 | | Journal (article/letter/editorial) | | silica and alkalis. Iron-rich nepheline from 01 Doinyo Lengai , as 4.6 percent iron. In nepheline with patchy...nephelinesin a nepheline tephrite from Ol Dionyo Lengai in Tanzania; shand (1922) mentioned zoned nepheline...northern slope of OI Doinyo Lengai about two miles south of Lake Natron, Tanzania. The nepheline crystals...his material was also collectedfrom OI Doiny'o Lengai. The optical property which enabiesone to observethe...iron contents of the nepheline.For example,iron sanidine prepared by Wones and Appleman (1961) has a B |  | | Journal (article/letter/editorial) | | com/locate/lithos Peralkaline silicate lavas at Oldoinyo Lengai, Tanzania Jurgis Klaudius ⁎, Jörg Keller Institut für...June 2006 Abstract A detailed study of Oldoinyo Lengai has led to the recognition of two major cone-building...phonolitic stage, Lengai I, forms the southern cone. The recent nephelinitic Lengai II developed following...a major sector collapse event over Lengai I. Petrography of Lengai II lavas show that nephelinite is combeite-...combeite- and wollastonite-bearing. All Oldoinyo Lengai lavas are peralkaline and highly evolved in terms |  | | Report (issue) | | Oldonyo Lengai (Oldoinyo Lengai) Volcano and Surroundings, Arusha Region, United Republic of Tanzania By David...Oldonyo Lengai (Oldoinyo Lengai) and surroundings, Arusha Region, United Republic of Tanzania: U.S. Geological... . . . . . . . . . . . . 17 Oldonyo Lengai . . . . . . . . . . . . . . . ..... . . . . . . . . . 32 Age of Oldonyo Lengai . . . . . . . . . . . . . . . .... . . 32 Previously Published Ages from Oldonyo Lengai . . . . . . . . . . . . . . . |  | | Journal (article/letter/editorial) | | forsterite–phlogopite ijolites at Oldoinyo Lengai Volcano, Tanzania: study of melt inclusions V.S. Sekisova...inclusions in minerals of ijolite xenoliths at Oldoinyo Lengai Volcano. Melt inclusions with different phase compositions...ijolite; nyerereite; natrocarbonatite; Oldoinyo Lengai Introduction The East African Rift System, expanding...the Gulf of Aden through Ethiopia, Kenya, and Tanzania, is divided into two large tectonic zones: Western...the present, for example, Oldoinyo Lengai, which is located in Tanzania, ~16 km south of Lake Natron, near |  | Jung, Seung Gi, Choi, Sung Hi, Ji, Kang Hyeun, Ryu, Jong-Sik, Lee, Der-Chuen (2019) Geochemistry of volcanic rocks from Oldoinyo Lengai, Tanzania: Implications for mantle source lithology. Lithos, 350. 105223 doi:10.1016/j.lithos.2019.105223 | Journal (article/letter/editorial) | | Geochemistry of volcanic rocks from Oldoinyo Lengai, Tanzania: Implications for mantle source lithology...Geochemistry of volcanic rocks from Oldoinyo Lengai, Tanzania: Implications for mantle source lithology...Geochemistry of volcanic rocks from Oldoinyo Lengai, Tanzania: 2 Implications for mantle source lithology...(S.H. Choi) 18 19 20 Abstract 21 22 Oldoinyo Lengai is the only active carbonatite volcano within the...the East African Rift Valley in 23 northern Tanzania. The volcano is dominated by peralkaline silicate |  | | Journal (article/letter/editorial) | | pyrrhotite followed by clinopyroxene-plagioclase-sanidine at relatively low pressure and temperature (P...Massif Central Sodalite-bearing phonolite Ol Doinyo Lengai Sadiman Nephelinite and Basanite Eifel Saghro...phenocrysts of sanidine); Middle Laacher See Tephra (MLST) with 15 vol% phenocrysts of sanidine, clinopyroxene...magma chamber) with 50–60 vol% phenocrysts of sanidine, plagioclase, and haüyne. Laacher See phonolites...contains up to 60 vol% phenocrysts of Cpx (3 vol%), sanidine (37 vol%), haüyne (5 vol%), plagioclase (12.5 |  | Fontijn, Karen, Elburg, Marlina A., Nikogosian, Igor K., van Bergen, Manfred J., Ernst, Gerald G.J. (2013) Petrology and geochemistry of Late Holocene felsic magmas from Rungwe volcano (Tanzania), with implications for trachytic Rungwe Pumice eruption dynamics. Lithos, 177. 