 | | Report (chapter) | | and sedimentation in the Kenya Rift from the equator northwards to Lake Turkana L.A.J. Williams & G.R.... Chapman SUMMARY: At the equator, the Kenya (Gregory) Rift Valley is a half-graben, faulted on the eastern...ofpyroclastics in earlylate Miocene 'plateau' phonolite sequences of the deep graben suggests that the...graben sector of the rift. The northern part of the Kenya Rift offers more rewarding areas for study of Tertiary...NNEtrending Kenya Rift Valley is about 100 km across--much wider than in southern Kenya. Lying E of the |  | | Journal (article/letter/editorial) | | magmatism in both rifts, and within the interposing Turkana re Depression. Notwithstanding the independent...independent evolution of the Main Ethiopian Rift and Kenya lP Rift prior to their quaternary linkage, magmatic...evolved compositions (flood na phonolites in Kenya, rhyolites in Ethiopia) dominated the landscape...impacted the entire region from the Afar margin to Kenya, though activity in the south Jo slightly predates...silicic volcanoes. Magmatic activity within the Turkana Depression broadly parallels that in both rifts |  | | Report (issue) | | activity and geology of the northern sector of the Kenya Rift Valley British Geological Survey Research...activity and geology of the northern sector of the Kenya Rift Valley P N Dunkley, M Smith, D J Allen and...activity and geology of the northern sector of the Kenya Rift Valley P N Dunkley, M Smith, D J Allen and...springs along its western shores. Geographic index Kenya Suf>jecr index Geothermal exploration, geology...activity and geology of the northern sector of the Kenya Rift Valley. British Geological Survey Research |  | | Report (chapter) | | Special Publications Outline of the petrology of the Kenya rift alkaline province B.H. Baker Geological Society...October 28, 2014 Outline of the petrology of the Kenya rift alkaline province B. H. Baker S U M M A R Y...eastern branch of the E African rift system in Kenya and northern Tanzania contains nearly the whole...majority of wellstudied suites of alkaline rocks in Kenya, including some unpublished data. Apart from questions...the province The alkaline volcanic province in Kenya and northern Tanzania is associated with the development |  | | Report (issue) | | and hydrogeology of the Kenya Rift Valley between Lake Baringo and Lake Turkana Research Report SD/92/1...and hydrogeology of the Kenya Rift Valley between Lake Baringo and Lake Turkana DJ Allen and W G Darling...and hydrogeology of the Kenya Rift Valley between Lake Baringo and Lake Turkana D J Allen and W G Dar ling...Keyworth DJ Allen W G Darling Geographical index Kenya Subject index Geothermal exploration, hydrogeology...nd hydrogeology of t he Kenya Rift Valley between Lake Baringo and Lake Turkana. British Geological Survey |  | | Journal (article/letter/editorial) | | rift system: Sr, Nd and Pb isotope evidence from Kenya Rift basalts Nick Rogers a; *, Ray Macdonald b ...basalts (MgO s 4 wt%) from the axial regions of the Kenya Rift. Samples have compositions ranging from hypersthenenormative...ratios in basalts from the axial regions of the Kenya Rift have 143 Nd/144 Nd = 0.51300 to 0.51255, 87...to s 20, broadly similar to values from OIB. The Kenya Rift cuts through basement of different ages and...inferred to be the Kenya mantle plume. Comparison with data from Afar suggest that the Kenya plume is distinct |  | | Report (chapter) | | Quaternary volcanoes Longonot and Suswa, south Kenya Rift STUART C. S C O T T 1 and IAN P. SKILLING...volcanoes Longonot and Suswa, located in the south Kenya Rift, each have a caldera formed by incremental...fissures and the caldera collapse centre at each volcano are parallel to rift faults, suggesting that rift...complexes in the central trough of the Gregory Rift, Kenya (Figs t & 2). Syn- and post-catdera pyroclastics...r61e of regional tectonics as a major control on volcano-structural events (Skilling 1993; C a m b r a y |  | | Report (chapter) | | extensional regime at each volcano. We found that extension in northern Kenya is orthogonal, whereas that...that in southern Kenya is oblique. Elliptical calderas in northern Kenya are orientated NWāSE, aligned...perpendicular to recent rift faults. In southern Kenya, the calderas are aligned NEāSW and lie oblique...labelled as: B, the Barrier; E, Emuruangogolak; Si, Silali; P, Paka; M, Menengai; L, Longonot; and Su, Suswa...Kenyan Dome is marked. (b) Summary geological map of Kenya after BEICIP (1987). Red arrows show the motion |  | Black, Stuart, Macdonald, Ray, Barreiro, Barbara A., Dunkley, Peter N., Smith, Martin (1998) Open system alkaline magmatism in northern Kenya: evidence from U-series disequilibria and radiogenic isotopes. Contributions to Mineralogy and Petrology, 131 (4) 364-378 doi:10.1007/s004100050398 | Journal (article/letter/editorial) | | Smith Open system alkaline magmatism in northern Kenya: evidence from U-series disequilibria and radiogenic...