Geophysical investigation for mineral prospect in Igbeti-Moro area, Southwestern Nigeria



geologic features, lineament, Fast Fourier transform, magnetic anomalies, mineralization


To establish significant geologic features associated with the marble, gabbro and muscovite mineralization in Igbeti-Moro area, within southwestern Nigeria, the high-resolution aeromagnetic data were subjected to data enhancement processes and interpretation. The reduced-to-magnetic equator (RTE) anomaly map was subjected to various normalized (vertical, tilt and total horizontal) derivatives for lineament enhancement, edge detection of analytic signal (AS) amplitude and depth estimation techniques of source parameter imaging (SPI), average power spectrum and magnetic source depths were estimated using the source parameter imaging averaged power spectrum and Euler deconvolution at different spectral indices. The range of RTE residual magnetic intensity from 338.3 nT to -2.4 nT (low), 9.9 to 27.7 nT (intermediate) and 32.1 to 208.0 nT (high)  revealed the three major lithologies in the area which include the: Pan African Granite, early metamorphic tectonites, metasedimentary rocks and the intrusion of quartz and amphibolite schists. The prominent NE – SW lineament revealed regional structural grains (fractures and faults) in these rocks associated with emplacement of the quartz-schist and muscovite-schist, which would have formed contemporaneously with isoclinal fold and hosts marble, gabbro, amphibolites, and muscovite mineralogy at shallow depth range 0 to 200 m in the western, north central and northeastern parts of the area. The significant geologic features and their geometry of occurrences have been established as a prospect for solid minerals in the area. However, geochemical investigation is encouraged to determine the economic value of the minerals.

Keywords: geologic features; lineament; mineralogy; magnetic anomalies; regional structural grains.

Author Biography

Nurudeen Kolawole Olasunkanmi, Kwara State University, Malete. Nigeria

Lecturer; Physics and Materials Science Department


Amigun, J. O., Afolabi, O., & Ako, B. D. (2012). Application of airborne magnetic data to

mineral exploration in the Okene Iron Ore Province of Nigeria. International Research Journal

of Geology and Mining (IRJGM), 132-140.

Baranov, V. (1957). A new method for interpretation of aeromagnetic maps. Geophysics , 359 - 383.

Blakely, R. J. (1995). Potential Theory in Gravity and Magnetic Applications. Cambridge Univ. Press.

Blakely, R. J., & Simpson, R. W. (1986). Locating edges of source bodies from magnetic and gravity anomalies. Geophysics , 51 (7), 1494 - 1498.

Biyiha-Kelaba, W., Ndougsa-Mbarga, T., Yene-Atangana, J., Ngoumou, P. C., &

Tabod, T. C. (2013). 2.5D Models Derived from the Magnetic Anomalies Obtained by

Upwards Continuation in the Mimbi Area, Southern Cameroon. Journal of Earth Sciences and

Geothecnical Engineering, 3(4), 175-199.

Burke, K. C., & Dewey, J. F. (1972). Orogeny in Africa. In T. F. Dessauvagie, & A. J. Whiteman, Africa geology (pp. 583–608). Ibadan: University of Ibadan Press.

Cooper, G. R., & Cowan, D. R. (2004) Filtering using variable order vertical derivatives.

Computers & Geosciences , 455-459.

Egbuniwe, I. G., (1980) The geology of Part of South Western Nigeria, Geological Survey of Nigeria Bulletin (Ed) 31 (26):1-47

Fairhead, J. D., & Williams, S. E. (2006) Evaluating Normalized Magnetic Derivatives for Structural Mapping. SEG 2006 New Orleans Extended Abstract. SEG.

Hanna, W. F. (1969). Negative aeromagnetic anomalies over mineralized areas of the boulder

batholith, Montana. Gelo. Survey Prof. Paper, 650, D155 - D167.

Hans, T. (2012). Magnetic survey at Nesodden - survey and interpretation report. Lulea:

GeoVista AB.

Intrepid, (2012). Estimating Source Depth. Intrepid Geophysics.

