Fig 1 - uploaded by Solomon Nehemiah Yusuf
Content may be subject to copyright.
Source publication
Source Parameter Imaging (SPI) technique was used to analysed high resolution aeromagnetic data over the Nigerian sector of the Chad Basin. First order polynomial fitting was used for Regional-Residual separation and thereafter, all analyses were carried out on the residual data. The results show three well-defined sub-basins named the Baga, Gubio...
Context in source publication
Citations
... The climate is characterized by a long dry season. The Nigerian sector of the Chad Basin constitutes about 6.5% of the entire basin and extends an area of 152,000 km 2 (Goni et al., 2016). ...
... Based on this fact, the negative magnetic field anomalies observed in the aforementioned parts of the ditto study area were interpreted as felsic rocks associated with low magnetic susceptibility, while the positive magnetic field anomalies observed in the study area may be interpreted as mafic and ultramafic rocks beneath the sedimentary cover of the central part, north-western half and south-western half at shallow depths. Previous studies (Abubakar, 2004;Lawal et al., 2006;Goni et al., 2016;Sanusi, 2015) have inferred presence of these rocks beneath Bornu basin of Nigeria. Thickness of the sedimentary cover is very crucial in assessing the hydrocarbon prospectivity of the sedimentary basins, as the thicker the sedimentary cover the higher the subsurface temperature, which controls the maturation of potential source rocks, and controls the fluid accumulation and temperature of the geothermal reservoir. ...
... Adewumi et al. (2017) estimated the sedimentary thickness in some part of the study area between 0.29 and 3.35 km, using conventional spectral analysis of aeromagnetic data. Goni et al. (2016) estimated the sedimentary thickness of the basin, using Source Parameter Imaging (SPI) method, three areas were found to have appreciable sedimentary thickness situated around Baga, Gubio and Damboa sub-basins. Maximum depth to basement of over 6 km has been recorded towards western part of the Gubio Sub-basin. ...
The Curie point depth is the depths at which subsurface temperature (approximately 580 oC) loses spontaneous magnetization within the rock units and magnetic minerals show features of paramagnetic susceptibility. In this research work sedimentary thickness and Curie point depths of the eastern parts of Bornu basin were investigated. The aeromagnetic data was subdivided into twenty-five (25) overlapping blocks, and each block was analyzed to obtain depth to basement (Zt) of the magnetic sources and depth to centroid (Zo). The depth values were then used to estimate CPD and Curie temperature (𝜃) within the study area. The result shows that the depth to basement (Zt) varies between 2.55 and 7.4 km, with an average value of 5.96 km, the depth to centroid (Zo) values varies between 8.4 and 14.15 km with an average value of 11.08 km, the CPD values varies between 15.11 and 19.0 km with an average value of 16.20 km.
The high resolution aeromagnetic data of the Bornu Basin obtained from Nigeria geological survey agency (NGSA)were used to estimate the sedimentary thickness of the Bornu Basin. 1st order polynomial fitting was used on the total magnetic intensity field data for regional-residual separation,with the residual data obtained used to carry out spectral analyses. The study area was divided into 94 blocks of 27.5 km x 27.5 km. Results obtained identified twodepressions in the southerneastern part of Gubio extending to Mafa and the Kukawa-Bagaand with sedimentary thicknesses ranging from 2.8 to 3.2 Km. Areas of shallow depth to basement were interpretedas volcanic intrusions/uplifted basement, which are associated with the Santonian deformation.Thicknesses of the sedimentary cover obtained over the study area fell above the generally accepted threshold range of 2 to 4 km for hydrocarbon generation. Therefore, based on the sedimentary thicknesses obtained, prospectivity of hydrocarbon in the Bornu Basin is good.
The high resolution aeromagnetic data of the Bornu Basin obtained from Nigeria geological survey agency (NGSA)were used to estimate the sedimentary thickness of the Bornu Basin. 1st order polynomial fitting was used on the total magnetic intensity field data for regional-residual separation,with the residual data obtained used to carry out spectral analyses. The study area was divided into 94 blocks of 27.5 km x 27.5 km. Results obtained identified twodepressions in the southerneastern part of Gubio extending to Mafa and the Kukawa-Bagaand with sedimentary thicknesses ranging from 2.8 to 3.2 Km. Areas of shallow depth to basement were interpretedas volcanic intrusions/uplifted basement, which are associated with the Santonian deformation.Thicknesses of the sedimentary cover obtained over the study area fell above the generally accepted threshold range of 2 to 4 km for hydrocarbon generation. Therefore, based on the sedimentary thicknesses obtained, prospectivity of hydrocarbon in the Bornu Basin is good.
