal area. 相似文献
20.
In total 77 direct current resistivity soundings were carried out during a geothermal exploration survey of the Genisea, NE Greece, geothermal field. The data revealed a high electrical conductivity zone at the center of the investigated area and suggested that an anomalous heat source lay beneath the study area. This was confirmed by subsequent drilling data. Temperature measurements, from 11 boreholes, were used for the construction of isotherms that correlated very closely with the geoelectric data. 相似文献