Curie Point Depth Research Articles

Curie point Depth and Heat Flow Analyses over Part of Bida Basin, North Central Nigeria using Aeromagnetic Data

This study attempt to estimate the Curie point depth (CPD) and heat flow using high resolution aeromagnetic data over part of Bida basin bounded with longitude 5o00’E – 6o30’E and Latitude 8o30’N – 9o30’N with an estimated total area of 18,150 km2. We subjected the total magnetic intensity field of the study area to regional/residual separation using polynomial fitting. We divided the residual map into sixteen overlapping spectral blocks. We obtained centroid depths (Zo) and depth to top of basement (Zt)got from the plot of log of power spectrum against wave number; the centroid depth ranges from 6.61 km to 20.30 km while the depth to top of basement ranges from 1.59 km to 6.38 km. input parameter to calculate the curie depth (Zo). The CPD range from 10.88 km to 35.51 km with an average value of 23.22km. The CPD is deeper at the centre of the southern and eastern part of the study area which correspond to part of Pategi and part of Baro; and shallow at the northeastern and Northwestern part of the study area correspond to part of Mokwa and part of Bida. The geothermal gradients for the sixteen blocks range from 16.33 oCkm-1 at the centre of the southern region of the area to 53.30 oCkm-1 at the northeastern and north western region of the study area with an average of 28.98 oCkm-1. While the heat flow to range from 40.99 mWm-1 to 133.80 mWm-1 with an average value of 76.19 mWm-2. It can therefore be deduced from this study that the Southeastern, southwestern, and the northwestern part of the study area might be a good indicator of geothermal energy potential with minimum CPD, maximum geothermal gradient and heat flow since demagnetized rocks confirm a hot rock quantity in the crust that can be harnessed for geothermal energy exploitation.

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

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.

Assessment of Geothermal Potentials In Some Parts of Upper Benue Trough Northeast Nigeria Using Aeromagnetic Data

The assessment of geothermal potentials over part of the upper Benue trough corresponding to Kaltungo, Guyok, Lau and Dong areas, North Eastern Nigeria using spectral depth analysis of aeromagnetic data has been carried out. The study area is bounded by latitudes 9o00’N and 10o00’N and longitudes 11o00’E and 12o00’E. This research work is necessitated by the need for renewable and alternative sources of energy for use in Nigeria. Regional/residual separation was carried out on the total magnetic field using polynomial fitting method of order one. The residual map was divided into nine overlapping blocks for the spectral analysis. The centroid depths and depth to top of basement were obtained from the plot of log of power spectrum against wavenumber. These two parameters were used to estimate the Curie point depth using , where and are Curie depth, centroid depth and depth to top of basement respectively. The results from the spectral analysis suggested that in the parts of the Upper Benue trough, the basement is deepest at the south western portion towards the Lau area and varies between 0.55 and 3.8 km, while the centroid depth varies from 7.26 to 18.00 km. From the same portion of the trough, the Curie-point depths vary between 12.43 and 33.91 km and the corresponding geothermal gradient and heat flow values varying from 17.10 to 46.66 0C/km with an average of 30.75 0C/km and 42.75 to 116.65 mW/m2 with an average of 75.91 mW/m2 respectively. The maximum heat flow is found around the south western portion of the study area (Lau). The entire study area with high heat flow values might probably be good sources for geothermal and thereby recommended for both geothermal exploration and exploitation.

An improved space domain algorithm for determining the 3-D structure of the magnetic basement

The paper presents an improved algorithm based on Bhaskara Rao and Ramesh Babu’s algorithm to invert magnetic anomalies of three-dimensional basement structures. The magnetic basement is approximated by an ensemble of juxtaposed vertical prisms whose bottom surface coincides with Curie surface with the known depth. The computer program operating with the proposed algorithm is built in Matlab environment. Test applications show that the proposed method can perform computations with fast and stable convergence rate where the results also coincide well with the actual model structure. The effectiveness of the method is demonstrated by inverting magnetic anomalies of the southeast part of Vietnam continental shelf. The calculated magnetic basement relief of the study area provides useful additional information for studies in the aim of dealing with the geological structure of the area.References Beiki M., 2010. 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Geothermal Energy Potential of the Chad Basin, North-Eastern Nigeria

