Quantification of Strain of the Pan-African in Mvog-Betsi Area (Yaoundé Group, Cameroon)
International Journal of Environmental Monitoring and Analysis
Volume 6, Issue 2, April 2018, Pages: 40-46
Received: Mar. 30, 2018; Accepted: Apr. 24, 2018; Published: May 25, 2018
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Authors
Jean Engelbert Mpesse, Department of Earth Sciences, Faculty of Sciences, University of Douala, Douala, Cameroon
Joseph Martial Akame, Department of Earth Sciences, Faculty of Sciences, University of Yaoundé I, Yaoundé, Cameroon
Eric José Messi Ottou, Department of Earth Sciences, Faculty of Sciences, University of Yaoundé I, Yaoundé, Cameroon
Bernard Njom, Department of Earth Sciences, Faculty of Sciences, University of Yaoundé I, Yaoundé, Cameroon
Sébastien Owona, Department of Earth Sciences, Faculty of Sciences, University of Douala, Douala, Cameroon
Jean Bosco Olinga, Institut of Geological and Mining Research, Yaounde, Cameroon
Justin Lissom, Department of Earth Sciences, Faculty of Sciences, University of Douala, Douala, Cameroon
Joseph Mvondo Ondoa, Department of Earth Sciences, Faculty of Sciences, University of Yaoundé I, Yaoundé, Cameroon
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Abstract
The ductile deformation in the paragneissic bed of Mvog-Betsi in the north-eastern part of Yaounde (Cameroon) appears to be intensive and may be traduced by a high shear rate (more than 10%). Some marker subjects that may quantify this strain are observed. Those are elliptical quartz and feldspar, and folds. The study of elliptical markers shows their preferential orientation. The initial rate Ri of the markers before the strain approaches 3.76, and the harmonic value of Rf is between 1.51 and 1.71. Main orientation Øf of strain’s ellipse from the direction of stretching in actual position is situated between -10 and -19. The strain’s rate RS is comprised between 1.1 and 1.7. The orientation ØS of the strain’s ellipse is situated between N10E and N20E. The rate of shortening varies between 20% and 75%.
Keywords
Strain, Method, Rate of Deformation, Yaoundé Group, Cameroon
To cite this article
Jean Engelbert Mpesse, Joseph Martial Akame, Eric José Messi Ottou, Bernard Njom, Sébastien Owona, Jean Bosco Olinga, Justin Lissom, Joseph Mvondo Ondoa, Quantification of Strain of the Pan-African in Mvog-Betsi Area (Yaoundé Group, Cameroon), International Journal of Environmental Monitoring and Analysis. Vol. 6, No. 2, 2018, pp. 40-46. doi: 10.11648/j.ijema.20180602.11
Copyright
Copyright © 2018 Authors retain the copyright of this article.
This article is an open access article distributed under the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
References
[1]
Ball, E, Bard, J., P., Soba, D., 1984. Tectonique tangentielle dans la catazone du Cameroun: Les gneiss de Yaoundé. J. Afr. Earth Sci. Vol. n°2, P. 91-95.
[2]
Nzenti J., P: 1987. Pétrogénèse des migmatites de Yaoundé (Cameroun): élément pour un modèle géodynamique de la chaîne Pan-africaine Nord-équatoriale. Thèse de l’Université de Nancy I. 147 p.
[3]
Mpesse, J., E., 1999. Contribution à l’étude pétrostructurale des formations métamorphiques de la région de Yaoundé et définition de la géométrie de sa tectonique tangentielle. Thèse doct. 3è cycle, Univ. de Yaoundé I, 148.
[4]
Mpesse J. E., Lissom, J., Mvondo Ondoa, J., Njom B., Frisch Wolfgan, (2002). Plis en fourreau dans les migmatites panafricaines de Yaoundé preuve d’une déformation chevauchante progressive. Sci. Technol. Dev. vol. 9. n01, 37-43.
[5]
Jegouzo, 1984. Déformation chevauchante et cisaillante dans la zone mobile d’Afrique centrale au Cameroun. Coll. Chevauchement et Deformation, Toulouse.
