IJG  Vol.5 No.1 , January 2014
Carbonate Enrichment in Volcanic Debris and Its Relationship with Carbonate Dissolution Signatures of Springs in the Sabga-Bamessing, North West, Cameroon
ABSTRACT

Sabga-Bamessing is a part of the Bamenda Mountains, an extinct volcanic center of the West Cameroon Highlands along the Cameroon Volcanic Line (CVL). The pristine volcanic rocks of the Sabga area are alkali mafic to felsic (basanites, phonolites, trachytes and rhyolites). Some weathered sections of a heterolithologic debris flow with a suppositious primary chemistry of the original volcanic rocks prior to weathering have shown significant calcium carbonate enrichment. CaO and LOI values of up 61.31% and 41.72% respectively show corresponding enrichment of 16.54 and 10.88, when compared with average fresh volcanic rocks. Na+ normalized molar ratios computed from the chemistry of springs and rivers show carbonate dissolution signature which is contrary to silicate dissolution expected in acid volcanic rocks. Saturation indices (SI) calculated with PHREEQC reveal that brackish to saline springs are supersaturated with Calcite (CaCO3), Aragonite (CaCO3), Dolomite (CaMg(CO3)2 and Hydroxyl apatite (Ca5(PO4)3OH). Recharging contributions to spring water chemistry deviate from those produced by rock weathering, precipitation and evaporation/crystallization. An enrichment process is therefore predicted as a recharging contributor to water chemistry.


Cite this paper
Verla, R. , Mboudou, G. , Njoh, O. , Ngoran, G. and Afahnwie, A. (2014) Carbonate Enrichment in Volcanic Debris and Its Relationship with Carbonate Dissolution Signatures of Springs in the Sabga-Bamessing, North West, Cameroon. International Journal of Geosciences, 5, 107-121. doi: 10.4236/ijg.2014.51012.
References
[1]   E. Njonfang, A. Nono, P. Kamgang, V. Ngako and M. F. Tchoua, “Cameroon Line Alkaline Magmatism (Central Africa): A Reappraisal,” The Geological Society of America Special paper, Vol. 478, 2011, pp. 173-189.
http://dx.doi.org/10.1130/2011.2478(09)

[2]   B. Deruelle, I. Ngounouno and D. Demaiffe, “The ‘Cameroon Hot Line’ (CHL): A Unique Example of Active Alkaline Intraplate Structure in Both Oceanic and Continental Lithospheres,” Comptes Rendus Geoscience, Vol. 339, No. 9, 2007, pp. 589-600.
http://dx.doi.org/10.1016/j.crte.2007.07.007

[3]   J. J. Fitton, “The Benue Trough and the Cameroon Line— A Migrating Rift System in West Africa,” Earth and Planetary Science Letters, Vol. 51, No. 1, 1980, pp. 132-138. http://dx.doi.org/10.1016/0012-821X(80)90261-7

[4]   D. C. Lee, A. N. Halliday, J. J. Fitton and G. Poli, “Isotopic Variations with Distance and Time in the Volcanic Islands of the Cameroon Line: Evidence for a Mantle Plume Origin,” Earth Planetary Science Letters, Vol. 123, No. 1-3, 1994, pp. 119-138
http://dx.doi.org/10.1016/0012-821X(80)90261-7

[5]   J. B. Meyers, B. R. Rosendahl, C. G. Harrison and Z. D. Ding, “Deep-Imaging Seismic and Gravity Results from the Offshore Cameroon Volcanic Line, and Speculation of African Hotlines,” Tectonophysics, Vol. 284, No. 1-2, 1998, pp. 31-63.
http://dx.doi.org/10.1016/S0040-1951(97)00173-X

[6]   T. Yokoyama, F. Aka, M. Kusakabe and E. Nakamura, “Plume-Lithosphere Interaction Beneath Mt. Cameroon Volcano, West Africa: Constraints From 238U-230Th-226Ra and Sr-Nd-Pb Isotopes Systematics,” Geochimica et Cosmochimica Acta, Vol. 71, No. 7, 2007, pp. 1835-1854.
http://dx.doi.org/10.1016/j.gca.2007.01.010

[7]   C. E. Suh, R. S. Sparks, J. J. Fitton, S. N. Ayonghe, C. Annen and R. Nana, “The 1999 and 2000 Eruptions of Mount Cameroon: Eruption Behaviour and Petrochemistry of Lava,” Bulletin of Volcanology, Vol. 65, No. 4, 2003, pp. 267-283.
http://dx.doi.org/10.1007/s00445-002-0257-7

[8]   M. Gountie Dedzo, A. Nedelec, T. Nono, T. Njanko, E. Font and P. Kamgang, “Magnetic Fabrics of the Miocene Ignimbrites from West-Cameroon: Implications for Pyroclastic Flow Source and Sedimentation,” Journal of Volcanology and Geothermal Research, Vol. 203, No. 3, 2011, pp. 113-132.