In this research paper, the sub-surface heat flow of a part of the Chad Basin, in North eastern Nigerian was estimated using spectral analysis. This was obtained from twenty (20) digitized High Resolution Aeromagnetic (HRAM) data sheet covering the study area. Regional-residual separation using first order polynomial fitting method with three coefficients was carried out on the data map before the application of statistical spectral analysis. Result shows that the centroid depth varies between 9.39 km and 18.31 km. The depth to the Curie temperature isotherm varies between 15.14 km and 33.46 km below the mean sea level. It was also found that the Curie temperature isotherm within the basin is not a horizontal level surface but an undulating surface with geothermal gradients and heat flow ranging between 15.77 and 38.31°C/Km, and 39.41 and 95.77 mWm -2 respectively. Thus, the calculated average geothermal gradient and heat flow for this area are 23.39°C/Km and 58.47 mWm -2 respectively. Since average heat flow in thermally normal continental region is 60 and the values in excess of 80 mWm -2 – 100 mWm -2 are associated with anomalous geothermal conditions, hence the study area can generally be considered as a thermally normal region. But, the northeastern part of the study area with values in excess of 80 mWm -2 is recommended for further investigation Keywords: Geothermal energy, Spectral Analysis, Chad Basin. Curie point depth

Investigating edge detection, Curie point depth and heat flow using EMAG2 magnetic and EGM08 gravity data in northern part of Eastern Anatolia, Turkey

The edge detection, the Curie point depths (CPDs), and the heat flow in the northern part of Eastern Anatolia were examined using EMAG2 magnetic and EGM08 Bouguer gravity data. Edge detection methods are extensively employed to delineate the edges of sources using potential field data. In the study area, the tilt angle, total horizontal derivative, theta map, and 3D Euler deconvolution methods were used to delineate the subsurface geology and heterogeneity. The 3D Euler deconvolution method was carried out to determine the depth of the subsurface magnetic and gravity anomalies. The Euler depth solutions show that the depths range from 0 to 15 km for the Bouguer gravity anomalies, while the depths vary from 0 to 16 km for the magnetic anomalies. In this study area, the CPD values vary between 15.7 km and 18.6 km. For a thermal conductivity of 2.5 W m-1 K-1, the heat flow values were determined to be between 75 and 95 mW m-2. A plot of CPDs versus heat flow values revealed an exponential correlation between heat flow and CPD values. A good relationship was detected between the CPDs and the heat flow values.

Determination of Curie Point Depth, Heat Flow and Geothermal Gradient from High Resolution Aeromagnetic Data around Lamurde Area, Adamawa State, North-Eastern Nigeria

Analysis of high resolution of aeromagnetic data was carried out over Lamurde, Adamawa state north-eastern Nigeria to determine the Curie point depth (CPD), heat flow and geothermal gradient. The aeromagnetic data used for this work was obtained at Nigerian geological survey agency, the total magnetic intensity was processed to produce the residual magnetic map which was divided into 4 overlapping blocks, each block was subjected to spectral analyses to obtain depths to the top boundary and centroid, while depth to bottom of the magnetic sources was calculated using empirical formula. The depths values obtained were then used to assess the CPD, heat flow and geothermal gradient in the area. The result shows that the CPD varies between 9.62 and 10.92 km with an average of 10.45 k, the heat flow varies between 150.73 and 132.78 mWm−20⋅°C−1 with an average of 139.12 mWm−20⋅°C−1 and the geothermal gradient in the study area varies between 12.16 and 15.67 °C/km with an average of 13.39 °C/km. In view of the above results, the high heat flow may be responsible for maturation of hydrocarbon in Benue Trough as well as responsible for the lead Zinc Mineralization. Again by implication, Lamurde area can be a good area for geothermal reservoir exploration for an alternative source for power generation.

Fractal-Based Computation of Heat Source Depths and Temperatures for the Soutpansberg Basin, South Africa

The fractal-based approach was used for computing magnetic depths and temperatures for the Soutpansberg Basin in South Africa. The average depth to the top Zt and basement depth Zo for the Soutpansberg Basin were 4.36 ± 0.28 km, 10.43 ± 0.65 km, respectively. The average temperature at depth Zt was 184.69 ± 7.66 ºC. Magnetic source depths and basal temperatures that were in the Curie point range were determined, to be within 20.35 km to 21.68 km and 549.34 ºC to 585.24 ºC, respectively. Increasing the value of the fractal parameter β from 0 to 4, had an effect of retaining deeper depths and higher temperatures. The fractal parameter values of β > 3 retained Curie point depths and temperatures that indicated basal rock types with an igneous predisposition. The fractal-based approach proved to be an improved technique as compared to the conventional centroid method.