Jayeoba, A., & Odumade, D. (2015). Geological and Structural Interpretation of Ado-Ekiti

Southwest and its Adjoining Areas Using Aeromagnetic Data. Pacific Section AAPG, SEG and

SEPM Joint Technical Conference. Oxnard, California: AAPG.

Jacobsen, B. H. (1987). A case for upward continuation a sa standard seperation filter for

potential field maps. Geophysics, 1138 - 1148.

John, M. J., Marianne, E. P., & Antony, D. P. (2003). Improving geologic understanding

with gravity and magnetic data: Examples from Gabon, Nigeria and the Gulf of Mexico. EAGE,

pp. 57-62.

McGraw, H. (2003). Dictionary of geology and mineralogy (2nd ed.). United State of

America:McGraw-Hill Companies.

Moghaddam, M., Mohammad, S., Saeid, M., & Nasim, H. (2015). Interpretation of

Aeromagnetic Data to Locate Buried Faults in North of Zanjan Province, Iran. J Remote

Sensing & GIS, 4(2), 1 - 5.

Nabighian, M. N. (1972). The analytic signal of two-dimensional magnetic bodies with

polygonal cross-section: its properties and use for automated anomaly interpretation.

Geophysics, 507-517.

Nabighian, M. N., Grauch, J. S., Hansen, R. O., LaFehr, T. R., Li, Y., Pierce, J. W., . . .

Ruder, M. E. (2005). The historical development of the magnetic method in exploration.

Geophysics, 33 - 61.

Nigerian Geological Survey Agency, (2008). Airborne Geophysical Survey: Total Magnetic

Intensity of Igbeti (Sheet 201).

Nigerian Geological Survey Agency, (2006). Geological map of Igbeti-Moro (Sheet 201) Area.

Obaje, N. G. (2009). Geology and Mineral Resources of Nigeria. In Lecture Notes in Earth Sciences. Berlin Heidelberg: Springer.

Oladunjoye, M. A., Olayinka, A. I., Alaba, M., & Adabanija, M. A. (2016). Interpretation

of high resolution aeromagnetic data for lineaments study and occurence of banded iron

formation in Ogbomoso area, Southwestern Nigeria. Journal of African Earth Sciences, 43-53.

Paananen, M. (2013). Complete lineament interpretation of the Oikiluoto region. Posiva,

-02 ISBN 978-951-652-234-3.

Rahaman, M.A., Emofurieta, W.O. Vanchette, M.C., (1983) The Potassic Granites of Igbetti Area: Further evidence of the poly cyclic evolution of the Pan-African Belt in SW Nigeria. Precambrian Research, 22: 75-92.

Reeves, C. (2005). Aeromagnetic Surveys: Principles, Practice and Interpretation. Geosoft.

Richard, A. M. (2001). dictionary of Geophysics, Astrophysics and astronomy. Boca Raton

London New York Washington, D.C.: CRC Press.

Robinson, E. A., & Treitel, S. (2000). Geophysical Signal Analysis. Tulsa, USA: Society of

Exploration Geophysics.

Ross, C. B. (2002). Geophysical and Remote Sensing Methods for Regolith Exploration.

Australia: Geoscience.

Telford, W. M., Geldart, L. P., Sheriff, R. E., & Keys, D. A. (1990). Applied Geophysics.

Cambridge: Cambridge University Press.

Thurston, J. B., Guillon, J. C., & Smith, R. S. (1999). Model independent depth estimation

with the SPITM method. 69th Annual international meeting (pp. 403 - 406). Society of

Exploration Geophysics.

Trompat, H., Boschetti, F., & Hornby, P. (2003). Improved downward continuation of

potential field data. Exploration Geophysics, 249 - 256.

Spector, A., & Grant, F. S. (1970). Statistical models for interpreting Aeromagnetic data.

Geophysics, 293 - 302.

Wynn, J. (2002). Evaluating ground water in arid lands using airborne magnetic and airborne

electromagnetic methods- and example in the southwestern U.S. and northern Mexico. The

Leading Edge, 62 - 65.






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