Determination of the Structural Lineaments in the Kribi-Campo-Ma’an Area from a Multi-Scale Analysis of Gravity Data Using the HGM and Euler 3D Deconvolution Approaches
With the aim to produce a detailed structural map and
then enhance the geological information of the south-western Cameroon, a field gravity study is carried
out in the Kribi-Campo-Ma’an area (SW Cameroon). This study area is assumed to
undergo pending active tectonics as witnessed by several earthquakes [1]. Besides, the area has been affected by some shears
that gave rise to many major faults including the Kribi-Campo Fault (KCF). This
N-S lineament is an active fault corresponding to the NW margin of the CC[2][3] and related to the
development of the Kribi-Campo basin. The gravity data analysis enables to highlight many deeply-seated structural features trending in the NE, NNE,
N-S, NNW, NW and E-W directions in this region. The NW-SE trend is more
strongly developed than the other identified trends and could have deeply
affected the major NNE structure. The NNE-SSW to N-S fractures and faults which
are local relays of the Kribi-Campo fault are related to the Kribi shear zone.
The fairly good clustering observed on local maxima of the horizontal gradient
magnitude enables to suggest that the contacts outlined have vertical
to subvertical dips. However, a probable interpretation of these features is
that they are vertical to subvertical faults which follow the aforementioned
directions. The location of the study area in the gulf of Guinea suggests
References
[1]
Owona Angue, M.L.C., Tabod, C.T., Nguiya, S., Kenfack, J.V. and TokamKamga, A.P. (2013) Delineation of Lineaments in South Cameroon (Central Africa) Using Gravity Data. Open Journal of Geology, 3, 331-339. http://dx.doi.org/10.4236/ojg.2013.35038
[2]
Owona Angue, M.L.C., Nguiya, S., Nouayou, R., TokamKamga, A.P. and Manguelle-Di- coum, E. (2011) Geophysical Investigation of the Transition Zone between the Congo Craton and the Kribi-Campo Sedimentary Basin (South-West Cameroon). South African Journal of Geology, 114, 145-158. http://dx.doi.org/10.2113/gssajg.114.2.145
[3]
Tadjou, J.M., Nouayou, R., Kamguia, J., Kande, H.L. and Manguelle-Dicoum, E. (2009) Gravityanalysis of the Boundary between the Congo Craton and the Pan-African Belt of Cameroon. Austrian Journal of Earth Sciences, 102, 71-79.
[4]
Ngako, V., Njonfang, E., Aka, F.T., Affaton, P. and Nnange, J.M. (2006) The North-South Paleozoic to Quaternary Trend of Alkaline Magmatism from Niger-Nigeria to Cameroon: Complex Interaction between Hotspots and Precambrian Faults. Journal or African Earth Sciences, 45, 241-256. http://dx.doi.org/10.1016/j.jafrearsci.2006.03.003
[5]
Nzenti, J.P., Barbey, P., Macaudiere, J. and Soba, D. (1988) Origin and Evolution of Late Precambrian High-Grade Yaoundé Gneisses. Precambrian Research, 38, 91-109. http://dx.doi.org/10.1016/0301-9268(88)90086-1
[6]
Maurizot, P., Abessolo, A., Feybesse, J.L., Johan, V. and Lecomte, P. (1986) Etude et prospection minière du sud-ouest Cameroun. Synthèse des travaux de 1978 à 1985. Rapport, BRGM, 274 p.
[7]
Tadjou, J.M., Manguelle-Dicoum, E., Nguiya, S. and Kamguia, J. (2008) Caractéristiques des anomalies gravimétriques du sous-bassin sédimentaire de Kribi-Campo (Sud- Cameroun). Africa Geoscience Review, 1-2, 39-50.
[8]
OwonaAngue, M.L.C. (2012) Investigation géophysique de la zone de transition entre le sous-bassin Sédimentaire de Kribi-Campo et la bordure nord-ouest du Craton du Congo. Doctorat PhD Thèse, Université de Yaoundé I, Yaoundé, 120 p.