Geothermal Energy Reconnaissance of Southeastern Nigeria from Analysis of Aeromagnetic and Gravity Data

Given the daunting energy challenges currently bedeviling Nigeria, with demand for electrical power exceeding availability, alternative energy sources (preferentially renewable) are vigorously considered. This is the first study to examine geothermal energy prospects in southeastern Nigeria with the ultimate aim of locating and mapping regions of shallow Curie point depths (CPDs), crustal thickness, and geologic structures supportive of a geothermal system. We estimated CPD using the spectral analysis technique on magnetic field anomalies. Gravity anomalies were subjected to a series of procedures to assess geological structures. Result reveals deeper CPDs within central and southern regions of Okposi, Afikpo and Biase towns in an approximate range of 18.4 to 19.3 km. Shallow CPDs (9.8–17.4 km) have also been obtained within Obubra and Abakaliki regions. Estimated crustal thickness (Moho) ranges between 26.5 and 35.8 km. Part of the region with shallow CPD correlates with regions of shallow Moho depths, particularly in Abakaliki, and deeper Moho depths coincide with deeper CPD estimates at the Afikpo location. The estimated geothermal gradient and heat flow values range between 29.0 and 45.0 oC and 52.2–101.5 mW/m2, respectively, and fall within values evaluated from deep wells drilled for oil exploration within the adjoining Anambra Basin region. This study recommends the regions with shallow depths for possible geothermal power plant location. Gravity data evaluations also reveal significant subsurface intrusions within Ugbodo, Obubra and Abakaliki locations. Overall, this study is a step forward toward a better evaluation of the geothermal energy resources potential of southeastern Nigeria.

The effects of anisotropy of marine magnetic anomalies on the Curie point depth estimates from spectral analysis

Azimuthally averaged power spectra are widely used in the Curie point depth (CPD) estimation with the implicit assumption that the magnetization distribution is random and uncorrelated. However, the marine magnetic anomalies are caused by bands of normal and reverse magnetization and show obvious trends. To investigate the effects of the anisotropy of marine magnetic anomalies on the CPD estimates, we develop 3D fractal striped magnetization models to produce lineated marine magnetic anomalies for the first time. We analyze the spectra anisotropy of the lineated magnetic anomalies of the synthetic fractal striped magnetization models and investigate its effects on the CPD estimates. The synthetic models and actual data show that the spectra of the lineated marine magnetic anomalies are directionally anisotropic. The amplitude response is strong and the slope of the logarithmic spectrum is large in a direction perpendicular to the stripes of magnetic anomalies, whereas the amplitude response is weak and the slope of the logarithmic spectrum is small in a direction parallel to the stripes of magnetic anomalies. The depth estimates in the perpendicular direction are close to the actual values, whereas the depths estimates in the parallel direction are significantly lower than the actual values. The actual marine magnetic anomalies of the South China Sea exhibit an anisotropic power spectrum that is consistent with the spectral anisotropy of magnetic anomalies of the synthetic fractal striped magnetization models.

Estimation of Curie-point depths, geothermal gradients and near-surface heat flow from spectral analysis of aeromagnetic data in the Loum – Minta area (Centre-East Cameroon)

The current study deals with an estimate the Curie point depth, Heat flow and geothermal gradient from spectral analysis of aeromagnetic data in the Loum – Minta area, Centre-East Cameroun. Aeromagnetic data reduce to equator was divided into 5 blocks. All of the blocks overlapped with adjoining blocks by 50 percent and each block analyzed using the spectral centroid method to obtain depth to the top, centroid and bottom of magnetic sources. The depth values were subsequently used to evaluate the Curie-point depth (CPD), geothermal gradient and near-surface heat flow in the study area. The result shows that the CPD varies between 5.22 and 14.35 km with an average of 9.09 km, the geothermal gradient varies between 40.42 and 111.11 °C/km with an average of 72.24 °C/km, and the resulting heat flow varies between 101.05 and 277.77 mW m−2 with an average of 180.59 mW m−2. Such heat flow values are suggestive of anomalous geothermal conditions and are recommended for detailed geothermal exploration.