[6]
Nédélec, A., Macaudière, J., Nzenti, J. P., Barbey, P., 1986. Evolution structurale et métamorphique des schistes de Mbalmayo (Cameroun). Implications pour la structure de la zone mobile panafricaine d'Afrique Centrale, au contact du craton du Congo. Comptes Rendus de l'Académie des Sciences, Paris 303, 75–80.
[7]
Maurizot P, Abessolo A, Feybesse A, Johan JL, Lecompte P (1986). Etude et prospection minière au Sud Ouest Cameroun. Synthèse des travaux de 1978-1985. Rap. BRGM, 85, CNRS 066, Orléans: 274.
[8]
Nzenti JP, Barbey P, Macaudiere J, Soba D (1988). Origin and evolution of the late Precambrian high-grade Yaounde gneisses (Cameroon). Precamb. Res. 38:91-109.
[9]
Minyem, D., 1994. Contribution a` l’étude de l’évolution métamorphique et structurale du secteur Eséka-Makak (Cameroun, Département du Nyong et Kelle, Province du Centre). The` se Doc. 3e Cycle, Universite´ Yaounde´ I, 166 p.
[10]
Ngako, V., Affaton, P., Nnangue, J,. M; and Njanko, Th. 2003. Pan-African tectonic evolution in central and southern Cameroon: transpression and transtension during sinistral shear movements. Journal of African Earth Sciences, 36, 207-214.
[11]
Mvondo Ondoa, J., and Essono, J., 2007. Tectonic evolution of the Yaoundé segment of the Neoproterozoic Orgogenic Belt in South Cameroon (central Africa). Canadian Journal of Earth Sciences, 44, 443-444.
[12]
Pengcheng Fu and Yannis F. Dafalias 2012. Quantification of large and localized deformation in granular materials. Elsevier, Volume 49, Pages 1741–1752.
[13]
Ramsay, J., G., 1967. Folding and fracturing of rocks. M. C. Graw-Hill, New-York. 568p.
[14]
Dunnet, D., 1969. A technique of finite strain analysis using elliptical markers. Tectonophysics, V. 7, n 2, P. 117-136.
[15]
Dunnet, D. and Siddans, A., B., 1971. Non-random sedimentary fabrics and their modification by strain. Tectonophysics, 12, 307-325.
[16]
Lisle, R., J., 1979. Strain analysis using deformed pebble shape: the influence of initial pebble shape. Tectonophysics, 60: 263-277; Amsterdam.
[17]
Peach, C. J. & Lisle, R. J. 1979. A Fortran IV program for the analysis of tectonic strain using deformed elliptical markers. Comput. Geosci. 5, 325-334.
[18]
Ratschbacher, L., Meschede, M., Spener, B., and Pfänder, J. 1994. Computer-techniken und andwendungen: Eine Computer-programmbibliothek zur quantitativen Strukturanalyse. Tubinger Geowissenschaflitche Arbeiten (TGA). Reihe A, Band 21, 73.
[19]
Lisle, R., J., 1985. Geological strain analysis: a manual for the Rf/Ø technic. Pergamon Press, Oxford, 99p.
[20]
De Paor, D., G., 1988. Rf/Øf strain analysis using an orientation net. J. of Structural geology, 10, pp. 323 to 333, Oxford.
[21]
Olinga, J., B., Mpesse, J., E., Minyem, D., Ngako, V., Ndougsa Mbarga, T. and Ekodeck, G., E., 2010. The Awaé–Ayos strike-slip shear zones (southern Cameroon): geometry, kinematics and significance in the late pan-african tectonics, Yaoundé. N. Jb. Geol. Paläont. Abh. 257/1, 1–11.
[22]
Mvondo; H. Den Brok, S. W. J., Mvondo Ondoa, J., 2003. Evidence for symmetric extension and exhumation of Yaoundé nappe (Pan-African fold belt, Cameroon). Journal of African Earth Sciences 36, 215-231.
[23]
Castaing C, Feybesse JL, Thiéblemont D, Triboulet C, Chèvremont P (1994). Palaeogeographical reconstructions of the Pan-African/Brasiliano orogen: closure of an oceanic domain or intracontinental convergence between major blocks? Precamb. Res., 69 (1-4): 327-344.
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