[9]
Koumetio, F., Njomo, D., Tatchum, C.N., Tokam, K.A.P., Tabod, C.T. and Manguelle-Di- coum, E. (2014) Interpretation of Gravity Anomalies by Multi-Scale Evaluation of Maxima of Gradients and 3D Modelling in Bipindi Region (South-West Cameroon). International Journal of Geosciences, 5, 1415-1425. http://dx.doi.org/10.4236/ijg.2014.512115
[10]
Koumetio, F., Manguelle-Dicoum, E., Ndougsa M.T. and Tabod, C.T. (2001) Gravity Study of the Faulting Tectonics around the Western Frontier of the Congo Craton in the Kribi Region (Cameroon). Journal de la Société Géosciences du Cameroun, 1, 62-63.
[11]
Shandini, Y.N., Tadjou, J.M., Tabod, C.T. and Fairhead, J.D. (2010) Gravity Data Interpretation in the Northern Edge of the Congo Craton, South-Cameroon. Anuário do Instituto de Geociências, 33, 73-82.
[12]
Shandini, Y. and Tadjou, J.M. (2012) Interpreting Gravity Anomaly in South Cameroon, Central Africa. Earth Sciences Research Journal, 16, 5-9.
[13]
Minyem, D. and Nedelec, A. (1990) Origin and Evolution of the Eseka Gneisses (Cameroon) Archean TTG Reworked in the Panafrican Mobile Belt. 15th Colloquium of African Geology, 2, 21-24.
[14]
Ngoumou, P.C., Ndougsa Mbarga, T., Assembe, S.P. and Kofane, T.C. (2014) Evidence of Iron Mineralization Channels in the Messondo Area (Centre Cameroon) Using Geoelectrical (DC & IP) Methods: A Case Study. International Journal of Geosciences, 5, 346-361. http://dx.doi.org/10.4236/ijg.2014.53034
[15]
Tchameni, R., Mezger, K., Nsifa, E.N. and Pouclet, A. (2001) Crustal Origin of Early Proterozoic Syenites in the Congo Craton (Ntem Complex), South Cameroon. Lithos, 57, 23-42. http://dx.doi.org/10.1016/S0024-4937(00)00072-4
[16]
Rosendahl, B.R. and Groschel-Becker, H. (1999) Deep Seismic Structure of the Continental Margin in the Gulf of Guinea: A Summary Report. In: Cameron, N.R., Bate, R.H. and Clure, V.S., Eds., The Oil and Gas Habitats of the South Atlantic, The Geological Society, London, 75-83. http://dx.doi.org/10.1144/gsl.sp.1999.153.01.05
[17]
Burke, K. (1969) Seismic Areas of the Guinea Coast Where Atlantic Fracture Zone Reach Africa. Nature, 222, 655-657. http://dx.doi.org/10.1038/222655b0
[18]
Perez-Diaz, L. and Eagles, G. (2014) Constraining South Atlantic Growth with Seafloor Spreading Data. Tectonics, 33, 1848-1873. http://dx.doi.org/10.1002/2014TC003644
[19]
Nsifa, E.N. (2005) Magmatisme et évolution géodynamique de l’Archéen au Protérozo?que de la bordure nord-ouest du craton du Congo (complexe du Ntem) au Sud-Ouest Cameroun. Doctoratd’Etat Thèse, Université de Yaoundé I, Yaoundé, 248 p.
[20]
Collignon, F. (1968) Gravimétrie et Reconnaissance de la Ré- publique Fédérale du Cameroun. ORSTOM, Paris, 35.
[21]
Fairhead, J.D. andOkereke, C.S. (1988) Depths to Major Density Contrasts beneath the West-African Rift System in Nigeria and Cameroon Based on the Spectral Analysis of Gravity Data. Journal of African Earth Sciences, 7, 769-777. http://dx.doi.org/10.1016/0899-5362(88)90018-8
[22]
Anderson, E.D. (2013) Aeromagnetic Signatures of the Geology in Mineral Resources near the Pebble Porphyric Cu-Au-Mo Deposit, Southwest Alaska. PhD Thesis, Colorado School of Mines, Golden, 112.
