Abstract
Locating zones of possible mineralization potentials in part of southwestern Nigeria has been performed in this work by mapping lithology, structures, and hydrothermal alteration regions from airborne magnetic and radiometric data. Some enhancement techniques such as first vertical derivative, analytic signal, power spectrum, and center for exploration targeting grid and porphyry were used for data analysis and interpretation; in addition, the potassium to equivalent thorium (K/eTh) ratio and ternary radiometric maps were revealed to support the delineation process. The results obtained showed that the area is dominated by NE–SW, NW, NE, EW, and NS structural directions, though the structures trending NE–SW were found to be the most predominant and considered to be orientations of mineral deposits in the area. Depth estimation of shallow and deep-seated magnetic sources of the reduction to the equator (RTE) aeromagnetic data calculated using the analytic signal technique ranged from 270 to 2800 m, while power spectrum gives an average value of 2960 m. In addition, aeroradiometric analysis based on the concentrations of equivalent thorium and equivalent uranium and potassium and on the radiometric ternary map revealed lithological units and hydrothermal alterations within the basement complex. From this study, volcanic intrusions, lineament structures, and hydrothermal alteration zones were delineated. These intrusions resulted from the high content of magnetic anomalies related to the mineralized potential zones in the area. The integration of both magnetic and radiometric maps has revealed an approximate understanding between radiation zones, observed fractures, and faults in the locations between the boundaries of rock types in the study area.
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References
Adelusi AO, Kayode JS, Akinlalu AA (2013) Interpretation of aeromagnetic anomalies and electrical resistivity mapping around Iwaraja area Southwestern Nigeria. JGMR 5(2):38–57
Ahmed SB (2018) Integration of airborne geophysical and satellite imagery data to delineate the radioactive zones at west Safaga Area, Eastern Desert, Egypt. NRIAG J Astron Geophys 7(2):297–308
Akpan OU, Yakubu TA (2010) A review of earthquake occurrences and observations in Nigeria. Earthq Sci. Springer 23(3):289–294
Al-Badani MA, Al-Wathaf YM (2017) Using the aeromagnetic data for mapping the basement depth and contact locations, at southern part of Tihamah region, Western Yemen, Egypt. Egypt J Pet. https://doi.org/10.1016/j.ejpe.2017.07.015
Awoyemi MO, Hammed S, Falade MY (2017) Geophysical investigation of the possible extension of Ifewara fault zone beyond Ilesa area, southwestern Nigeria. Arab J Geosci 10(2):27. https://doi.org/10.1007/s12517-016-2813-z
Balogun OB (2019) Tectonic and structural analysis of the Migmatite–Gneiss–Quartzite complexof Ilorin area from aeromagnetic data. NRIAG J Astron Geophys 8(1):22–33
Cooper GRJ (2006) Interpreting potential field data using continuous wavelet transforms of their horizontal derivatives. Comput Geosci 32984–992
Eldosouky AM, Abdelkareem M, Elkhateeb SO (2017) Integration of remote sensing and aeromagnetic data for mapping structural features and hydrothermal alteration zones in Wadi Allaqi area, South Eastern Desert of Egypt. J Afr Earth Sci. Elsevier 130:28–37
Elkhateeb SO, Abdellatif MAG (2018) Delineation potential gold mineralization zones in a part of Central Eastern Desert, Egypt using Airborne Magnetic and Radiometric data. NRIAG J Astron Geophys 7(2):361–376
Evjen HM (1936) The place of the vertical gradient in gravitational interpretations. Geophysics. Society of Exploration Geophysicists 1(1):127–136
Falebita DE (2008) Integrated geophysical mapping of the Ifewara transcurrent fault system, Nigeria. J Afr Earth Sci 52:161–166
Hinze WJ, Von Frese RRB, Saad AH (2013) Gravity and magnetic exploration: principles, practices, and applications. Cambridge University Press
Holden EJ, Kovesi P, Dentith M, Wedge D, Wong JC, Fu SC (2010) Detection of regions of structural complexity within aeromagnetic data using image analysis. Twenty Fifth International Conference of Image and Vision Computing New Zealand, 8–9 November 2010.
Holden EJ, Fu S, Kovesi P (2011) Automatic identification of responses from porphyry intrusive systems within magnetic data using image analysis. J Appl Geophys. Elsevier 74(4):255–262
Ibraheem IM, Haggag M, Tezkan B (2019) Edge detectors as structural imaging tools using aeromagnetic data: a case study of Sohag Area, Egypt. Geosciences. Multidisciplinary Digital Publishing Institute 9(5):211
IGRF (2010) International Geomagnetic Reference Field
Jayeoba A, Odumade D (2015) Geological and structural interpretation of Ado-Ekiti Southwest and its adjoining areas using aeromagnetic data. Adapted from extended abstract prepared in conjunction with oral presentation given at Pacific Section AAPG, SEG and SEPM Joint Technical Conference, Oxnard, California, May 3-5, 2015
Kayode JS, Adelusi AO, Nyabeze PK (2013) Interpretation of ground magnetic data of Ilesa, Southwestern Nigeria for potential mineral targets. Adv Appl Sci Res 4(1):163–172
Kearey P, Brooks M, Hill I (2013) An introduction to geophysical exploration. John Wiley & Sons
Kovesi P (1991) Image features from phase congruency Videre: Journal of Computer Vision Research, Summer. (1) 3 The MIT Press.
