HEAT FLOW AND GEOTHERMAL GRADIENT STUDIES IN THE ALBERTA BASIN AN ESSENTIAL PART OF GEOTHERMAL POTENTIAL EVALUATION

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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Audiomagnetotelluric survey at the Bañitos-Gollete geothermal area, main Andes Cordillera of San Juan, Argentina.

Geologica Acta ◽

10.1344/geologicaacta2019.17.8 ◽

2019 ◽

Author(s):

H. BARCELONA ◽

G. PERI ◽

D. WINOCUR ◽

A. FAVETTO

Keyword(s):

Geothermal Gradient ◽

Geothermal Field ◽

Flow Path ◽

Fault System ◽

Conductive Heat ◽

Exploration Process ◽

Tectonic Environment ◽

Geothermal Potential ◽

Geologic Setting ◽

Andes Cordillera

The present research explores the Bañitos-Gollete geothermal field located in the Frontal Andes Cordillera over the Pampean flat-slab. We carried out an audiomagnetotelluric survey in order to define the underground geoelectrical structure and to understand the link between the geothermal fluid flow path and the main geological structures. 2-D audiomagnetotelluric models suggest that the deep-rooted N-S fault system controls the geothermal flow path. We propose a conductive heat-driven system, taking into consideration the geologic setting and the supposed low geothermal gradient of this tectonic environment. The mature Na-Cl waters from Gollete and an estimated reservoir temperature of ~140ºC are consistent with this conceptual model. Further investigations are required to assess the geothermal potential of the study area, and the present work likely represents only the first but necessary step in the exploration process.

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Relationship among terrestrial heat flow, thermal conductivity, and geothermal gradient

Journal of Geophysical Research Atmospheres ◽

10.1029/jb075i011p01985 ◽

1970 ◽

Vol 75 (11) ◽

pp. 1985-1991 ◽

Cited By ~ 15

Author(s):

Ki-Iti Horai ◽

Amos Nur

Keyword(s):

Thermal Conductivity ◽

Heat Flow ◽

Geothermal Gradient ◽

Terrestrial Heat Flow

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Heat Flow and Geothermal Potential in the South-Central United States

Natural Resources Research ◽

10.1007/s11053-008-9081-x ◽

2008 ◽

Vol 17 (4) ◽

pp. 227-243 ◽

Cited By ~ 5

Author(s):

Petru T. Negraru ◽

David D. Blackwell ◽

Kamil Erkan

Keyword(s):

United States ◽

Heat Flow ◽

The South ◽

South Central ◽

Geothermal Potential ◽

Central United States

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Inversion of bottom‐hole temperature data: The Pineview field, Utah‐Wyoming thrust belt

Geophysics ◽

10.1190/1.1442504 ◽

1988 ◽

Vol 53 (5) ◽

pp. 707-720 ◽

Cited By ~ 23

Author(s):

Dave Deming ◽

David S. Chapman

Keyword(s):

Thermal Conductivity ◽

Temperature Field ◽

Heat Flow ◽

Random Noise ◽

Synthetic Data ◽

Element Model ◽

Geothermal Gradient ◽

Oil Field ◽

Conductive Heat ◽

Bottom Hole

The present day temperature field in a sedimentary basin is a constraint on the maturation of hydro‐carbons; this temperature field may be estimated by inverting corrected bottom‐hole temperature (BHT) data. Thirty‐two BHTs from the Pineview oil field are corrected for drilling disturbances by a Horner plot and inverted for the geothermal gradient in nine formations. Both least‐squares [Formula: see text] norm and uniform [Formula: see text] norm inversions are used; the [Formula: see text] norm is found to be more robust for the Pineview data. The inversion removes random error from the corrected BHT data by partitioning scatter between noise associated with the BHT measurement and correction processes and local variations in the geothermal gradient. Three‐hundred thermal‐conductivity and density measurements on drill cuttings are used, together with formation density logs, to estimate the in situ thermal conductivity of six of the nine formations. The thermal‐conductivity estimates are used in a finite‐element model to evaluate 2-D conductive heat refraction and, for a series of inversions of synthetic data, to assess the influence of systematic and random noise on the inversion results. A temperature‐anomaly map illustrates that a temperature field calculated by a forward application of the inversion results has less error than any single corrected BHT. Mean background heat flow at Pineview is found to be [Formula: see text] (±13 percent), but is locally higher [Formula: see text] due to heat refraction. The BHT inversion (1) is limited by systematic noise or model error, (2) achieves excellent resolution of a temperature field although resolution of individual formation gradients may be poor, and (3) generally cannot detect lateral variations in heat flow unless thermal‐conductivity structure is constrained.

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New insights on speleoseismology: The geothermal gradient and heat flow values in caves for the study of active faults

Quaternary International ◽

10.1016/j.quaint.2016.11.026 ◽

2017 ◽

Vol 451 ◽

pp. 165-175 ◽

Cited By ~ 2

Author(s):

R. Pérez-López ◽

S. Martín-Velázquez ◽

S. Sánchez-Moral ◽

M. Patyniak ◽

J. López-Gutiérrez ◽

...

Keyword(s):

Heat Flow ◽

Active Faults ◽

Geothermal Gradient

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A heat flow profile across the Sverdrup Basin, Canadian Arctic Islands

Geophysics ◽

10.1190/1.1442641 ◽

1989 ◽

Vol 54 (2) ◽

pp. 171-180 ◽

Cited By ~ 18

Author(s):

F. W. Jones ◽

J. A. Majorowicz ◽

A. F. Embry

Keyword(s):

Heat Flow ◽

Canadian Arctic ◽

Ground Surface ◽

Geothermal Gradient ◽

Flow Profile ◽

Heat Flows ◽

Boundary Temperature ◽

Sverdrup Basin ◽

Base Boundary ◽

Rock Analysis

An average geothermal gradient of 25 ± 5 mK/m and an average heat flow of [Formula: see text] have been determined for 16 out of 20 analyzed wells along a profile across the Sverdrup Basin in the Canadian Arctic. These estimates, based on deep bottom‐hole temperature (BHT) data from exploration wells and the permafrost base boundary temperature, together with assumed heat conductivities from net rock analysis, are surprisingly low and disagree with previously published results based on shallow data. The differences may be due to the dramatic changes in boundary temperature conditions from moderate subsea conditions to ground‐surface low temperatures as a result of marine regression. Because of these effects, it appears that deep BHT temperature data are valuable in providing information about the deep heat flow. The heat flows thus determined indicate that the basin has approached thermal equilibrium.

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