Investigation of Magnetic Anomalies and Depth to Magnetic Sources Over Igboho Area Using High Resolution Aeromagnetic Data

Authors

  • I. A. Akinlabi
  • Olagoke Peter Oladejo
  • Charles Olubunmi Ogunkoya
    Ajayi Crowther University Oyo

Keywords:

Aeromagnetic, Igboho, Orelope, Source Imaging, Analytic signal, Horizontal derivative, Magnetic Equator

Abstract

The availability of geophysical Information about the presence of magnetic minerals can further showcase the location and depth of suspected minerals, the use of aeromagnetic data over a study area for Investigation of magnetic mineral can provide more information about subsurface geology of the area. Aeromagnetic dataset of Igboho acquired from the Nigeria Geological Survey Agency (NGSA), was processed to map out the geological structures of the area and determine the basement depth to magnetic sources in the study area. Regional correction based on the IGRF value of the study area was carried out on the Total Magnetic Field Intensity (TMFI) values which generates the residual map of the study area. The magnetic enhancement filters including Reduction to Magnetic Equator (RTME), Analytic Signal Amplitude (ASA), and Total Horizontal Derivative (THDR) were further applied to residual total magnetic field intensity data so as to further define the lithological boundaries and magnetic structure locations. This is followed by determination of basement depth to magnetic sources using Euler deconvolution (ED) and Source Parameter Imaging (SPI) techniques. The results of the RTME map generates magnetic anomalies’ amplitude ranging from -37.577 nT to 27.398 nT, the northwest, southeast through southern part of the study area are dominated by high magnetic anomaly. However the definite lithological boundaries and geological structures result generated from THDR is similar to the one obtained from ASA technique. The structural trends observed were in NW, NS and SW directions. The SPI results shows 126.383 m as the shallowest depth to basement magnetic anomalous structures and 1834.659 m for the deepest depth to basement magnetic structures with calculated average depth of 981 m.  The results of the Euler Deconvolution shows an undulating structural basement with estimated depth between -474.253 m and 1266. 027 m. The results also suggested the basement relief of...

Dimensions

Adetona, A., Abbass and Mallam, A. (2013). Estimating the Thickness of Sedimentation within Lower Benue Basin and Upper Anambra Basin, Nigeria, Using Both Spectral Depth Determination and Source Parameter Imaging. International Journal of Geophysics, 20, Vol. 2013(1), pp. 1-11. DOI: https://doi.org/10.1155/2013/124706

Ahmed, S. AL-Banna, A., Daham, N. (2019) Application of Source Parameter Imaging (SPI) Technique to Gravity and Magnetic Data to Estimate the Basement Depth in Diyala Area, Eastern Central Iraq. Iraqi Journal of Science, 60(3): 601-609. DOI: 10.24996/ijs.2019.60.3.18

Amigun1, J. O., Adelusi, A. O. and Ako, B. D. (2012).The application of integrated geophysical methods in oil sand exploration in Agbabu area of Southwestern Nigeria. International Research Journal of Geology and Mining (IRJGM): 2(9) ,243-253

Ansari, A. H. and Alamdar, K. (2009). Reduction to the pole of magnetic anomalies using analytical signal. World Applied Sciences Journal 7(4): 405-409.

Baranov, V. and Naudy, H., (1964). Numerical calculation of the formula of reduction to the magnetic pole. Geophysics, 29:67–79.

Egbeyale G. B., Ogunseye T. T., Adegbenro S. A and Adekunle K. B. (2022). Interpretation of Aeromagnetic data of Oyo area, Southwesthern Nigeria. International Journal of Science Academic Research. 3(3): 3579-3587.

Grant, F.S. (1985). Aeromagnetics, Geology and Ore environments. I magnetite in Igneous, Sedimentary and Metamorphic rocks: An overview. Geoexploration 23: 303-333

Hsu, K. S., Coppens, D. and Shyu, C. T. (2002). Depth to magnetic source using the generalized analytical signal. Geophysics, 63(6): 1947-1957.

