Application of heat-flow techniques to geothermal energy exploration, Leach Hot Springs area, Grass Valley, Nevada

Residual aeromagnetic data of parts of Southeastern Nigerian sedimentary basin were reduced to the equator and subjected to magnetic vector inversion and spectral analysis. Average depths of source ensembles from spectral analysis were used to compute depth to magnetic tops (Z), base of the magnetic layer (Curie Point t Depth (CPD)), and estimate geothermal gradient and heat flow required for the evaluation of the geothermal resources of the study area. Results from spectral analysis showed depths to the top of the magnetic source ranging between 0.45 km and 1.90 km; centroid depths of 4 km - 7.87 km and CPD of between 6.15 km and 14.19 km. The CPD were used to estimate geothermal gradients which ranged from 20.3°C/km to 50.0°C/km 2 2 and corresponding heat flow values of 34.9 mW/m to 105 mW/m , utilizing an average thermal conductivity -1 -1 of 2.15 Wm k . Ezzagu (Ogboji), Amanator-Isu, Azuinyaba, Nkalagu, Amagunze, Nta-Nselle, Nnam, Akorfornor environs are situated within regions of high geothermal gradients (>38°C/Km) with models delineated beneath these regions using 3D Magnetic Vector Inversion, having dominant NW-SE and NE-SW trends at shallow and greater depths of <1km to >7 km bsl. Based on VES and 2D imaging models the geothermal system in Alok can be classified as Hot Dry Rock (HDR) type, which may likely have emanated from fracture systems. There is prospect for the development of geothermal energy in the study area. Keywords: Airborne Magnetics, Magnetic Vector Inversion, Geothermal Gradient, Heat Flow, Curie Point Depth, Geothermal Energy.

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Geochemical Characteristics of Hydrothermal Volatiles From Southeast China and Their Implications on the Tectonic Structure Controlling Heat Convection

Frontiers in Earth Science ◽

10.3389/feart.2021.786051 ◽

2021 ◽

Vol 9 ◽

Author(s):

Jiao Tian ◽

Yiman Li ◽

Xiaocheng Zhou ◽

Zhonghe Pang ◽

Liwu Li ◽

...

Keyword(s):

Heat Flow ◽

Hot Springs ◽

Volatile Component ◽

Geochemical Characteristics ◽

Chemical Compositions ◽

Adjacent Area ◽

Geothermal Area ◽

Tectonic Structure ◽

Southeast China ◽

Geothermal Fluids

Hot springs and igneous rocks are present widely in southeast China, influenced by the subduction of the Western Pacific and Philippine Sea Plates. This study reports on new data of chemical compositions and He–Ne–C isotopes for gas samples from representative hot springs and wells in the Guangdong and Fujian provinces to identify the origin of hydrothermal volatiles and provide insight into geothermal tectonic affinities. The primary hydrothermal volatile component from southeast China is atmospheric N2, with a volumetric percentage of 82.19%–98.29%. It indicates medium-low temperature geothermal systems where geothermal fluids suffered a shallow circulation in closed fracture systems. Low CO2 and CH4 contents and their depleted δ13C values confirmed the small number of deep-derived components in the study area. However, spatially discernible geochemical characteristics imply enhanced hydrothermal fluid convection in the adjacent area of the two provinces, including the Fengshun, Zhangzhou, Longyan, and Sanming geothermal fields. Specifically, the He–Ne isotopes from this area exhibit mantle He contribution of more than 10% and mantle heat flow accounts for more than half of the total heat flow. Moreover, according to the thermal background calculations, the highest heat flow value of 77.7 mW/m2 is indicated for the Zhangzhou geothermal area and the lowest value of 54.7 mW/m2 is indicated for the Maoming geothermal area. Given the epicenter distributions and the corresponding earthquake magnitudes, the NE-trending faults are heat-control tectonic structures and their intersections with the NW-trending faults provided expedite channels for geothermal fluids rising to the surface. Therefore, the preferred development potential of geothermal resources can be expected in the adjacent area of the two provinces where two sets of active faults crossed. This study provides critical information on understanding the geothermal distribution controlled by the tectonic structure in southeast China.

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Geothermal energy prospectivity of the Torrens Hinge Zone: evidence from new heat flow data

Exploration Geophysics ◽

10.1071/eg09022 ◽

2009 ◽

Vol 40 (3) ◽

pp. 288-300 ◽

Cited By ~ 5

Author(s):

Chris Matthews

Keyword(s):

Heat Flow ◽

Geothermal Energy ◽

Flow Data ◽

Hinge Zone

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Thermal conditions for geothermal energy exploitation in the Transcarpathian depression and surrounding units

Contributions to Geophysics and Geodesy ◽

10.1515/congeo-2016-0003 ◽

2016 ◽

Vol 46 (1) ◽

pp. 33-49 ◽

Cited By ~ 2

Author(s):

Dušan Majcin ◽

Roman Kutas ◽

Dušan Bilčík ◽

Vladimír Bezák ◽

Ignat Korchagin

Keyword(s):

Temperature Field ◽

Heat Flow ◽

Field Distribution ◽

Geothermal Energy ◽

Thermal Conditions ◽

Flow Density ◽

Heat Flow Density ◽

Temperature Field Distribution ◽

Energy Exploitation

Abstract The contribution presents the results acquired both by direct cognitive geothermic methods and by modelling approaches of the lithosphere thermal state in the region of the Transcarpathian depression and surrounding units. The activities were aimed at the determination of the temperature field distribution and heat flow density distribution in the upper parts of the Earth’s crust within the studied area. Primary new terrestrial heat flow density map was constructed from values determined for boreholes, from their interpretations and from newest outcomes of geothermal modelling methods based on steady-state and transient approaches, and also from other recently gained geophysical and geological knowledge. Thereafter we constructed the maps of temperature field distribution for selected depth levels of up to 5000 m below the surface. For the construction we have used measured borehole temperature data, the interpolation and extrapolation methods, and the modelling results of the refraction effects and of the influences of source type anomalies. New maps and other geothermic data served for the determination of depths with rock temperatures suitable for energy utilization namely production of electric energy minimally by the binary cycles. Consequently the thermal conditions were used to identify the most perspective areas for geothermal energy exploitation in the region under study.