(<10 ka) and trachytes from the volcano Emuruangogolak in the Kenya Rift Valley. The basalts are mildly...conduits closely spaced around the summit of the volcano. Introduction The nature and eĀciency of diĀerentiation...studies of residence times in basalt-trachyte/phonolite centres. Widom et al. (1992) found, for rocks...characterized the evolution of the basanite-phonolite Laacher See volcano in Germany. DiĀerentiation of parental |  | | Report (chapter) | | peralkaline silicic rocks and caldera volcanoes of Kenya R. Macdonald Geological Society, London, Special...of Kenya R. Macdonald S U M M A R Y: The late-Quaternary trachytic caldera volcanoes of the Kenya rift...northern set of centres (the Barrier, Emuruangogolak, Silali and Paka) basalt is a major component and mugearites...plutonic processes while the volcano is at the magmatic stage. In Kenya the late-Quaternary caldera volcanoes...on the seven centres of the inner trough of the Kenya rift (Fig. 1) but, where relevant, information from |  | | Book | | magnetic surveys in northern Tanzania and southern Kenya B.W. Darracott, J.D. Fairhead and R.W. Girdler (Newcastle...of two areas in the Kenya Rift Valley J. Wohlenberg and N.V. Bhatt (Nairobi, Kenya) Planning of the airmagnetic...results of a seismic refraction experiment in the Kenya Rift D.H. Griffiths (Birmingham, Great Britain)...southwestern Afar is there a tendency for an axial volcano-tectonic lineament (Wonji fault belt) to extend...calderas most probably represents a tensional volcano-tectonic structure affecting the Danakil horst |  | | Journal (article/letter/editorial) | | interactions in volcanic rocks from the northern Kenya rift: geochemical evidence Kurkura Kabeto a,b,)...2 ) 54 wt.%. lavas from Samburu Hills, northern Kenya rift, exhibit significant variations in major and...Elsevier Science B.V. All rights reserved. Keywords: Kenya rift; Bimodal volcanism; SrāNd isotopes; AFC; Mantle;...carbonatiteānephlinitic, and basaltic rocks in Kenya and adjacent areas indicate derivation from heterogeneous...Hills area is located in the eastern edge of the Kenya rift, on the northern flank of the Fig. 1. Map |  | | Report (volume) | | continents. Field work was conducted in Chad, Ethiopia, Kenya, Malawi, Nigeria, Sudan, Tanzania and Uganda. However...Baker, B.FL Tectonics and volcanism of the southern Kenya Rift Valley and its influence on rift sedimentation...and sedimentation in the Kenya Rift from the equator northwards to Lake Turkana ... 59 Swain, C.J., Skinner...R.T. Volcano-tectonic control on sedimentation in the Koobi Fora sedimentary basin. Lake Turkana. 85 ...landtorm evolution in a rift valley basin, northern Kenya. Frostick, L.E. & Reid, I. Evolution and sedimentary |  | | 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 |  | | 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 |  | | | | Dronning Maud Land). Later-stage (170 Ma) felsic (phonolite comendite) dykes intrude the 176 Ma basanite tephrite... K EY WORDS : Gondwana, basanite, tephrite, phonolite, syenite, rift. Introduction THE Early to Middle...undersaturated foidites, and from Siundersaturated phonolite to comendite (Harris and FIG. 1. Location map...centres and displaying glassy chilled margins. Phonolite dykes account for ~10% of the total dykes observed...displaying ļ¬ow banding). Associated with the phonolite dykes is a suite of other felsic dykes. Typically |  | | Report (chapter) | | profiles from national parks and wildlife reserves in Kenya. Broad variations in soil trace element concentrations...studies in national parks and wildlife reserves in Kenya have shown *Present address: School of the Environment...soil profiles from wildlife conservation areas in Kenya was examined, and the implications for the trace...~.,Amboseli NP Fig. 1. Sampling locations in Kenya. wetness by hand (Faniran & Areola 1978). One soil... homogenized and passed through a 2mm sieve in Kenya. For the soil samples, c. 400 g of material was |  | | Journal (article/letter/editorial) | | NUMBER 9 PAGES 1225ā1253 1997 Petrogenesis of a PhonoliteāTrachyte Succession at Mount Sidley, Marie Byrd...of the Late Pliocene (5Ā·7 to 4Ā·2 Ma) Mt Sidley volcano, Marie Byrd Land, is examined using major and trace...a strongly silica-undersaturated basanite to phonolite series; (b) a more silica-saturated to -oversaturated...derive 35% mugearite, 25% benmoreite and 20% phonolite as residual liquids. Fractional crystallization...extreme Mt Sidley, an Early Pliocene composite volcano, is at the south end of the Executive Committee |  | | Journal (article/letter/editorial) | | SĆørensen, 2005; Neumann, 1976), and Warrumbungle volcano, NSW (Duggan, 1988). a: Variation in the diops...