Crustal thermal structure of the Farafra oasis, Egypt, based on airborne potential field data

The Farafra oasis is one of the most interesting and promising areas for geothermal energy development in Egypt. The objective of the present study is to evaluate the geothermal potential in the Farafra oasis and its suitability for geothermal development in the Western Desert using different tools such as remote sensing, seismic events, and aeromagnetic and aerogravity data. Remote sensing (Landsat 8 ETM+) was utilized to estimate the land surface temperature (LST) in the Farafra oasis. The resultant map of LSTs indicates that the surface temperature of the Farafra area ranges from 10 °C to 30 °C and that the mean surface temperature of the whole area is approximately 26 °C. Most earthquake events are located to the east and northeast of the Farafra oasis (toward the Bahariya Oasis). However, the highest magnitude event (4.62) is located near the eastern border of the Farafra oasis. One event with a magnitude of 3.08 is located to the south and within the Farafra outline. The distributions of low-magnitude earthquake events can provide information about the locations of active faults, which indicate possible fracture permeability. The interpretation of aeromagnetic data indicates that the Curie point depth (CPD) ranges from 16 km to 26 km with an average of 22 km. The CPDs increase toward the center and north of the Farafra oasis and decrease westward. The interpretation of aerogravity data shows maximum anomalies above four main localities: Ain-Dalla, Bir-Sitta, northeast of Bir-Sitta and at the southern margin of the Farafra oasis, which indicates the existence of vertical or near-vertical contacts (faults) in these areas and provides a good correlation with structural lines on the geological map. Linear features striking NE-SW are pronounced on the tilt gradient map.

Curie point depths in Northeast China and their geothermal implications for the Songliao Basin

This work integrates processing and interpretation of the combined geomagnetic anomaly model of NGDC-720-V3.1 to better constrain thermal structures of the Northeast China lithosphere, which shows intensive extension and active volcanism during the Mesozoic and Cenozoic. Numerical tests demonstrate that magnetic anomalies calculated at 20 km altitude can be used for accurate Curie depth estimation. Averaged Curie depths using a 3D fractal exponent of 3.0 vary from ∼13±2.0 to 33±4.1 km with a mean of ∼22±2.4 km in Northeast China. With temperature-dependent thermal conductivity models constrained by incorporated surface heat flow and Curie depths in different geological blocks, the thermal lithospheric thicknesses are estimated mostly between 45 and 90 km based on 1D steady-state thermal conduction equation. Beneath the Songliao Basin, the Moho temperatures are abnormally high, ranging from ca. 700 to 1000 °C, and the mantle contributes about 65% of the total surface heat flow. The shallow Curie points and thermal lithosphere-asthenosphere boundary, together with high Moho temperatures and mantle heat flow, support abnormally high geotherms in the Songliao Basin, originated from hot upper mantle upwelling triggered likely by lithospheric delamination.

Effects of the Karacadag Volcanic Complex on the thermal structure and geothermal potential of southeast Anatolia

The Karacadag Volcanic Complex (KVC) is the largest volcanic unit in SE Turkey. It is also defined as a shield volcano on the northernmost part of the Arabian Plate. The main goal of this study is to investigate the geothermal potential of this region associated with the magnetic signature of this volcanic complex and surrounding area. Besides this primary objective, the possibility of there being volcanic intrusion into the buried fault zones under the volcanic cover are also investigated to determine the interrelations between the active tectonics and heat flow in the area. A spectral analysis method is applied to the magnetic anomalies of the volcanic rocks to identify the Curie point depth (CPD) and geothermal gradient, as well as to estimate heat flow and radiogenic heat production of radioactive minerals in the complex. A tilt angle map is also presented, in correlation with instrumentally recorded earthquake magnitudes, to indicate tectonic trends that are consistent with the maps of the thermal parameters in this study. In contrast with expectations for the KVC area, the region around Akcakale and Suruc Grabens is the most prolific zone for geothermal potential, despite them not showing strong magnetic anomalies. Curie point depths are shallow, down to 18 km, around the Akcakale Graben, and deeper, down to 22 km, around the Bitlis-Zagros Suture Zone where the geothermal gradients increase from 26 to 32 °C km−1 through the graben area. Heat flows in this zone are in the range from 75 to 90 mW m−2 depending on the thermal conductivity coefficient (2.3, 2.5, 2.7, and 3.0 W m−1 K−1) used. Radiogenic heat production values also indicate slightly changing spectra in the range 0.19 to 0.25 μW m−3). None of these parameters are focused around Mt. Karacadag. However, the earthquake epicenters (generally M ≤ 4) are aligned with the boundary faults of the Akcakale Graben where the CPD, geothermal gradient, and heat flow maps indicate relatively high potential. We thus suggest that this graben area would be good for future geothermal exploration. On the contrary, considering the low geothermal gradient and heat flow values, Mt. Karacadag can be accepted as being an extinct volcano, despite its apparent, high, magnetic anomalies.

