 | | Report (chapter) | | / K i ;1:/\. - u3-'~."\ -r ~ \\ -/:/ ", KENYA u __-/~.'\- " :. / I 2 ~ i TANZANIA 9 ~ ...fractionate to olivine-free nephelinite and to phonolite (Table 1). These phonolites are often glassy,...4- • LODWAR ~t~ MOROTO z --2 0 NAPAK ~ KENYA C e n o z o i c l a v a s and pyroclastic deposits...+ NYAMBENI I&UISHU ~ Kavirondo ~ M T . ~ A KENYA Olivine-poor volcanic A Olivine-rich volcanic ...TANZANIA 134~ ~ HANANG ~ 1380 FIG. 3. Map of Kenya and adjacent areas showing the present distribution |  | | Journal (article/letter/editorial) | | Differentiation Trends in Tertiary to Recent Lavas of Kenya* By J. B. WRIGHT ABSTRACT The distribution of Tertiary...Tertiary to Recent lavas in part of south-west Kenya is outlined, and attention drawn to the predominance...feldspar versus silica, for analysed lavas from Kenya and Tanganyika, are used to illustrate the trends...nephelinitic lavas and carbonatite complexes in Kenya is discussed and the possibility mooted that the... INTRODUCTION THE Tertiary to Recent lavas of Kenya are a typical continental sodic alkaline suite, |  | | Journal (article/letter/editorial) | | whole rock isochrons for the Monchique and Mt. Kenya complexes, together with a series of 87Sr/86Sr ratios...claimed as a reasonable representation of the volcano. Rocks have been chosen from the remaining complexes...lineage is represented in the present study by Mts. Kenya and Kilimanjaro, the "carbonatitic" lineage by Mt...the dissected complexes of Kisingiri (Rangwa), Jombo Hill, Ruri and Homa Mtn. Mt. Meru, like Moroto in...Choice of Samples The samples from Monchique, Mt. Kenya and Jombo Hill include examples of all major rock-types |  | | Journal (article/letter/editorial) | | extrusive carbonatites at Rangwa Caldera Complex, Kenya G. ROSATELLI1,*,{, F. WALL2 AND M. J. LE BAS3...of the large Kisingiri nephelinite-carbonatite volcano, Homa Bay District, western Kenya (0º34’S; 34º09’E)...relationship with the nephelinites of the Kisingiri volcano. Two hypotheses are discussed. A rising silicate...EY WORDS : carbonatite, Rangwa Caldera Complex, Kenya, nephelinite. Introduction TO date, extrusive rocks...Only the Oldoinyo Lengai G. ROSATELLI ETAL. volcano (Tanzania) erupts carbonatite lavas today (Dawson |  | | 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...centre at Rangwa became the focus of a central volcano, much of which is still preserved and when traced...(2) The Kisingiri Volcano (a) The Updoming of the "Sub-Miocene" Peneplain surface under Kisingiri (b) The...The Kisingiri Volcanic Series (i) The Lower Kisingiri Nephelinite Lavas (ii) The Middle Kisingiri Pyroclastic |  | | Journal (article/letter/editorial) | | precursor of rift development. The Flood ur Phonolite Phase (ca. 16 – 12 Ma) was most pronounced in...12 – 9 Ma) is poorly represented in the Southern Kenya Rift, though magmatic activity is recorded in the...– 4 Ma) is particularly well-represented in the Kenya Rift. Large-scale magmatic events include: commencement...Divergence (NTD) and Mt. Kenya, Rungwe Volcanic Province, and the Southern Kenya Rift. The Stratoid Phase...magmatic events at ca. 3 to 2.5 Ma within the Southern Kenya Rift and NTD. This phase manifests as basalts and |  | | Report (chapter) | | which migrated back and forth across Ethiopia, Kenya and Tanzania, with a western limit at about 38°E...limestones, shales and sandstones, in Ethiopia and Kenya, suggests low to moderate relief in the source areas...greatest elevation (to about 500 m) was in central Kenya and in Ethiopia (Saggerson & Baker 1965). Meanwhile...monoclinal warping and local faulting along the Kenya-Uganda border (Baker & Wohlenberg 1971). At Losodok...were erupted in southwest Ethiopia and northwest Kenya. By 25 m.y. ago, much of Ethiopia had been flooded |  | | Journal (article/letter/editorial) | | Geology, Lakehead University, 955 Oliver Road, Thunder Bay, Ontario P7B 5E1, Canada ABSTRACT Carbonatites are...nepheline syenite) and extrusive rocks (nephelinite, phonolite suite) of the nephelinite clan, e.g., at Fen (Norway)...(Sweden), Tororo and Napak (Uganda), and Shombole (Kenya). Notably absent are large volumes of melilite-bearing...carbonatite as tuffs and lavas at the Shombole (Kenya) and Hanang–Balangida (Tanzania) nephelinitic volcanoes...represent the roots of now eroded nephelinite–phonolite volcanoes. Melilitite-clan carbonatites This association |  | | Book (edition) | | field work on the Iron Hill complex of Gunnison County, Colorado, in 1912-1913. Although his final results...1955), L. J. Fick and C. van der Heyde (1959). Kenya: B. H. Baker (1953), G. L. Coetzee and C...rocks: Ravalli County, Montana, and Verity, British Columbia. Similar are those of Salmon Bay, Alaska, and..."Fourche a N . 8 Bauxite gc Cove Murfreesboro Volcano ¢ Se A a a os A ARKANSAS | = basalt—...feature that descends southwestward from Hudson Bay, defined on magnetic and gravimetric data. In Africa |  | Riley, T. R., Bailey, D. K., Harmer, R. E., Liebsch, H., Lloyd, F. E., Palmer, M. R. (1999) Isotopic and geochemical investigation of a carbonatite-syenite-phonolite