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Heat flow in the Garibaldi volcanic belt, a possible Canadian geothermal energy resource area

Canadian Journal of Earth Sciences ◽

10.1139/e81-028 ◽

1981 ◽

Vol 18 (2) ◽

pp. 366-375 ◽

Cited By ~ 15

Author(s):

J. F. Lewis ◽

Alan M. Jessop

Keyword(s):

Heat Flow ◽

Geothermal Energy ◽

Thermal Conduction ◽

Energy Resource ◽

Volcanic Belt ◽

Geothermal Reservoir ◽

Energy Potential ◽

Geothermal Heat ◽

Groundwater Movement ◽

Uplift And Erosion

The geothermal heat flow has been determined in four boreholes drilled within the area of the Garibaldi volcanic belt of southwestern British Columbia, Canada. The program was designed to investigate a suspected geothermal reservoir and the surrounding area as part of a continuing program of the Canadian Federal Government to assess the geothermal energy potential in western Canada.The measurements, after application of corrections for sediment diffraction, topography, Pleistocene thermal history, and uplift and erosion, fall into two distinct catagories. Three of the measurements, at distances greater than 10 km from Mt. Meager, have a mean of 79 mW m−2 with a standard deviation of 10 mW m−2, and the single measurement near Mt. Meager indicates a heat flux of 132 mW m−2. All these measurements are suspect to a certain degree because of groundwater movement at and around the measurement sites. The three distant observations are similar to others in the Cordilleran thermal zone, whereas the result at Mt. Meager appears to be anomalous. This pattern suggests that near the Mt. Meager area heat is being transported by means other than simple thermal conduction, consistent with other studies that indicate the presence of a geothermal reservoir of unknown size.

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Heat flow near Kyle Hot Springs, Buena Vista Valley, Nevada

10.2172/7300767 ◽

1976 ◽

Author(s):

J.H. Sass ◽

H.A. Wollenberg ◽

D.E. di Somma ◽

J.P. Ziagos

Keyword(s):

Heat Flow ◽

Hot Springs ◽

Buena Vista

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Analisa Geokimia Fluida Manifestasi Permukaan di Daerah Panas Bumi Lahendong

Fullerene Journal of Chemistry ◽

10.37033/fjc.v5i1.148 ◽

2020 ◽

Vol 5 (1) ◽

pp. 45

Author(s):

Jeferson Polii ◽

Alfrie Musa Rampengan

Keyword(s):

Sulfuric Acid ◽

Geothermal Energy ◽

Hot Springs ◽

Volcanic Rocks ◽

North Sulawesi ◽

Hot Air ◽

Geothermal Potential ◽

Acid Type ◽

The Village ◽

Plate Subduction

Geothermal energy depends on volcanic regions or plate subduction. Indonesia has geothermal potential due to the meeting of 3 (three) large plates. North Sulawesi is one of the areas located in the ring of fire. Some areas in the Minahasa Regency, North Sulawesi province, were targeted for research because they have manifestations of geothermal such as hot pools, steaming ground, mud pools, and other manifestations. The research location is divided into 3 (three) locations around the Lahendong geothermal area, namely the Lahendong pine forest, the Toraget hot air area, and the hot springs in the village of Totolan. The results of sample and ploting tests in ternary diagrams show that all three geothermal manifestations have sulfuric acid type fluids. This type of geothermal fluid has a high SO4 content, while HCO3 and Cl values are low. Hot springs that have a type of sulfuric acid occur in active volcanic regions. This is supported by the lithology of three areas of manifestation which are composed of basalt resulting from volcanic rocks.

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Estimation of Geothermal Gradient and Heat Flow for Determination of Geothermal Energy Sources in Monguno Area of Northeastern Nigeria

Journal of Geography Environment and Earth Science International ◽

10.9734/jgeesi/2019/v20i130095 ◽

2019 ◽

pp. 1-8

Author(s):

B. C. Udochukwu ◽

M. Akiishi ◽

A. A. Tyovenda

Keyword(s):

Heat Flow ◽

Curie Point ◽

Geothermal Energy ◽

Geothermal Gradient ◽

High Heat ◽

Curie Point Depth ◽

The South ◽

Geothermal Resources ◽

North East ◽

Curie Depth

The aeromagnetic data of Monguno area northeastern Nigeria have been used to estimate Curie point depth, geothermal gradients and heat flow using spectral analysis. These geothermal parameters were subsequently employed to identify areas of geothermal resources. First order polynomial fitting was applied in Regional-residual separation. The Curie point depth obtained in this area ranges from 10.318 to 24.476 km with an average of 13.387 km, the geothermal gradient of the area varies from 23.697 to 56.212°C /km, with an average of 46.195°C /km, while the heat flow ranges from 59.242 to 136.176 mWm-2, with an average value of about 112.364 mWm-2. It was also observed that the deepest Curie depth in the area is identified in the south, while the shallow depth is located in the northeast and spread toward the southwest. On the other hand, the highest geothermal gradient in the area is identified in the northern part of Moguno, while in the south, the lowest, geothermal gradient is located. The highest heat flow in the area is seen in the south-west and north-east, while the lowest heat flow is observed in the south. The high heat flow and geothermal gradient in the area show that geothermal energy could be found in Monguno region of the northeastern Nigeria.

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