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A Reconsideration of Certain Aspects of the Rangwa and Ruri Carbonatite Complexes in Western Kenya

Published online by Cambridge University Press:  01 May 2009

G. J. H. McCall
Affiliation:
Dept. of Geology, The University of Western Australia, Nedlands, W., Australia.

Abstract

Dykes with melilite occur in the area peripheral to the Rangwa complex. A flow-lineated alvikite dyke situated in the area just outside the North Ruri complex contains calcitic pseudomorphs of phenocrysts, and it is suggested that the majority of these are after melilite. The significance of the observed restriction of melilitic dykes to the peripheral area of the complexes is considered in the light of the recognition of a gradational progression from kimberlite-alnöite dykes to beforsite and alvikite dykes at Alnö island and its environs in Sweden. The possibility that cauldron subsidence is involved in some of the Kenya complexes is considered.

Type
Articles
Copyright
Copyright © Cambridge University Press 1963

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References

REFREENCES

King, B. C., 1960. Alkaline rocks of southern and eastern Africa, Sci. Prog. 48, Nos. 191, 192, 193 (in three parts).Google Scholar
McCall, G. J. H., 1956. Alkaline and carbonatite ring complexes in the Kavirondo Rift Valley, Kenya. Proc. XXth Int. Geol. Congr. Mexico, Assoc. African Geol. Surveys Volume, pp. 327334 (Published 1959).Google Scholar
McCall, G. J. H., 1958. The geology of the Gwasi area. Geol. Surv. Kenya Rept., 45.Google Scholar
Pulfrey, W., 1953. A Kenya alnöite and associated skarns. J. E. African Nat. Hist. Soc., 22, 2334.Google Scholar
Richey, J. E., 1948. British Regional Geology—Scotland, the Tertiary Volcanic districts. 2nd Edit. Geol. Surv. U.K.Google Scholar
von Eckermann, H., 1958. The alkaline and carbonatite dykes of the Alnö formation on the mainland north-west of Alnö Island Kungl. Svensk. Vetenskaps Handl. Fjärde Serien., 7, No. 2.Google Scholar
von Eckermann, H., 1960. Guide to excursion C 27. XXIst Int. Geol. Congr., Norden.Google Scholar
von Eckermann, H., 1961. The petrogenesis of the Alnö alkaline rocks. Bull. Geol. Inst. Univ. Uppsala, 40, 2536.Google Scholar
Williams, H., 1941. Calderas and their origin. Univ. Calif. Tech. Publ., Bull. Dept. geol. Sci., V. 25, 239346.Google Scholar