AASCIT - Journal - All Issues

American Journal of Earth Science and Engineering

The Journal

Indexing

Manuscript Information

Petrology of Kaersutite Megacryst-Bearing Benmoreites from the Tignere Volcanic Domain (Adamawa Plateau, Cameroon)

American Journal of Earth Science and Engineering
Vol.1 , No. 3, Publication Date: Apr. 27, 2018, Page: 150-165

966 Views Since April 27, 2018, 487 Downloads Since Apr. 27, 2018

Paper in PDF (8560K)

Follow on

Authors

[1]	Isaac Bertrand Gbambié Mbowou, Department of Mines and Geology, University of Ngaoundere, Meiganga, Cameroon.
[2]	Nilson Francisquini Botelho, Geosciences Institute, University of Brasilia (UnB) Asa Norte, Brasilia, Brazil.
[3]	Ismaïla Ngounouno, Department of Mines and Geology, University of Ngaoundere, Meiganga, Cameroon.

Abstract

Kaersutite megacryst-bearing benmoreites from the Tignere volcanic domain belong to the Adamawa Plateau (Cameroon). These rocks are characterized by a porphyritic texture and consist of plagioclase, alkali feldspar, amphibole, clinopyroxene, biotite, Fe-Ti oxides and apatite phenocrysts with amphibole megacrysts. Benmoreites display negative P, Ti and Rb anomalies with relatively low ⁸⁷Sr/⁸⁶Sr ratios (0.7037). Kaersutite megacrysts (mg#: 0.67) and phenocrysts (mg#: 0.66) are relatively similar in composition and seem to be generated from the same magma and under similar thermobarometric conditions as evidenced by mineral chemistry. Benmoreites from Tignere are to be regarded as the product of fractional crystallization processes from basaltic lava.