[23]
Biyiha-Kelaba, W., Ndougsa-Mbarga, T., Yene-Atangana, J.Q., Ngoumou, P.C. and Tabod, C.T. (2013) 2.5D Models Derived from the Magnetic Anomalies Obtained by Upwards Continuation in the Mimbi Area, Southern Cameroon. Journal of Earth Sciences and Geotechnical Engineering, 3, 175-199.
[24]
Teskey, D.J. and Hood, P.J. (1991) The Canadian aeromagnetic Database: Evolution and Applications to the Definition of Major Crustal Boundaries. Tectonophysics, 192, 41-51. http://dx.doi.org/10.1016/0040-1951(91)90245-N
[25]
Grant, F.S. and West, G.F. (1965) Interpretation Theory in Applied Geophysics. McGraw-Hill Book Co., New York, 583 p.
[26]
Reeves, C. (2005) Aeromagnetic Surveys: Principles, Practice and Interpretation. Earth- works, Washington DC, 155 p.
[27]
Blakely, R.J. (1996) Potential Theory Applied in Gravity and Magnetic Application. Reprinted Edition, Cambridge University Press, Cambridge, 441 p.
[28]
Milligan, P.R. and Gunn, P.J. (1997) Enhancement and Presentation of Airborne Geophysical Data. Journal of Australian Geology & Geophysics, 17, 63-75.
[29]
Cordell, L. and Grauch, V.J.S. (1985) Mapping Basement Magnetization Zones from Aeromagnetic Data in the San Juan Basin, New Mexico. In: Hinze, W.J., Ed., The Utility of Regional Gravity and Magnetic Anomaly Maps, Society of Exploration Geophysicists, 181-197. http://dx.doi.org/10.1190/1.0931830346.ch16
[30]
Noutchogwe, T.C., Koumetio, F. and Manguelle-Dicoum, E. (2010) Structural Features of South-Adamawa (Cameroon) Inferred from Magnetic Anomalies: Hydrogeological Implications. Comptes Rendus Geoscience, 342, 467-474. http://dx.doi.org/10.1016/j.crte.2010.03.004
[31]
Mohammad, A. (2014) Estimating the Hidden Gravity Lineaments Depths by Using Special Function Method and Comparing Them with the Earthquake Focal Depths: A Case Study of Gujarat Province. Geodynamics Research International Bulletin, 56-62.
[32]
Phillips, J.D. (2000) Locating Magnetic Contacts: A Comparison of the Horizontal Gradient, Analytic Signal, and Local Wavenumber Methods. Society of Exploration Geophysicists, Abstracts with Programs, Calagry.
[33]
Blakely, R.J. and Simpson, R.W. (1986) Approximating Edges of Source Bodies from Magnetic or Gravity Anomalies. Geophysics, 51, 1494-1498. http://dx.doi.org/10.1190/1.1442197
[34]
Saad, B. and Taoufik, M. (2006) Horizontal Gradient Signature of Morocco Bouguer Anomaly. Theoria, 15, 25-31.
[35]
Thompson, D.T. (1982) EULDPH—A New Technique for Making Computer Assisted Depth Estimates from Magnetic Data. Geophysics, 47, 31-37. http://dx.doi.org/10.1190/1.1441278
[36]
Reid, A.B., Allsop, J.M., Granser, H., Millet, A.J. and Somerton, I.W. (1990) Magnetic Interpretation in Three Dimensions Using Euler Deconvolution. Geophysics, 55, 80-91. http://dx.doi.org/10.1190/1.1442774
[37]
Reid, A.B. and Fitzgerald, D.J. (2005) Hybrid Euler Magnetic Basement Depth Estimation: Bishop 3D Tests. In: SEG Technical Program Expanded Abstracts, 671-674. http://dx.doi.org/10.1190/1.2144412
[38]
Foulger, G.R. and Pierce, C. (2007) Geophysical Methods in Geology. Teaching Handbook, University of Durham, Durham, 78 p.