[9]   G. Bwele, “L’encyclopédie de la République unie du Cameroun,” Nouvelles éditions Africaines, Abidjan, 1981.

[10]   A. S. Neba, “Modern Geography of the Republic of Cameroon,” Neba Publishers, Camdem, 1987.

[11]   P. Kamgang, E. Njonfang, A. Nono, M. Gountie Dedzo and M. F. Tchoua, “Petrogenesis of a Silicic Magma System: Geochemical Evidence from Bamenda Mountains, NW Cameroon, Cameroon Volcanic Line,” Journal of African Earth Sciences, Vol. 58, No. 2, 2010, pp. 285-304.
http://dx.doi.org/10.1016/j.jafrearsci.2010.03.008

[12]   P. Kamgang, E. Njonfang, G. Chazot and F. Tchoua, “Géochimie et Géochronologie des Laves Felsiques des Monts Bamenda (Ligne Volcanique du Cameroun),” Comptes Rendus Géoscience, Vol. 339, No. 10, 2007, pp. 659-666. http://dx.doi.org/10.1016/j.crte.2007.07.011

[13]   P. Kamgang, G. Chazot, E. Njonfang and F. Tchoua, “Geochemistry and Geochronology of Mafic Rocks from Bamenda Mountains (Cameroon): Source Composition and Crustal Contamination along the Cameroon Volcanic Line,” Comptes Rendus Geoscience, Vol. 340, No. 12, 2008, pp. 850-857.
http://dx.doi.org/10.1016/j.crte.2008.08.008

[14]   I. K. Njilah, H. N. Ajonina, K. V. Kamgang and M. Tchindjang, “K-Ar Ages, Mineralogy, Major and Trace Element Geochemistry of the Tertiary-Quaternary Lavas from the Ndu Volcanic Ridge N. W. Cameroon,” African Journal of Science and Technology (AJST), Vol. 5, No. 1, 2004, pp. 47 -56.

[15]   A. Marzoli, P. R. Renne, E. M. Piccirillo, F. Castorina, G. Bellieni and A. J. Melfi, “Silicic Magmas from the Continental Cameroon Volcanic Line (Oku, Bambouto and Ngaoundere): 40Ar/39Ar dates, petrology, Sr-Nd-O Isotopes and Their Petrogenetic Significance,” Contributions to Mineralogy and Petrology, Vol. 135, No. 2-3, 1999, pp. 133-150.
http://dx.doi.org/10.1007/s004100050502

[16]   R. Salminen, T. Tarvainen, A. Demetriades, M. Duris, F. Fordyce and V. Gregorauskiene, “FOREGS Geochemical Mapping Field Manual,” Geological Survey of Finland guide, Rovaniemi, 1998.

[17]   D. L. Parkhurst and C. A. Appelo, “User’s Guide to PHREEQC (Version 2)—A Computer Program for Speciation, Batch-Reaction, One-Dimensional Transport and Inverse Geochemical Calculations,” US Geological Survey Water-Resources Investigations, Report 99-4259, 1999, p. 310.

[18]   A. Streckeisen, “To Each Plutonic Rock Its Proper Name,” Earth Science Reviews, Vol. 12, No. 1, 1976, pp. 1-33.
http://dx.doi.org/10.1016/0012-8252(76)90052-0

[19]   A. Streckeisen, “IUGS Subcommission on the Systematics of Igneous Rocks Classification and Nomenclature of Volcanic Rocks, Lamprophyres, Carbonatites and Melilitic Rocks. Recommendations and Suggestions,” Neues Jahrbuch für Mineralogie Stuttgart, Vol. 134, 1978, pp. 1-14.

[20]   A. Streckeisen, “Classification and Nomenclature of Volcanic Rocks, Lamprophyres, Carbonatites and Melilitic Rocks: Recommendations and Suggestions of the IUGS Sub Commission on the Systematics of Igneous Rocks: Geology,” The Geological Society of America, Boulder, Vol. 7, No. 7, 1979, pp. 331-335.

[21]   R. Schmid, “Descriptive Nomenclature and Classification of Pyroclastic Deposits and Frgments: Recommendations of the IUGS Subcommission on the Systematics of Igneous Rocks: Geology,” The Geological Society of America, Boulder, Vol. 9, No. 1, 1981, pp. 41-43.