Lawal TO, Nwankwo LI (2017) Evaluation of the depth to the bottom of magnetic sources and heat flow from high resolution aeromagnetic (HRAM) data of part of Nigeria sector of Chad Basin. Arab J Geosci:1–12. https://doi.org/10.1007/s12517-017-3154-2
Lawal TO, Salawu NB, Orosun MM, Ekpumoh JI, Nwankwo LI (2016) Application of 3-D Euler deconvolution technique to aeromagnetic data of Ilorin and Osi, North central Nigeria. Zimbabwej Sci Technol 11:66–75
Miller HG, Singh V (1994) Potential field tilt—a new concept for location of potential field sources. J Appl Geophys. Elsevier 32(2–3):213–217
Nabighian MN (1972) The analytic signal of two-dimensional magnetic bodies with polygonal cross-section: its properties and use for automated anomaly interpretation. Geophysics. Society of Exploration Geophysicists 37(3):507–517
Nuhu GO (2009) Geology and mineral resources of Nigeria, Lecture Notes in Earth Sciences. 120, Springer-Verlag, Berlin Heidelberg
Obaje NG (2009) Geology and mineral resources of Nigeria, 120. Springer
Ogungbemi OS, Amigun JO, Olayanju GM (2018) Geophysical characterization of mineralization potential of eastern parts of Ife-Ijesha Schist-Belt, southwestern Nigeria. Int J Sc and Tech R 7(3):21–27
Ostrovskiy EA (1975) Antagonism of radioactive elements in well rock alteration fields and its use in aerogamma spectrometric prospecting. Int Geol Rev 17:461–468. https://doi.org/10.1080/00206817509471687
Ozebo VC, Ogunkoya CO, Makinde V, Omeike MO (2015) An estimation of magnetic contact location and depth of magnetic sources in Ilesha, Nigeria, using magnetic gradient techniques. Afri Rev of Phy 10(1):17–26
Phillips JD (2000) Locating magnetic contacts: a comparison of the horizontal gradient, analytic signal, and local wavenumber methods. in SEG Technical Program Expanded Abstracts 2000. Society of Exploration Geophysicists. 402–405.
Phillips JD (2007) Geosoft eXecutables (GX’s) developed by the U.S. Geological Survey, version 2.0, with notes on GX development from Fortran code: U.S. Geological Survey Open-File Report 2007–1355
Saada SA (2016) Edge detection and depth estimation of Galala El Bahariya Plateau, Eastern Desert-Egypt, from aeromagnetic data. Geomech Geophys Geo-energ Geo-resour (2):25–41
Salawu NB, Olatunji S, Leke SA, Nurudeen K (2019) Edge detection and magnetic basement depth of Danko area, northwestern Nigeria, from low-latitude aeromagnetic anomaly data. SN Appl Sci 1(9):1056
Salem A, Williams D, Fairhead E (2007) Interpretation of magnetic data using tilt-angle derivatives. Geophysics. Society of Exploration Geophysicists 73(1):L1–L10
Shives RBK, Charbonneau BW, Ford KL (2000) The detection of potassic alteration by gamma-ray spectrometry—recognition of alteration related to mineralization Detecting ore Using GRS and K Alteration. Geophysics. GeoScienceWorld 65(6):2001–2011
Silva AM, Pires ACB, Mccafferty A, de Moraes RAV, Xia H (2003) Application of airborne geophysical data to mineral exploration in the uneven exposed terrains of the Rio Das Velhas Greenstone Belt. Revista Brasileirade Geociências 33(2): 17–28
Spector A, Grant FS (1970) Statistical models for interpreting aeromagnetic data. Geophysics 35:293–302
Telford WM, Geldart LP, Sheriff RE (1990) Applied geophysics. Cambridge University Press
Wemegah DD, Preko K, Noye RM, Boadi B, Menyeh A, Danuor SK, Amenyoh T (2015) Geophysical interpretation of possible gold mineralization zones in Kyerano, South- Western Ghana using aeromagnetic and radiometric datasets. J Geosci Environ Prot 3:67–82
Youssef MAS, Elkhodary ST (2013) Utilization of airborne gamma ray spectrometric data for geological mapping, radioactive mineral exploration and environmental monitoring of southeastern Aswan city, South Eastern Desert, Egypt. Geophys J Int. Oxford University Press 195(3):1689–1700
Acknowledgments
The author sincerely appreciates the constructive reviews of the anonymous reviewers for their meaningful thoughts that brought in excellence to this manuscript. Many thanks are given to the Nigeria Geological Survey Agency (NGSA) for releasing the HRAM data at a subsidized rate and to Mr. Taiwo Adewumi for his assistance towards securing the SRTM data.
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Responsible Editor: Domenico M. Doronzo
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Lawal, T.O. Integrated aeromagnetic and aeroradiometric data for delineating lithologies, structures, and hydrothermal alteration zones in part of southwestern Nigeria. Arab J Geosci 13, 775 (2020). https://doi.org/10.1007/s12517-020-05743-7
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DOI: https://doi.org/10.1007/s12517-020-05743-7