 | | Journal (article/letter/editorial) | | L C R Y S T A L L I Z A T I O N IN B O U V E T ISLAND LAVAS ANTON P. LE ROEX and A.J. E R L A N K Departments...crystallization in Bouvet Island lavas. J. Volcanol. Geotherm. Res., 13:309---338. Bouvet Island, situated near...more evolved compositions) to give rise to the Bouvet Island rhyolite. Extensive fractional crystallization...hawaiite to mugearite, suggesting that the Bouvet Island hawaiites correspond in composition to a six...crystallization on this surface. INTRODUCTION Bouvet Island (lat. 54°26'S, long. 3°25'E) is situated near |  | | Journal (article/letter/editorial) | | feldspar. I t is the only unquestionable eomendite obsidian containing quartz phenocrysts that has come to...2 -3.6 65.5 82.3 8.2 9.5 Spec. 1. Ascension Island, Atlantic. Scarce phenocrysts of alkali felspar...felspar ( < 1.0 %). (No. 15,375). Spec. 2. Bouvet Island, Atlantic. Scarce phenocrysts of anorthoclase ( <...< 1.0% ). (No. B2). Spec. 3. Bouvet Island. Phenocrysts of alkali felspar Or~0 (2.5%). (No. W T 18B)....Spec. 4. Easter Island (Motu Iti), Pacific. Aphyrie (No. 17,525). Spec. 5. Easter Island (Rana Kau), Pacific |  | | Journal (issue) | | Introduction Australian Antarctic Territory Bertha Island, Sheehan Nunatak i Scullin Monolith Chemistry and...Clarence Island South Orkney Islands Inaccessible Islands (a) Coronation Island (b) Signy Island (c) Powell...Michelsen Islands (d) Fredriksen Island (e) (/) Laurie Island Graptolite Island. (g) . Basaltic and other...rocks from Bouvet Island and various DREDGE STATIONS Discovery Tablemount area ii Bouvet Island iii Off...metamorphism. Greenschist facies rocks from Clarence Island, in the Scotia Arc, together with igneous and other |  | | Journal (article/letter/editorial) | | Petrogenesis of the volcanic suite of Bouvetøya (Bouvet Island), South Atlantic TORE PRESTVIK, STEVEN GOLDBERG...Petrogenesis of the volcanic suite of Bouvetøya (Bouvet Island), South Atlantic. Norsk Geologisk Tidsskrift...to the volcanic istand of Bovetøya (close to the Bouvet Triple Junction) are discussed and compared with...with previously published data from the island. The rock types, hawaiite, benmoreite, and peralkaline trachyte...rocks are !hose of a moderately enriched oceanic island suite. On several isotope plots Bouvetøya rocks |  | | Journal (article/letter/editorial) | | Sigmond, E. M. 1977: The deoiogy and petrology of Bouvet~ya, south Atl;mtic Ocean. Lithos 10, 213-234, Oslo...Oslo. ISSN 0024-4937. The Quaternary island Bouvetoya is situated near the triple junction on the South...address: Geologisk Institutt, N-7034 Trondheira.NTH, Norway. Bouve,tOya is situated at the southern end of...and triple junctions, e.g. Ascension and Easter Island (Baker 1973), and their genesis has been attributed...of the present knowledge of the geology of the island together with further petrological study, which |  | | Journal (article/letter/editorial) | | increases in rocks with <1 wt.% MgO. Data sources: Bouvet Island Le Roex and Erlank (1982); Fantale Gibson (1972);...(SB30) in this study is a peralkaline rhyolitic obsidian from the Olenguruoni centre. Black et al. (1997)...rock, consistent with data for glasses from Mayor Island peralkaline rhyolites and for whole-rock analyses...with abundances of 31 ppm and 73 ppm in two Mayor Island rhyolites with PI of 1.44 and 1.74, respectively...(Table 1). The two peralkaline rhyolites from Mayor Island had coefficients of 0.91 and 2.0, respectively (Ewart |  | | Journal (article/letter/editorial) | | Springer-Verlag 1974 Petrology and Geochemistry of Easter Island P. E. B a k e r * a n d F. B u c k l e y Department...Durham Received November 13, 1973 Abstract. Easter Island has developed around three volcanoes Poike, an...are concentrated in the southwestern part of the island on or around Rano Kau. The basaltic rocks, which...level. P r e v i o u s geological work on t h e island includes accounts b y Chubb (1933), L a c r o i...well k n o w n occurrence of r h y o l i t i c obsidian was f i r m l y dismissed b y B a n d y (1937 |  | | Report (issue) | | of modal phenocrysts in samples of porphyritic obsidian.-.