[39]
Cordell, L. (1979) Gravimetric Expression of Graben Faulting in Santa Fe Country and the Espanola Basin, New Mexico. In: Ingersoll, R.V., Ed., Guidebook to Santa Fe Country, New Mexico Geological Society, Socorro, 59-64.
[40]
Archibald, N.J., Gow, P. and Boschetti, F. (1999) Multiscale Edge Analysis of Potential Field Data Exploration. Geophysics, 30, 38-44.
[41]
Murphy, F.C. (2008) Architecture: Worms and What They Can Show. New Perspectives: The Foundations and Future of Australian Exploration. Pmd*CRC Conference, Geoscience Australia Record, Perth, 11-12 June 2008, 45-51.
[42]
Holden, D., Archibald, N., Boschetti, F. and Jessell, M. (2001) Inferring Geological Structures Using Wavelet-Based Multiscale Edge Analysis and Forward Models. Exploration Geophysics, 31, 617-621. http://dx.doi.org/10.1071/EG00617
[43]
Reid, A.B. (2003) Short Note: Euler Magnetic Structural Index of a Thin Bed Fault. Geophysics, 68, 1255-1256. http://dx.doi.org/10.1190/1.1598117
[44]
Silva, J.B.C. and Barbosa, V.C.F. (2003) Euler Deconvolution: Theoretical Basis for Automatically Selecting Good Solutions. Geophysics, 68, 1962-1968. http://dx.doi.org/10.1190/1.1635050
[45]
Stavrev, P.Y. (1997) Euler Deconvolution Using Differential Similarity Transformations of Gravity or Magnetic Anomalies. Geophysical Prospecting, 45, 207-246. http://dx.doi.org/10.1046/j.1365-2478.1997.00331.x
[46]
Marson, I. and Klingele, E.E. (1993) Advantages of Using the Vertical Gradient of Gravity for 3-D Interpretation. Geophysics, 58, 1588-1595. http://dx.doi.org/10.1190/1.1443374
[47]
Fairhead, J.D., Bennet, K.J., Gordon, D.R.H. and Huang, D. (1994) Euler: Beyond the “Black Box”. In: SEG Technical Program Expanded Abstracts, 422-424. http://dx.doi.org/10.1190/1.1932113
[48]
Boukeke, D.B. (1994) Structures Crustales d’Afrique Centrale Déduites des Anomalies Gravimétriques et Magnétiques: Le Domaine Précambrien de la République Centrafricaine et du Sud Cameroun. PhD Thesis, Université de Paris Sud, Paris, 263 p.
[49]
Basseka, C.A., Shandini, Y. and Tadjou, J.M. (2011) Subsurface Structural Mapping Using Gravity Data of the Northern Edge of the Congo Craton, South Cameroon. Geofizika, 28, 229-245.
[50]
Manguelle-Dicoum, E., Bokossah, A.S. and Kwende-Mbanwi, T.E. (1992) Geophysical Evidence for a Major Precambrian Schist-Granite Boundary in Southern Cameroon. Tectonophysics, 205, 437-446. http://dx.doi.org/10.1016/0040-1951(92)90447-E
[51]
FeumoeSiyapdje, A.N., NdougsaMbarga, T., Manguelle-Dicoum, E. and Fairhead, J.D. (2012) Delineation of Tectonic Lineaments Using Aeromagnetic Data for the South-East Cameroon Area. Geofizika, 29, 175-192.
[52]
Ndougsa-Mbarga, T., FeumoeSiyapdje, A.N., Manguelle-Dicoum, E. and Fairhead, J.D. (2012) Aeromagnetic Data Interpretation to Locate Buried Faults in South-East Cameroon. Geophysica, 48, 49-63.
