Estimation of Geothermal Gradient, Geothermal Heat Flux and Thermal Conductivity of Rocks in Western Niger Delta Using Well Log Data

AbstractOtan-Ile field, located in the transition zone Niger Delta, is characterized by complex structural deformation and faulting which lead to high uncertainties of reservoir properties. These high uncertainties greatly affect the exploration and development of the Otan-Ile field, and thus require proper characterization. Reservoir characterization requires integration of different data such as seismic and well log data, which are used to develop proper reservoir model. Therefore, the objective of this study is to characterize the reservoir sand bodies across the Otan-Ile field and to evaluate the petrophysical parameters using 3-dimension seismic and well log data from four wells. Reservoir sands were delineated using combination of resistivity and gamma ray logs. The estimation of reservoir properties, such as gross thickness, net thickness, volume of shale, porosity, water saturation and hydrocarbon saturation, were done using standard equations. Two horizons (T and U) as well as major and minor faults were mapped across the ‘Otan-Ile’ field. The results show that the average net thickness, volume of shale, porosity, hydrocarbon saturation and permeability across the field are 28.19 m, 15%, 37%, 71% and 26,740.24 md respectively. Two major faults (F1 and F5) dipping in northeastern and northwestern direction were identified. The horizons were characterized by structural closures which can accommodate hydrocarbon were identified. Amplitude maps superimposed on depth-structure map also validate the hydrocarbon potential of the closures on it. This study shows that the integration of 3D seismic and well log data with seismic attribute is a good tool for proper hydrocarbon reservoir characterization.

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Development of downhole geothermal heat flux and thermal conductivity transducers

10.2172/5815706 ◽

1978 ◽

Author(s):

H.F. Poppendiek ◽

D.J. Connelly ◽

A.J. Sellers ◽

C.M. Sabin ◽

J.G. Dunbar

Keyword(s):

Thermal Conductivity ◽

Heat Flux ◽

Geothermal Heat

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Porosity and compaction trend in Okan field (Western Niger Delta) based on well log data.

Global Journal of Pure and Applied Sciences ◽

10.4314/gjpas.v7i1.16211 ◽

2001 ◽

Vol 7 (1) ◽

Cited By ~ 1

Author(s):

E U EGEH ◽

C S OKEREKE ◽

O O OLAGUNDOYE

Keyword(s):

Niger Delta ◽

Well Log ◽

Log Data

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Thermal refraction: implications for subglacial heat flux

Journal of Glaciology ◽

10.1017/jog.2021.38 ◽

2021 ◽

pp. 1-10

Author(s):

Simon Willcocks ◽

Derrick Hasterok ◽

Samuel Jennings

Keyword(s):

Thermal Conductivity ◽

Heat Flux ◽

Small Scale ◽

Geothermal Heat ◽

Temperature Anomalies ◽

Bed Topography ◽

Subglacial Topography ◽

State Models ◽

Typical Range ◽

Conductivity Contrast

Abstract In this study, we explore small-scale (~1 to 20 km) thermal-refractive effects on basal geothermal heat flux (BGHF) at subglacial boundaries resulting from lateral thermal conductivity contrasts associated with subglacial topography and geologic contacts. We construct a series of two-dimensional, conductive, steady-state models that exclude many of the complexities of ice sheets in order to demonstrate the effect of thermal refraction. We show that heat can preferentially flow into or around a subglacial valley depending on the thermal conductivity contrast with underlying bedrock, with anomalies of local BGHF at the ice–bedrock interface between 80 and 120% of regional BGHF and temperature anomalies on the order of ±15% for the typical range of bedrock conductivities. In the absence of bed topography, subglacial contacts can produce significant heat flux and temperature anomalies that are locally extensive (>10 km). Thermal refraction can result in either an increase or decrease in the likelihood of melting and ice-sheet stability depending on the conductivity contrast and bed topography. While our models exclude many of the physical complexities of ice behavior, they illustrate the need to include refractive effects created by realistic geology into future glacial models to improve the prediction of subglacial melting and ice viscosity.

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