Keywords

Benmoreite, Fractional Crystallization, Tignere Volcanic Domain, Adamawa Plateau

Reference

[01]	Nono A, Déruelle B, Demaiffe D, Kambou R (1994) Tchabal Nganha volcano in Adamawa (Cameroon): petrology of a continental alkaline lava series. J Volcano Geotherm Res 60: 147–178 doi: 10.1016/0377-0273(94) 90066-3.
[02]	Nkouandou OF, Ngounouno I, Déruelle B, Ohnenstetter D, Montigny R Demaiffe D (2008) Petrology of the Mio-Pliocene volcanism to the North and East of Ngaoundéré (Adamawa, Cameroon). C R Geos 340: 28–37 doi: 10.1016/jcrte.2007.10.012.
[03]	Mbowou GIB, Ngounouno I, Deruelle B (2010) Pétrologie du volcanisme bimodal du Djinga Tadorgal (Adamaoua, Cameroun). Rev. Cames. 11: 36–42.
[04]	Macdonald R, Belkin HE, Fitton JG, Rogers NW, Nejbert K, Tindle AG, Marshall AS (2008) The roles of fractional crystallization, magma mixing, crystal mush remobilization and volatilemelt interactions in the genesis of young basalt peralkaline rhyolite suite, the Greater Olkaria Volcanic Complex, Kenya Rift Valley. J Petrol 49: 1515–1547 doi: 10.1093/petrology/egn036.
[05]	Macdonald R (2012) Evolution of peralkaline silicic complexes: lessons from the extrusive rocks. Lithos 152: 11–22 doi: 10.1016/j.lithos.2012.01.014.
[06]	Peretyazhkoa IS, Savinaa EA, Karmanovb NS, Shcherbakova Yu D (2015) Genesis of mugearites and benmoreites of Nemrut Volcano, Eastern Turkey: Magma mixing and fractional crystallization of trachybasaltic melt. Petrology 23: 376–403.
[07]	Ngounouno I, Moreau C, Déruelle B, Demaiffe D, Montigny R (2001) Pétrologie du complexe alcalin sous-saturé de Kokoumi (nord du Cameroun). Bull Soc Géol France 172: 675–686.
[08]	Lissom J (1991) Etude pétrologique des laves alcalines du massif d’Oku: un ensemble volcanique de la Ligne du Cameroun. Thèse de Doctorat. Université Pierre et Marie Curie, Paris 6. Pp 1–205.
[09]	Clocchiatti R, Tanguy J (2002) Mégacristaux d'amphibole dans les laves de l'Etna (l'éruption de juillet-août 2001). 19ème Réunion des Sciences de la Terre, Nantes, France. Pp 1–94.
[10]	Borley GD, Suddady P, Scott P (1971) Some xenoliths from the Alkalic Rocks of Tenerife, Canari islands. Contrib Mineral Petrol 31: 102–114 doi: 10.1007/bf00373453.
[11]	Bédard JH (1988) Comparative amphibole chemistry of the Monteregian and Mountain alkaline suites, and the origin of amphibole megacrysts in alkali basalts and lamprophyres. Mineral Mag 52: 91–103.
[12]	Toteu SF, Penaye J, Van Schmus WR, Michard A (1994) Preliminary U–Pb and Sm–Nd geochronologic data on the North-Central Cameroon: contribution of an Archean and paleo-Proterozoic crust to the edification of an active domain of the Pan-African orogeny. C R Acad Sci Paris 319: 1519–1524.
[13]	Moreau C, Regnoult J-M, Déruelle B, Robineau B (1987) A new tectonic model for the Cameroon Line. Tectonophysics, 139: 317–334 doi: 10.1016/0040-1951(87)90206-x.
[14]	Penaye J, Toteu SF, Tchameni R, Van Schmus WR, Tchakounté J, Ganwa A, Minyem D, Nsifa EN (2004) The 2.1 Ga West Central African Belt in Cameroon: extension and evolution. J Afr Earth Sci 39: 159–164 doi: 10.1016/j.jafrearsci.2004.07.053.
[15]	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? Precambr Res 69: 327–344 doi: 10.1016/0301-9268(94)90095-7.
[16]	Toteu SF, Van Schmus RW, Penaye J, Michard A (2001) New U–Pb and Sm–Nd data from north-central Cameroon and its bearing on the pre-Pan-African history of central Africa. Precam Res 108: 45–73 doi: 10.1016/s0301-9268(00)00149-2.
[17]	Vicat JP, Ngounouno I, Pouclet A (2001) Existence de dykes doléritiques anciens à composition de tholéiites continentales au sein de la province alcaline de la ligne du Cameroun. Implication sur le contexte géodynamique. C R Acad Sci Paris 332: 243–249 doi: 10.1016/s1251-8050(01)01526-9.
[18]	Pouchou JL, Pichoir F (1991) Quantitative analysis of homogeneous or stratified microvolumes applying the model «PAP». In: Electron Probe Quantification, K. F. J., Heinrich, D. E., Newbury (Eds) Plenum Press, New York, 31–75.
[19]	Carignan J, Hild P, Mevelle G, Morel J, Yeghicheyan D (2001) Routine analyses, of trace elements in geological samples using flow injection and low pressure on liquid chromatography coupled to ICP-MS: a study of geochemical reference materials BR, DR-N, UB-N, AN-G and GH. Geostandards Newsletters 25: 187–198 doi: 10.1111/j.1751-908x.2001.tb00595.x.