[22]   M. J. Le Bas and L. R. W. Maitre, A. Streckeisen and B. Zanettin, “A Chemical Classification of Volcanic Rocks Based on Total Alkali-Silica Diagram,” Journal of Petrology, Vol. 27, No. 3, 1986, pp. 745-750.
http://dx.doi.org/10.1093/petrology/27.3.745

[23]   Beeson, “Alkali Olivine Basalt, Sample KLPA-1, East Molokai Volcanoe Hawaii,” In: R. A. Loren, Ed., Petrolgy: The Study of Igneous, Sedimentary and Metamorphic Rocks, 2nd Edition, McGraw-Hill, New York, 2002, pp. 102-103.

[24]   Coats, “Circle Creek Rhyolite, Sample 60NC145, Elko Country, Nevada,” In: R. A. Loren, Ed., Petrology: The Study of Igneous, Sedimentary and Metamorphic Rocks, 2nd Edition, McGraw-Hill, New York, pp. 126-127.

[25]   W. Cross, J. P. Iddings, L. V. Pirsson and L. V. Washington, (1903): “Quantitative Classification of Igneous Rocks,” University of Chicago Press, Chicago, 1903.

[26]   C. H. Kelsey, “Calculation of CIPW Norm,” Mineralogical Magazine, Vol. 34, 1965, pp. 276-282.
http://dx.doi.org/10.1007/s004100050502

[27]   E. P. Thornton and O. E. Tuttle, “Chemistry of Igneous Rocks-Differentiation Index,” American Journal of Science, Vol. 258, No. 9, 1960, pp. 664-684.
http://dx.doi.org/10.2475/ajs.258.9.664

[28]   H. A. Gorrell, “Classification of Formation Waters Based on Sodium Chloride Content,” American Association of Petroleum Geologists Bulletin,” Vol. 42, No. 10, 1958, pp. 2513.

[29]   A. M. Piper, “A Graphic Procedure in the Geochemical Interpretation of Water Analyses,” Transactions, American Geophysical Union, Vol. 25, No. 6, 1944, pp. 914-923. http://dx.doi.org/10.1029/TR025i006p00914

[30]   G. Z. Tanyileke, M. Kusakabe and W. C. Evans, “Chemical and Isotopic Characteristics of Fluids along the Cameroon Volcanic Line, Cameroon,” Journal of African Earth Science, Vol. 22, No. 4, 1996, pp. 433-44.
http://dx.doi.org/10.1016/0899-5362(96)00025-5

[31]   C. Dessert, B. Dupre, J. Gaillardet, M. Francois and C. Allegre, “Basalt Weathering Laws and the Impact of Basalt Weathering,” Chemical Geology, Vol. 202, No. 3-4, 2003, pp. 257-273.
http://dx.doi.org/10.1016/j.chemgeo.2002.10.001

[32]   R. J. Gibbs, “Mechanisms Controlling World Water Chemistry,” Science, Vol. 17, No. 8, 1990, pp. 1088-1090.

[33]   S. M. Yidana, B. Banoeng-Yakubo and P. A. Sakyi, “Identifying Key Processes in the Hydrochemistry of a Basin through the Combined Use of Factor and Regression Models,” Journal of Earth System Science, Vol. 121, No. 2, 2012, pp. 491-507.
http://dx.doi.org/10.1007/s12040-012-0163-0

[34]   A. L. Marechal, “Géologie et Giochimie des Sources Thermo-minérales du Cameroun,” Travaux et Documents de L’orstom N0 59, Orstom, Paris, 1976.

[35]   N. S. Davis and J. R. De Wiest, “Hydrogeology,” Wiley & Sons Inc., New York, 1966.

[36]   H. Shinohara, W. Giggenbach, M. Kusakabe and T. Ohba, “Formation of Acid Volcanic Brines through Interaction of Magmatic Gases,” Geochimica et Cosmochimica Acta, Vol. 67, No. 18, 2003, p. 433.

[37]   E. J. Lynn, “Geographic Information Systems in Water-Resources Engineering,” CRC Press (Taylor & Francis Group), Boca Raton, 2009.

[38]   A. Abdul-Rahman and M. Pilouk, “Spatial Data Modelling for 3D GIS,” Springer, New York, 2008.

[39]   A. P. Gretchen, “GIS Cartography: A Guide to Effective Map Design,” CRC Press (Taylor & Francis Group), Boca Raton, 2009.

 
 
Top