Interpretation of High Resolution Aeromagnetic Data to Estimate the Curie Point Depth Isotherm of Parts of Middle Benue Trough, North-East, Nigeria

Interpretation of High Resolution Aeromagnetic Data to Estimate the Curie Point Depth Isotherm of Parts of Middle Benue Trough, North-East, Nigeria

Thermal structure of the Panama Basin by analysis of seismic attenuation

Using recordings of earthquakes on Oceanic Bottom Seismographs and onshore stations on the coastal margins of Colombia, Panama, and Ecuador, we estimate attenuation parameters in the upper lithosphere of the Panama Basin. The tomographic images of the derived coda-Q values are correlated with estimates of Curie Point Depth and measured and theoretical heat flow. Our study reveals three tectonic domains where magmatic/hydrothermal activity or lateral variations of the lithologic composition in the upper lithosphere can account for the modeled thermal structure and the anelasticity. We find that the Costa Rica Ridge and the Panama Fracture Zone are significant tectonic features probably related to thermal anomalies detected in the study area. We interpret a large and deep intrinsic attenuation anomaly as related to the heat source at the Costa Rica Ridge and show how interactions with regional fault systems cause contrasting attenuation anomalies.

Curie Point Depth of the Iberian Peninsula and Surrounding Margins. A Thermal and Tectonic Perspective of its Evolution

AbstractIn this work the thermal structure of the Iberian Peninsula is derived from magnetic data by calculating the bottom of the magnetization, assumed to be the Curie‐point depth (CPD) isotherm, which accounts for the depth at which magnetite becomes paramagnetic (580°C). Comparison of the CPD with crustal thickness maps along with a heat flow map derived from the CPD provides new insights on the lithospheric thermal regime. Within Iberia, the CPD isotherm has thickness in the range of 17 to 29 km. This isotherm is shallow (<18 km) offshore, where the lithosphere is thinner. In continental Iberia, the NW Variscan domain presents a magnetic response that is most probably linked to thickening and later extension processes during the late Variscan Orogeny, which resulted in widespread crustal melting and emplacement of granites (in the Central Iberian Arc). The signature of the CPD at the Gibraltar Arc reveals a geometry consistent with the slab roll‐back geodynamic model that shaped the western Mediterranean. In offshore areas, a broad extension of magnetized upper mantle is found. Serpentinization of the upper mantle, probably triggered in an extensional context, is proposed to account for the magnetic signal. The Atlantic margin presents up to 8 km of serpentinites, which, according to the identification of exhumed mantle, correlates with a hyperextended margin. The Mediterranean also presents generalized serpentinization up to 6 km in the Algerian Basin. Furthermore, a heat flow map and a Moho temperature map derived from the CPD are presented.

Modeling of the Foca-Uzunada magnetic anomaly and thermal structure in the gulf of Izmir, western Turkey