[20]	Roeder PL, Emslie RF (1970) Olivine-liquid equilibrium. Contrib Mineral Petrol 29: 275–289 doi: 10.1007/bf00371276.
[21]	Morimoto A N and 8 co-authors (1988) Nomenclature of pyroxenes, IMA. Mineral Mag 52: 533–550.
[22]	Wass SY (1979) Multiple origins of clinopyroxenes in alkali basaltic rocks. Lithos 12: 115–132 doi: 10.1016/0024-4937(79)90043-4.
[23]	Avanzinelli R, Bindi L, Menchetti S, Conticelli S (2004) Crystallisation and genesis of peralkaline magmas from Pantelleria Volcano, Italy: an integrated petrological and crystal-chemical study. Lithos, 73: 41–69. doi: 10.1016/j.lithos.2003.10.007.
[24]	Kunzmann T (1999) The ænigmatite-rhönite mineral group. Eur. J. Mineral. 11: 743–756.
[25]	Deer WA., Howie Zussman J (1992). An Introduction to the rock-forming Minerals, 2nd ed, Pearson Prentice Hall, Harlow, 696pp.
[26]	Leake BE, Wooley AR, Birch WD, Gilbert MC, Grice JD, Hawthorne FC, Kato A, Kisch HJ, Krivovichev VG, Linthout K, Laird J, Mandarino J (1997) Nomenclature of Amphibole: Repport of the Subcommitee on Amphiboles of the International Association Commission on New Minerals and Mineral Names. Mineral Mag 61: 295–321.
[27]	McDonough WF, Sun SS (1995) The composition of the Earth. Chem Geol 120: 223–253 doi: 10.1016/0009-2541(94)00140-4.
[28]	Le Bas, MJ, Le Maitre RW, Streckeisen A, Zanettin B (1986). A chemical classiﬁcation of volcanic rocks based on the total alkali-silica diagram. J Petrol 27: 745–750. doi: 10.1093/petrology/27.3.745.
[29]	Le Maitre RW (2002) Igneous rocks: a classiﬁcation and glossary of terms: recommendations of the International Union of Geological Sciences, Sub- commission on the Systematics of Igneous Rocks. Cambridge University Press, Cambridge UK 236 pp.
[30]	Ellam RM, Hawkesworth CJ, Menzies MA, Rogers NV (1989) The volcanism of southern Italy: role of subduction and the relationship between potassic and sodic alkaline magmatism. J geophys Res 9: 4589-4601 doi: 10.1029/jb094ib04p04589.
[31]	Cox KG, Bell JD, Pankhurst RJ, (1979) In: The Interpretation of Igneous Rocks. George Allen & Unwin, London 450 pp.
[32]	Powell W, Zhang M, O’Reilly SY, Tiepolo M (2004) Mantle amphibole trace-element and isotopic signatures trace multiple metasomatic episodes in lithospheric mantle, Western Victoria, Australia. Lithos 75: 141–171. doi: 10.1016/j.lithos.2003.12.017.
[33]	Shaw CSJ, Eyzaguirre J (2000) Origin of megacrysts in the mafic alkaline lavas of West Eifel volcanic field, Germany. Lithos 50: 75-95 doi: 10.1016/s0024-4937(99)00048-1.
[34]	Mayer B, Jung S, Romer RL, Pfänder JA, Klügel A, Pack A, Gröner E (2014) Amphibole in alkaline basalts from intraplate settings: implications for the petrogenesis of alkaline lavas from the metasomatised lithospheric mantle Contrib Mineral Petrol 167: 989–810 doi: 10.1007/s00410-014-0989-3.
[35]	Witt-Eickschen G, Kaminsky W, Kramm U, Harte B (1998) The nature of young vein metasomatism in the lithosphere of the West Eifel (Germany): Geochemical and isotopic constraints from composite mantle xenoliths from the Meerfelder Maar. J Petrol 39: 155–185 doi: 10.1093/petroj/39.1.155.
[36]	Witt-Eickschen G, Seck HA, Mezger K, Eggins SM, Altherr R (2003) Lithospheric mantle evolution beneath the Eifel (Germany): Constraints from Sr-Nd-Pb isotopes and trace element abundances in spinel peridotite and pyroxenite xenoliths. J Petrol 44: 1077–1095 doi: 10.1093/petrology/44.6.1077.
[37]	Hawkesworth CJ, Gallagher K (1993) Mantle hotspots, plumes and regional tectonics as causes of intraplate magmatism. Terra Nova 5: 552–559 doi: 10.1111/j.1365-3121.1993.tb00304.x.
[38]	Conner AB (2000) The mineral kaersutite and its occurrences. Senior Thesis, The Ohio State University. Pp 1–12.
[39]	Ersoy Y, Helvacı C (2010) FC–AFC–FCA and mixing modeler: A Microsoft Excel spreadsheet program for modeling geochemical differentiation of magma by crystal fractionation, crustal assimilation and mixing. Computers & Geosciences 36: 383–390 doi: 10.1016/j.cageo.2009.06.007.
[40]	Hart SR, Blusztajn J, Dick HJB, Meyer PS, Muehlenbachs K (1999) The ﬁngerprint of seawater circulation in a 500-meter section of ocean crust gabbros. Geochimica et Cosmochimica Acta 63: 4059–4080 doi: 10.1016/s0016-7037(99)00309-9.