Ikumbur, E. B., Ogah, V. E. and Akiishi, M. (2019). Subsurface Structural Mapping over Koton Karifi and Adjoining Areas, Southern Bida Basin, Nigeria, using High-Resolution Aeromagnetic Data." Nigerian Journal of Environmental Sciences and Technology 3(2): 304–316. http://dx.doi.org/10.36263/nijest.2019.02.0151.

Khalil, A. B., Mostafa T. A., H., and Khamis M. (2014). "Analysis of aeromagnetic data for interpretation of seismicity at Fayoum-Cairo area, Egypt." Earth Sciences Research Journal 18(1): 7–13. http://dx.doi.org/10.15446/esrj.v18n1.36938.

Kivior, I., and D. Boyd. (1999). The interpretation of aeromagnetic surveys for hydrocarbon exploration. APPEA Journal 39 (1) 494. http://dx.doi.org/10.1071/aj98030.

Layade, G.O., Makinde V., Bisilimi, A.L. and Ogunkoya, C.O (2019): Determination of Magnetic Source Depth using Local Wave Number (LWN) and Horizontal Gradient Magnitude (HGM) Methods for High Resolution Aeromagnetic Data of Igbeti. Nigerian Journal of Physics (NJP) 28(2); 109-117. Published by the Nigerian Institute of Physics. www.nipngn.org.

Layade G.O., Makinde V., Bisilimi, A.L and Ogunkoya C.O, (2016). Determination of magnetic source depth using Local Wave Number (LWN) and Horizontal Gradient Magnitude (HGM) methods for high resolution aeromagnetic data of Igbeti, Nigerian Journal of Physics Vol. 27 (2) 1-9

Mono, J.A., Ndougsa-Mbarga, T., Bi-Alou, M.B., Ngoh, J.D. and Owono, O.U. (2018). Inferring the Subsurface Basement Depth and the Contact Locations from Aeromagnetic Data over Loum-Minta Area (Centre-East Cameroon). International Journal of Geosciences, 9, 435-459. https://doi.org/10.4236ijg.2018.97028

Mushayandebvu, M. F., Van Driel, P., Reid, A. B. & Fairhead, J. D. 2001, Magnetic source parameters of two-dimensional structures using extended Euler deconvolution. Geophysics, 66:814-823.

Ogunkoya, C. O., Edunjobi, H. O., Layade, G. O., Akinyosade, E.O., and Anie, N. O. (2023): Investigation of subsurface linear structure controlling mineral entrapment using potential field data of Ilesha. International Journal of Innovative Science and Research Technology (IJISRT). 8(6):321-345.

Ogunmola, J.K., Ayolabi, E.A. and Olobaniyi, S.B. (2016) Structural-Depth Analysis of the Yola Arm of the Upper Benue Trough of Nigeria Using High Resolution Aeromagnetic Data. Journal of African Earth Sciences, 124, 32-43. https://doi.org/10.1016/j.jafrearsci.2016.09.008

Oladejo, O. P., Adagunodo, T. A., Sunmonu, L. A., Adabanija, M. A., Enemuwe, C. A. and Isibor, P.O. (2020). Aeromagnetic mapping of fault architecture along Lagos–Ore axis, southwestern Nigeria. Open Geosciences 12: 376–389

Olurin O.T. (2017). Interpretation of high resolution airborne magnetic data (HRAMD) of Ilesha and its environs, Southwest Nigeria, using Euler deconvolution method. Original scientific paper. 227-241. DOI 10.1515/rmzmag-2017-0013.

Osagie, A. U., Abdelhakim, E. and Adekunle A. A. (2021). Structural trends and basement depths across Nigeria from analysis of aeromagnetic data. Journal of African Earth Sciences 178: 104184. http://dx.doi.org/10.1016/j.jafrearsci.2021.104184.

