| Broom-Fendley, Sam, Brady, Aoife E., Horstwood, Matthew S.A., Woolley, Alan R., Mtegha, James, Wall, Frances, Dawes, Will, Gunn, Gus (2017) Geology, geochemistry and geochronology of the Songwe Hill carbonatite, Malawi. Journal of African Earth Sciences, 134. 10-23 doi:10.1016/j.jafrearsci.2017.05.020 | Journal (article/letter/editorial) | km) and slightly older (134.6 ± 4.4 Ma) Mauze nepheline syenite and then evolved through three different...level of emplacement into the crust. This shallow intrusion level acted as a reservoir for multiple stages...proximity and similar age of the large Mauze nepheline syenite suggests it may have acted as a heat source...Introduction Since the discovery of carbonatites in Africa (Dixey et al., 1937), many of the carbonatite complexes...these new data, we discuss the evolution of this intrusion in the context of other intrusions in the Chilwa | | | Report (chapter) | (some with nepheline syenite and nephelinite), large complexes of nepheline syenite and syenite, and plutons...plutons of peralkaline syenite, quartz syenite and granite, together with dykes compositionally equivalent...present: (1) syenitequartz syenite-granite, (2) nepheline syenite-syenite and (3) nephelinite-carbonatitenepheline...nephelinite-carbonatitenepheline syenite. It has not proved possible to relate these series to a single parental magma...traced southwards through Mozambique into South Africa, with the change in structural style corresponding | | | Report (volume) | Island 269 FITTON, J. G. The Cameroon line, West Africa: a comparison between oceanic and continental alkaline... LARSEN, L. M. & SORENSEN, H. The Ilimaussaq intrusion--progressive crystallization and formation of...of the classic alkaline provinces, such as East Africa, southern Greenland and the Kola Peninsula, are...alumina with respect to alkalis and will have nepheline and/or acmite in their norms. In practice the...silica-deficient but are rarely alkali-rich. True (nepheline-normative) alkali basalts grade into hypersthene-normative |
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