34-53 doi:10.1016/j.lithos.2013.05.012 | Journal (article/letter/editorial) | | Late Holocene felsic magmas from Rungwe volcano (Tanzania), with implications for trachytic Rungwe Pumice...Available online 5 June 2013 Keywords: Rungwe Tanzania Alkaline magmas Trachyte Magmatic differentiation...eruptions a b s t r a c t Rungwe in southern Tanzania is an active volcanic centre in the East African...for melt inclusions and phenocrysts comprising sanidine, biotite, clinopyroxene, titanomagnetite, ilmenite...Democratic Republic of the Congo; carbonatitic Ol Doinyo Lengai, Tanzania; trachytic Longonot, Kenya) and calderas |  | | Report (volume) | | Chad, Ethiopia, Kenya, Malawi, Nigeria, Sudan, Tanzania and Uganda. However, in the last few years there...Depth to metamorphic basement in the Koobi Fora region from seismic and gravity data. 75 Watkins, R.T...record of Pleistocene deposits, Lake Natron basin, Tanzania... Bonnefille, G. & R„ Tiercelin, Sedimentation...countries—Chad, Eth¬ iopia, Kenya, Malawi, Nigeria, Sudan, Tanzania and Uganda. Geographical representation is very...waterfall dams and in rivers. There is thus no region of the world to match African lakes for the study |  | | Book | | OLpuvaAiI GoRGE AND LAETOLIL, GREGORY RIFT VALLEY TANZANIA; OLORGESAILIE, KENYA I51 10. MARY D, LEAKEY...WHITE. Fossil hominids from the Laetolil Beds, Tanzania 157 ROBERT M. SHACKLETON. Geological Map of...artifacts from the Kapthurin Formation, Baringo District, Kenya 337 361 C. Tue Laxe TurKANA (RupoLpH)... Cates ery — 7 ’ co) te | Ded uit Ai im, ol + ’ ai _ ie gta ve o* FT eee = = pre...It contains unique fossil localities in the Afar region of northern Ethiopia and the Omo valley in the |  | | Book | | differentiation 51 rocks Differentiation in wholly ol The diversity of magmatic liquid magmas Fractional...rocks 121 124 126 129 129 Contents Chapter 7 (ol Nad) General statement Textures and modal TS Geochemistry... Guttard studied the rocks of the Auvergne region of central France and recognized many recently...work (1894-1933) on the igneous rocks of the Oslo region of Norway; (b) the publication in 1895 of Alfred...uniquely able to provide substantial data about the region where they originated. The term primary magma should |  | | Book | | plane ⊥b. Examples: many important minerals like sanidine and orthoclase (7 Sect. 11.6.2), clinopyroxenes...(high) β-quartz (. Fig. 11.42), C2/m for monoclinic sanidine and P1̄ for the triclinic plagioclases (. Fig...cm . Fig. 2.5 Phenocryst of alkali feldspar (sanidine) in trachyte of the Drachenfels, Siebengebirge...coccoliths. From plankton sample of the Kimberley region, Australia, kindly provided by CSIRO Tasmania (picture...which the transport medium can move from the source region to the locus of ore precipitation; 5 an energy |  | | Book | | Resorbed crystal of quartz (Qz) in an olivinebearing (Ol) groundmass. The anhedral crystal shape and reaction...Compositions of basalt glasses from the Narrowgate region of the FAMOUS valley, Mid-Atlantic Ridge Geochemical...alkali basalts projected onto the normative Qz-Nph-Ol triangle Schematic cross-section of a typical island...relatively high temperatures. a = stability region for sanidine, b = stability for orthoclase, c = stability...7/26/2013 8:35:06 AM 1.4 Igneous Textures Plag Ol anorthosite anorthosite 90 dunite 90 90 gabbro |  | | Book | | fossil bacterial cell was found in seafloor chert. ol Classification of fossils Once placed nto intoits...aero men 4 . A A have been found in 4 the Isua region of ieGreenland. Earth's oldest rocks s é These...radioactive Pee Mee CUA PRUE cd Ch ne ccm RR ol La Ug CER Peed TERTIARY Cry CRETACEOUS Archaeopteryx...layer, for example, is younger than ca RolaMi ee ol ole aR a Rela |e a If this sequence is cut by...em Leta Mae Re SCENE ella) eco) RN Le Meer) CUS ol es Gare aec le ues Mar hele tury URC) Pree Reece |  | | Book | | discoveries, dated to 1.8 Ma at Olduvai Gorge in Tanzania. During these years, he was working for the Institut...African Early Acheulean of Peninj (Lake Natron, Tanzania) . . . . . 