diatreme, West Eifel (Germany) Mineralogical Magazine, 63 (5) 615-631 doi:10.1180/002646199548736 | Journal (article/letter/editorial) | | geochemical investigation of a carbonatite-syenite-phonolite diatreme, West Eifel (Germany) T. R . RILEY1....an association of carbonatite, nephelinite and phonolite. The volcanic complex is dominated by three eruptive...xenoliths of calcite-bearing feldspathoidal syenite, phonolite and sanidine and clinopyroxene megacrysts, which...provinces worldwide. KEYWORDS" carbonatite, syenite, phonolite, stable isotopes, radiogenic isotopes. Introduction...was emplaced adjacent to an alkali-mafic maar volcano and a nephelinitic stratacone. The diatreme erupted |  | | 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...on the peralkaline silicic central volcanoes of Kenya and also favours an origin by crystal fractionation...pyroclastic deposits around central volcanoes in Kenya often show striking variations in the abundance...liquid phase from a CO2-saturated nephelinite or phonolite magma. There is, however, some disagreement over |  | | Journal (article/letter/editorial) | | and key genera of the African Land Mammal Ages. ’Kenya’ is the default country. Two-letter codes (e.g....WR: Warwire; Nyamavi ET: Lonyumun; Moiti; Allia Bay WT: Kanapoi; Ekora OM: Mursi Aterir; Karmosit AW:...Turkana (east side L. Turkana) KV: Kavirondo Rift (SW Kenya) OM: Omo River basin (NE extension Turkana) WR:...(Table 1), and is named for the district in northern Kenya where the Turkwel River cuts across the Rift Valley...Koru in the upper Kavirondo rift valley of western Kenya (Fig. 5), where the calcified tuffs that were mined |  | | Book | | fossil vertebrates in tuffs of the spectacular volcano that I had mapped in 19909. Thereafter, from 1959...sedimentological and palaeontological studies in the Kenya Rift Valley project. This, indeed, worked exceedingly... GREGORY RIFT VALLEY TANZANIA; OLORGESAILIE, KENYA I51 10. MARY D, LEAKEY. Olduvai Gorge 1911-1975:...SHACKLETON. Geological Map of the Olorgesailie Area, Kenya 171 12. 13. GLYNN LL. IsAAc. The Olorgesailie...Contents B. Tue Lake Barinco Basin, KENYA 14. GREGORY R. CHAPMAN Basin, Kenya & MAUREEN BROOK. Ghronostratigraphy |  | | Book | | northern portion in northern Tanzania, western Kenya, and eastern Uganda where the Nyanzian System, composed...through Rhodesia, Mozambique, Malawi, Tanzania and Kenya, and is characterised by ages of 400-700 m.y. (Cahen...rejuvenated antique sequences: the Nyanzian of Kenya (Sanders, 1965); the Bulawayan of Rhodesia (Johnson...and the Mozambique Belt in western Kenya. Bull. geol. Surv. Kenya, 7. ScureIner, G. D. L., and VAN NIgkERK...northeast-trending joints and shear zones. Senga Bay, Salima Granites with syenitic phases crop out sporadically |  | | Book | | derived from vol- cani vicus, or the seat of a volcano. Desmarest (1771) also worked in the Auvergne and...chamber that lies 3 km beneath the caldera of Krafla volcano (Einarsson 1978: 187). been cycle, This studied...approximately 40 to 10 km beneath the summit of Kilauea Volcano, between 10 and Hawaii, 3 km and that at depths... or into dykes that feed the rift zone of the volcano. According to Moore (1983: 139) there are several...chambers beneath the lower east rift zone of this volcano, and they are repeatedly filled with magma that |  | | Report (issue) | | Phosphorite General Age Mineralization Batemans Bay Marine chemical sediment nodular Ordovician New...Cretaceous 76 Australia Northern Territory Fannie Bay Marine chemical sediment nodular 78 Australia...pelecypods Late Miocene 121 Australia Victoria Waratah Bay Marine chemical sediment nodular 122 Australia...207 Canada Burritt Island 208 Canada Callender Bay 209 Canada Clay-Howells 210 Canada Crevier Secondary...Nonmarine sedimentary 223 Canada Ontario Argor (James Bay) Magmatic, carbonatite/alkalic 224 Canada Ontario |  | | Book (volume) | | pegmatite areas include the Pala area of San Diego County in California, the Nuristan area of Afghanistan...marble formed by the metamorphism of limestone. Kenya rubies (Mangari area of the Tsavo West National...provide evidence for the 1628 bc eruption of the volcano on Santorini (Thera) which is thought by some archaeologists...climate GEOARCHAEOLOGY 17 Figure 2 Sedgefield, County Durham. Fluxgate gradiometer data. 1 0.5 m. Romano...of these surveys, especially the 1802 survey of County Kilkenny by William Tighe (1766–1816), contain |  | | Book (volume) | | Radenhein (Austria), Liaotung (China), and Clark County, Nevada (USA). Evaporites The evaporite chemical...carbonate sediment. Trenton Series, Ordovician, Centre County, Pennsylvania, USA. (C) Silicified bioclastic sandstone...of greenish mud from a depth of 1920 m in Baffin Bay, offshore Canada, using a deep-sea grab, representing...replacements in peritidal sediments (e.g., Florida Bay, Andros Island). The dolomite-forming fluids are...nodules have been recorded in the Arabian Sea or the Bay of Bengal, most probably because of the high rates |
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