 | | Journal (article/letter/editorial) | | whole rock isochrons for the Monchique and Mt. Kenya complexes, together with a series of 87Sr/86Sr ratios...participation in the origin of nephelinites, nepheline syenites, ijolites or peralkaline oversaturated...consist of alkali gabbros, intermediate rocks, nepheline syenites, lamprophyres and peralkaline or agpaitic...nephelinites, ijolites, melilitic rocks, pyroxenites, nepheline syenites and carbonatites. The absence of calcic...the division of petrogenetic opinion regarding nepheline syenites; moreover, nephelinites and ijolites |  | | Journal (article/letter/editorial) | | to those better known to British geologists in Kenya Colony, and in both areas have received a considerable...the north-west side of the Luhembero, an isolated hill of Karroo rocks rising out of the low plains to...miles. In Kenya Colony at Mt. Jombo, about 20 miles inland, Gregory 3 describes nepheline-syenite and...volcanic events which built up Kilimanjaro and Kenya. The present contribution records the occurrence...direction in the region—would pass close to the Jombo Hill in Kenya Colony, previously referred to, and about |  | | Book | | Geological Sciences Mineral Resources Division Nepheline —-Syenite and Phonolite HMSO 15s Od Digitized...Natural Environment Research Council Contents Nepheline-Syenite and Phonolite Introduction Chemistry...Mineralogy and Classification of Nepheline-Bearing Rocks Origin of Nepheline-Bearing Rocks Mining and Treatment...Economic Assessment of Nepheline-Syenite and Phonolite Occurrences Nepheline-Syenite and Phonolite in...in Commonwealth Countries United Kingdom Ghana Kenya Malawi Rhodesia Sierra Leone Tanzania Uganda Zambia |  | | Journal (issue) | | the Colonies With appende,d summary reports on: Kenya . Uganda • Tanganyika . • • • • • • Northern...Resources COLONIAL GEOLOGICAL ABSTRACTS Part I .-Kenya . • • • • •• Vll ••• Vlll CONTENTS PAGE...selection of these abstracts deals exclusively with Kenya. Papers published since 1950 have been abstracted...phyric anorthoclase. (d) Phonolitic trachytes with nepheline, socialite and analcite. The mineralogy and chemical...form of nepheline. Fresh felspathoids are confined to the phonolitic trachytes. Both nepheline and sodalite |  | | Report (issue) | | Report No. 45 COLONY AND PROTECTORATE OF KENYA MINISTRY OF COMMERCE Ä N D INDUSTRY GEOLOGICAL SURVEY...of South Nyanza, in the south-western corner of Kenya. It is a most important area as in its northern...Rusinga Island 49 Fig. 6—Geological section of Kiahera hill, Rusinga Island 52 Fig. 7—Sketch section of the...1,400 square miles of South Nyanza, in western Kenya, on the shore of Lake Victoria! The land area is...part of the south-west quarter of Degree Sheet 41 (Kenya), corresponding with the Directorate of Colonial |  | | Book (edition) | | those of the undersaturated alkalic group—the nepheline syenites and their relatives. Rare, mineralogically...Cu, barite, vermiculite, CaCOs;, fluorite, Ti, nepheline, and Zr. HISTORY OF CARBONATITE STUDIES Although...bodies of limestone intimately connected with the nepheline rocks. Generally the limestone is INTRODUCTION...the vicinity of the limestone occurrences the nepheline rocks are often also very rich in calcite, which...very common in the limestone, as well as in the nepheline-syenite bodies which occur at some localities |  | | Report (chapter) | | but the assemblages [quartz + plagioclase] and [nepheline + plagioclase] respectively distinguish them from...2.65~ respectively (Furnes & Stillman 1987). Nepheline and sodalite minerals occur only in AL and UML...2 58.74 21,31 0.86 -0.05 9.35 0.32 -? 0.027 Nepheline 2 Melilite3 Alkaline Ultramafic 21 46.5 _...Spain (Vitrac-Michard et al. 1977); 15 sannaite, Jombo, Kenya (Rock 1976); 16 monchiquites, Hopi, U.S.A. (Powell...(Powell et al. 1966); 18 alnoitic rock, Rangwa, Kenya (Rock 1976); 19 damtjernites, Fen, Norway (Griffin |  | | Report (volume) | | 273 BAKER, B. H. Outline of the petroIogy of the Kenya rift alkaline province 293 MACDONALD,R. Quaternary...peralkaline silicic rocks and caldera volcanoes of Kenya 313 WOOLLEY, A. R. & JONES, G. C. The petrochemistry...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...on the peralkaline silicic central volcanoes of Kenya and also favours an origin by crystal fractionation |  | | Report (issue) | | (English). Microprobe analyses (1) from Alkalic rocks, Kenya. AENIGMATITE. Ike, (J. African Earth Sci. 3, 101-105)...48, 1-12 (1984). Microprobe analyses (4) from nepheline syenites, S. Greenland. AESCHYNITE-(ND). Zhang...Microprobe analyses (23) from Franklin and Sterling Hill, N.J. Partial solid solution with chondrodite, ALLEGHANYITE...^Mn 3.i7M8-| ,68 Zn 6 19 Fe O 02^ from Sterling Hill, N.J., monoclinic, P2 1/b, a O27, b 10.6^3, c 8...(1981)(English). Electron probe analyses (2) from peridotite, Kenya. AMPHIBOLE. Ivanitskii, et al., (Problem Kristallokhim |
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