129 Fernando Diez-Martín, Policarpo...the TK Acheulean Site (Bed II, Olduvai Gorge, Tanzania): New Excavations 50 Years After Mary Leakey ...Dar es Salaam, P.O. Box 35050, Dar es Salaam, Tanzania Rita Melis Dipartimento di Scienze chimiche e...Acheulian occupation at Amanzi Springs, Uitenhage District, Cape Province. Annals of the Cape Provincial |  | | Book (edition) | | hidden by a nebular disc of material (diagonal dark region) similar in mass and size to the one that formed...lower side by the 660 km seismic discontinuity. The region between this depth and another prominent discontinuity...capable of moving, albeit very slowly. In this region, heat can be transferred by moving hot low-density...triple junction may be present beneath the Afar region of Ethiopia, with the Red Sea and Gulf of Aden...calcite, also CaCO3 – after a locality in the Aragon region of Spain); after some major chemical constituent |  | | Report (volume) | | Carbonatite lava flow from an eruption of Oldoinyo Lengai, Tanzania. Photo courtesy of Tobias Fischer. Series...more than 10,000 prospectors to the semi-desert region, and inevitably led to the recognition of diamond...Coal Mine 45, Kopeisk, Urals R3 Is River, Isovsky District, Urals C C I, To MCo CoF Pla I M M N, Ta Pla...Luobusha ophiolite complex, Autonomous Tibetan Region; (2) within the Mengyin kimberlite field, Linyi...three carbides that are unknown from any other region: qusongite (WC; Fang et al. 2009; Shi et al. 2009) |  | | Book (volume) | | volume and quality of gemstones being mined in that region. As new localities are identified and new gemstones...localities or gemstones may lose their appeal or a region may become unproductive – so the market can be...mineral zoisite), which was discovered in 1967 in Tanzania and is now available through many retail outlets...of Afghanistan, the Sverdlovsk region of the Urals, and the Altai region of north-western China. Gems formed...sapphires (Mogok), Pakistan rubies (Hunza Mountains), Tanzania rubies (Morogoro), and Vietnam rubies (Luc Yen |  | | Book (edition) | | within the city limits, but also to the surrounding region. In this edition of the Thesaurus, names of cities...newly added are followed by the word “region”; e.g., Stripa region. Names of materials, when used as GeoRef... isochrons isotopes SA SA Abruzzi Autonomous region on the Adriatic Sea. CO N414000N425500 E0144800E0130000...Islands Adalia use Antalya Adamawa Administrative region in N. BT Cameroon adamellite As of 1981, includes...changed from Greece to Mediterranean region. BT Mediterranean region SA Greek Aegean Islands Between Greece |  | | Book | | solids from a gas depend on temperature. In that region of the nebula occupied by the terrestrial planets...also have pushed ionized gases out of the inner region of the nebula. Again, there is a possibility that...up by this mass loss could have swept the inner region of the nebula clear of uncondensed gases. Planet...near the poles differs from that in the equatorial region. The succession of strata in the layered deposits...broadly correspond to terrestrial rocks in the region of the core/mantle boundary at 2900km (1800mi) |  | | Book (edition) | | the city limits, but also to the sur¬ rounding region. Terms for materials in GeoRef, for example, "iron...Aberfeldy Term introduced in 1989. Town and mining region in Tayside, central Scotland; oil field in Lloydminster...in GeoRef (see Introduction, p. vi). Autonomous region on the Adriatic Sea. CO N414000N425500 E0144800E0130000...SA Aleutian Islands Adalia use Antalya Adamawa Region in W Africa, now part of N central Cameroon and...BA Proterozoic BT Precambrian Adrar Interior region in W Mauritania near Western Sahara border. BT |  | | Book | | ... ,~. fro ........ , ~= ,II ol<,,'!p>I_.......) .11 ~ ••, .. < mI'J< "'101 ~"K' """ ,'" ol<"~",""",'" _ ..."........ ~. _ ,"" """"'."'n ....,"" ..,.. .... 'Of""" '''''''.-1 ,,ol, ..... '''l! .. h .. """"", '" ,..-.:I><'"'~I) '...continental crust, it is useful to begin by defining the region under consideration and to provide some generalities...rocks may not be representative of their source region. These elements include the alkali and alkaline-earth |  | | Book | | position of 56Fe; and (iv) the abundance peaks in the region past iron at the neutron closed shell positions...mixing caused by the convection, the entire unstable region evolves essentially chemically homogeneously—replenishing...of burning region (central or shell burning) and depleting the fuel elsewhere in that region at the same...burning of this fuel then commences outside that region. Table 1 summarizes the burning stages and their...maximum temperatures that have been reached in each region in the preceding hydrostatic burning stages (Table |
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