Ozebo, V. C., Ogunkoya, C. O., Layade, G. O. Makinde, V. and Bisilimi, A. L. (2017). Evaluation of Aeromagnetic data of Ilesha area of Oyo State Nigeria using Analytical signal (ASM) and Local wavenumber (LWN), Journal of Applied Environmental Management, Vol. 21 (6) 1157-1161.

Ozebo, V. C., Ogunkoya, C. O., Makinde, V and Omeike, M. O. (2015). An estimate of Magnetic Contact Location and Depth of Magnetic Sources in Nigeria, Using magnetic gradient techniques. African Review of Physics 10:0003

Ozebo V.C., Ogunkoya C.O., Makinde V., & Layade G.O (2014): Source Depth Determination from Aeromagnetic Data of Ilesha, Southwest Nigeria,Using Peter’s Half slope Method. Earth Science Research, 3(1): 41-49. Published by Canadian Centre of Science and Education. Availableonline at http://dx.doi.org/10.5539/est.v3n1p41.

Philips, J.D. (2000). Locating Magnetic Contacts: A Comparison of the Horizontal Gradient, Analytic Signal, and Local Wavenumber Methods. 70th AnnualInternational Meeting, SEG, Expanded Abstracts. 402–405

Phillips, J. D. (1997). Potential Field Geophysical Software for the PC, verson 2.2 U.SGS open-File Report 97-725.

Reeves C. (2007). Aeromagnetic surveys, principle practice and interpretation. Geosoft E-Publication.

Reeves, C. (2007): Aeromagnetic Surveys: principle, practice and interpretation. Geosoft INC, 155 p

Reid, A. B. and Thurston, J. B., (2014). The structural index in gravity and magnetic interpretation: Errors, uses, and abuses, Geophysics, 79 (4): J61–J66.

Reid, A.B., Allsop, J.M. Granser, H. Millett A.J. and Somerton I.W. (1990). Magnetic interpretation in three dimension using Euler deconvolution, Geophysics, 55: 80-91.c

Robert S. (1965). Alaafin in Exile: A study of Igboho period in Oyo history. The Journal of African history. 6(1):57-77.

Salem, A., Williams, S., Fairhead, J. D., Ravat, D. & Smith, R. (2007). Tilt depthmethod: A simple depth estimation method using first-order magnetic derivatives.The Leading Edge, 26:1502–1505, doi: 10.1190/1.2821934.

Thompson, D. T. (1982). EULDPH): A new techniques for making computer-assisted depth estimate from magnetic data. Geophysics, 47:31-37

Thurston, J. B., and Smith, R. S. (1997). Automatic Conversion of Magnetic Data to Depth, Dip, and Susceptibility Contrast Using the SPI (TM) Method. Geophysics 62 (3): 807–813. doi:10.1190/1.1444190

Whitehead, N., and Musselman, C., (2008). Montaj Grav/Mag Interpretation: Processing, Analysis and Visualization System for 3D Inversion of Potential Field Data for Oasis montaj 63 pp

Wilsher, W.A. (1987) A Structural Interpretation of the Witwatersrand Basin through the Application of Automated Depth Algorithms to Both Gravity and Aeromagnetic Data. M.Sc. Thesis, University of Witwatersrand, Johannesburg.

Published

2023-11-21

How to Cite

Akinlabi, I. A., Oladejo, O. P., & Ogunkoya, C. O. (2023). Investigation of Magnetic Anomalies and Depth to Magnetic Sources Over Igboho Area Using High Resolution Aeromagnetic Data. Nigerian Journal of Physics, 32(3), 79-89. https://njp.nipngr.org/index.php/njp/article/view/121

Issue

Vol. 32 No. 3 (2023): Nigerian Journal of Physics - Vol. 32 No. 3

Section

Articles
Copyright & Licensing

How to Cite

Akinlabi, I. A., Oladejo, O. P., & Ogunkoya, C. O. (2023). Investigation of Magnetic Anomalies and Depth to Magnetic Sources Over Igboho Area Using High Resolution Aeromagnetic Data. Nigerian Journal of Physics, 32(3), 79-89. https://njp.nipngr.org/index.php/njp/article/view/121