The Gulf of Izmir (GoI) is one of the largest gulfs in the Aegean Sea, Turkey. There is a large magnetic anomaly extending in the NE-SW direction between Foca and Uzunada (Uzun Island) in the gulf. Previously, Curie Point Depth (CPD), geothermal gradient, heat-flow and radiogenic heat production maps of the onshore part of the Aegean region were constructed from the aeromagnetic data. In this study, the same maps except radiogenic heat production map are presented for the offshore part and the largest magnetic anomaly in the northern part of the gulf is focused, particularly. As a result, the thermal structure of GoI is clearly defined and according to the results of this study, CPD values were found from 7 km in the NE of Foca to 10 km through the south of the gulf. The geothermal gradient values vary between 50 and 80 °C/km. Maximum heat flow values around the anomaly are calculated as 200 and 215 mW/m2 according to the thermal conductivity coefficients of 2.5 W m−1 K−1 and 2.7 W m−1 K−1, respectively. Although the anomaly is located in the Izmir Gulf; CPD, geothermic gradient, heat flow anomalies are shifted through the north of Foca and Aliaga towns in the Candarli Bay. This prominent anomaly in the Gulf of Izmir is associated with the magmatics that were encountered at 969 m in the Foca-1 well although it was drilled about 2 km away from the outermost closed contour of the magnetic anomaly. The anomaly is also modeled three dimensionally (3D) in this study. In the model map, the top of the causative body is completely located in the outer part of the gulf, and is very shallow at about 0.5 km while its bottom is inclined through the west of Cigli and Menemen. From this viewpoint, it is possible to suggest that the causative body is inclined through the Foca Peninsula. However, its closed contours are in the NE direction, through the Candarli Bay. Top depth of the causative body is also calculated from the basement horizon on the seismic sections crossing this anomaly. Depth calculations are consistent in these sections and confirm the top depths from the modeling study. The basement geometry in the seismic sections also reflects the shape of 3D model geometry, and bottom depth of the magmatics is also verified by the basement depth calculations in seismic sections.

Determination of Geothermal Energy Sources in Masu Area Northeastern Nigeria Using Spectral Analysis of Aeromagnetic Data

The incessant power outage and power rationing in Nigeria has affected the economic development, hence the need to seek for other sources of electricity generation such as geothermal energy which is environmentally friendly and renewable. The wide range of geologic formations in the north-eastern Nigeria provides an avenue for exploration of geothermal energy. Hence, this work carries out an investigation of Curie point depth, geothermal gradient as well as heat flow in Masu, which is located within Nigerian sector of Chad Basin (lat. 12°00' to 13°00' N and long. 12°30' to 14°00' E) using spectral analysis. Application of minimum curvature in gridding the total magnetic field intensity data was done using the Oasis Montaj 6.4.2 software. First order polynomial fitting was applied in Regional-residual separation. The Curie point depth obtained ranges from 12.233 to 16.184 km with an average of 13.993 km, the geothermal gradient of the area varies from 35.838 to 47.413°C /km, with an average of 41.821°C /km, while the heat flow ranges from 89 to 117.80 mWm^-2, with an average of 104.551 mWm^-2. The 2D contour maps reveal that the Curie point depth is lowest in the southeast and increases towards the northwest, while the geothermal gradient and heat flow on the other hand are highest in the southeast and decrease towards northwest. The high geothermal gradient and heat flow values in the area are indications that the area might be suitable for geothermal energy generation as an alternative power supply in the area and in the country at large.

Curie Point Depth (CPD) Investigation Of Offshore Niger Delta Using High Resolution Aeromagnetic Data

Offshore Niger Delta, Nigeria, is known to be a hub for hydrocarbon exploration within the West Africa region and the world in general. The geologic settings within the Niger Delta province have a proven potential to assist in oil and gas exploration. However, much of the offshore provinces potential remains unknown with respect to the temperature differences using aeromagnetic data. In the present research, high resolution aeromagnetic data covering longitude 4°30i E - 5° E and latitude 3°30iN - 4°30N with an approximate area of about 6050 km2 was used to estimate the Curie Point Depth (CPD) of the study area. For this aim to be realizable, regional-residual was undertaken on the Total Magnetic Intensity (TMI) data. This art gave rise to the regional and the residual maps. The residual map was then after divided into thirty five overlapping spectral grids. Spectral analysis was performed on each of the grids and this decomposed each grid into its energy and frequency segments. The results show three depth models, namely the depth due to the deeply seated sources or the centroid depth, Dc, depth due to the shallow magnetic sources, Dt and the depth at which minerals lose their ferromagnetic properties or the basal depth, Db. However, Dc varies from - 9950 m to - 35294.12 m but with a true or average depth value of - 9751.75 m while Dt lies between -1250 m and -3684.21 but with a true depth of - 2000 m. Similarly, the basal depth ranges from -9950 m to -35294.12 m. This study therefore suggests that at a depth of - 9950 m and beyond ferromagnetic minerals turn into a paramagnetic one within the area of study.