(peralkaline trachyte rather than nephelinite, phonolite or ultramaļ¬c lamprophyre) or too strongly reducing...pyroxene in felsic volcanics from the Warrumbungle Volcano, central New South Wales, Australia. Mineralogical...498ā516. Macdonald, R., 2003. Magmatism of the Kenya Rift Valley: a review. Transactions of the Royal...between trachyte and carbonate in ash ļ¬ow tufts from Kenya. Contributions to Mineralogy and Petrology 114, |  | Jung, S., Mezger, K., Hauff, F., Pack, A., Hoernes, S. (2013) Petrogenesis of rift-related tephrites, phonolites and trachytes (Central European Volcanic Province, Rhƶn, FRG): Constraints from Sr, Nd, Pb and O isotopes. Chemical Geology, 354. 203-215 doi:10.1016/j.chemgeo.2013.06.026 | Journal (article/letter/editorial) | | a strongly silica-undersaturated basanite to phonolite lineage or a less silica-undersaturated alkali...large distance (ca. 30 km) between some of the phonolite occurrences renders this suggestion unlikely....90 50 70 Frankfurt 90 50Ā°34' Hilders 90 Phonolite, Trachyte Alkali basalt Hornblende-Basalt Sample...Steinwand 50Ā°29ā² 55955 Phonolite 5425 Kleinsassen Hohlstein 50Ā°30ā² 56038 Phonolite 5425 Kleinsassen Kesselberg...the highly evolved rocks straddle the trachyteāphonolite boundary in the total alkaliāSiO2 diagram (Fig |  | | Report (issue) | | (Bottom) Carbonatite lava at Oldoinyo Lengai volcano, northern Tanzania. Courtesy Alexander J. Teague...upper-mantle low-velocity anomaly beneath Ethiopia, Kenya, and Tanzania: Constraints on the origin of the...and natrocarbonatite lavas at Oldoinyo Lengai volcano, Tanzania. . . . . . . . . . . . . . . . . . ....fingerprints of mantle metasomatism beneath Nyos volcano (Cameroon volcanic line) . . . . . . . . . . ....40Ar-39Ar ages and petrogenesis of the Massif dāAmbre volcano, northern Madagascar . . . . . . . . . . . . . |  | | Journal (article/letter/editorial) | | Suite from the Southern Part of the Gregory Rift, Kenya Brian H. Baker 1, G o r d o n G. Goles 1, William...faulting. 1. Introduction The Gregory rift in Kenya is a part of the eastern branch of the Afro-Arabian...genetic associations have been distinguished in the Kenya rift alkaline province: a strongly alkaline association...transitional basalts, trachytes, and occasional Kenya-type phonolites, pantellerites, and comendites....Rift located immediately north of Olorgesailie volcano has been remapped (Fig. 1) and the stratigraphy |  | Macdonald, R., Belkin, H. E., Fitton, J. G., Rogers, N. W., Nejbert, K., Tindle, A. G., Marshall, A. S. (2008) The Roles of Fractional Crystallization, Magma Mixing, Crystal Mush Remobilization and VolatileāMelt Interactions in the Genesis of a Young BasaltāPeralkaline Rhyolite Suite, the Greater Olkaria Volcanic Complex, Kenya Rift Valley. Journal of Petrology, 49 (8) 1515-1547 doi:10.1093/petrology/egn036 | Journal (article/letter/editorial) | | Rhyolite Suite, the Greater OlkariaVolcanic Complex, Kenya Rift Valley R. MACDONALD1,2*, H. E. BELKIN3, J....rhyolite dome and lava field in the south^central Kenya rift valley that has been marked over the past 20...(Olkaria), and the neighbouring centres on the Kenya Dome (Eburru, Longonot and Suswa). From Heumann...O F T H E G OVC The GOVC is part of the central Kenya peralkaline province (CKPP; Macdonald & Scaillet...with an area of crustal upwarping known as the Kenya Dome. Crustal thickness beneath the Dome is 30^35 |  | | Report (volume) | | concentrations in dry 39 season pastures in western Kenya Maska tt, J. & THornToN, I. The distribution of...utilization by elephants in the Mount Elgon Region, Kenya 63 Seiinus, O. FRANK, A. & GALGAN, V. Biogeochemistry...acid 213 223 25h and gas contamination at Poas volcano, Costa Rica 239 Ouiver, M. A. Kriging: a method...range of developing countries including India, Kenya, Tanzania, Uganda and Sri Lanka. Of the 34 papers...Zimbabwe (Fordyce et al.), Kenya (Jumba et al; Maskall & Thornton) and the Kenya-Uganda border area (Bowell |  | | Book (edition) | | historic eruptions 251 and natural gas 130 13.11 Volcano prediction 257 9.10 Exploration for oil and...ask: What are the lavas made of? How does the volcano work and how is the heat generated? Where do the...the lavas and gases come from? When did the volcano first begin to erupt and when is it likely to erupt...It is quite useless, for example, to ask why a volcano erupts, or why the sky is blue, or why there are...Sicily, Hephaestus was identified with the local volcano-god Vulcan or Volcanus. The eruptions of lava and |
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