______ 4. Graph showing relations between volume...phenocrysts and agpaitic index in samples of porphyritic obsidian having >8 percent of phenocrysts-___--_-_____...University of Reading, United Kingdom. By choosing only obsidian, we may be imposing a selective bias in favor...crystallize. We suggest that this compilation of obsidian analyses is the logical first step towards quantifying...closely connected with comenditic rocks. On Easter Island, for Nl INTRODUCTION PETROGENETIC IMPORTANCE OF |  | | Report (chapter) | | 75 wt. %) water-poor (H20+=0.10%) pantelleritic obsidian from Eburru (Bailey et al. 1974) show that alkali...obsidians Postand 0 and caldera rr trachytes obsidian I I I I I I i 200 400 600 800 1000...Fig. 2. The generalized trend for the oceanic Bouvet Island basalt-comendite sequence is also shown (Imsland...Lake Rudolf region, II, The lavas of North Island, South Island and the Barrier. Lithos, 4, 305-23. CLAGUE...SIGMOND, E. M. 1977. The geology and petrology of Bouvet~ya, south Atlantic Ocean. Lithos, 10, 213-34. JOHNSON |  | | Journal (article/letter/editorial) | | and Associated Plutonic Inclusions of Ascension Island by CHRIS HARRIS1 Dept. of Geology and Mineralogy...revisedform 5 May 1983) INTRODUCTION Ascension Island is a large composite volcano situated at approximately...14°W in the South Atlantic Ocean (Fig. 1). The Island is 98 km2 in area and represents the uppermost...ABSTRACT The lavas and pyroclastics of Ascension Island contain a suite of plutonic inclusions which range...HM side of the FMQ reaction curve. ASCENSION ISLAND LAVAS 425 Fernando Po » Principe Sao Tome • Annobon• |  | | Journal (article/letter/editorial) | | Graduate School of Oceanography, University of Rhode Island, Narragansett, RI, USA (robp@gso.uri.edu, dhondt@gso...break-up of Gondwana (Karoo LIP) to present day (Bouvet TJ) Nano-scale phenomena in the interaction between...Ni-rich glass [3] recovered from the MAR near the Bouvet Triple Junction. This glass (206Pb/ 204Pb = 17...on tectonic reconstructions, the Karoo LIP and Bouvet TJ were closely spaced at the time of opening of...Water Research, Gaustadalleen 21, NO-0349, Oslo, Norway Anoxic conditions in the water column are abundant |  | | Report (issue) | | Pomona Ridgecrest Ridgecrest Superstition San Miguel Island Superstition Mountain Sawmill Short Canyon Warm...the usual swarms. There was one in late May near Obsidian Butte at the southern end of the Sal ton Sea....offshore 29 km (18 mi) northeast of San Clemente Island. North Elsinore - Region 6 No significant seismic...REG OFF CST COSTA RICA NR COAST NICARAGUA TALAUD ISLAND TAIWAN REGION TONGA ISLANDS NEW BRITAIN, P.N.G...5.8 95.4 E 620 5.1 152.5 E 10 5.4 129.7 W BOUVET ISLAND REGION E COAST KAMCHATKA BONIN ISLANDS REG. |  | | Report (issue) | | Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, Connecticut, New York, New Jersey, Pennsylvania...Corsica. Spain. Portugal. Azores. Spitzbergen. Norway. Sweden. Finland, Kola. Germany: Westphalia, Rhineland...many books on the geology of various suggests the Island of Rhodes rather than the State of regions, books...books of travel, and other volumes were Rhode Island. Warren's name root is adopted in V.. searched for...Proceedings ........................................ NORWAY. Geologisk Undersogelse, Publica.tions ...... |  | | Book (volume) | | Atlantic Baker I. Introduction... .. . II. The Island Groups . . . ba A. Group 1. Mildly Alkaline to...by the actively volcanic Tristan da Cunha—Gough Island Group and its trace during sea-floor spreading...geophysical results and augmented by dredge hauls, island exploration, etc., have been predicated on the...stratigraphic test was drilled on the volcanic island of Santa Barbara. been drilled in the offshore...2-CST-1-BA. The well 2-SB-1-BA drilled on Santa Barbara Island on the Abrolhos bank penetrated lava layers related |  | | Report (volume) | | Geochemistry of ocean island basalts from the South Atlantic: Ascension, Bouvet, St. Helena, Gough and...lavas and associated granite xenoliths of Ascension Island 269 FITTON, J. G. The Cameroon line, West Africa:...very rare and not so clearly defined as in ocean island chains, probably because the continental lithosphere...deep mantle plumes as suggested for the Hawaiian island chain (Clague). The entire convecting upper mantle...produces MORB (Fitton). Geochemical studies on ocean island basalts from the South Atlantic Introduction |  | | Book | | 277, 279 281 283 283 284 284 Chapter 14: Gough Island . . . 286 286 286 287 287 289 302 304 305 Geology...the nearest mainlands. Of the fourteen islands-island groups mentioned, not all are what are generally...Iherzolitic and dunitic peridotites of Timor, Réunion Island and Piedmont, Italy. He therefore affirmed that...taken from WasxincTon of similar deposits from Norway (No. 3) and France (No.4). Specimen No.2 gave...specimen) 2. St. Paul Rocks. (WasHINGTON specimen) Norway. ee a ; ee oe rom Mauillac, Quercy, The Institute |  | | Journal (article/letter/editorial) | | LEi 7 RH, UK The volcanoes of the South Sandwich island arc follow three distinct series: low-K tholeiitic...two-phase flow may be needed to explain fully the inter-island variations. of the Scotia Sea in the South Atlantic...of the most gecchemically coherent of the active island-arc systems (Baker, 1982) and are frequently cited...Fractional Crystallization Beneath the South Sandwich Island Arc JOURNAL OF PETROLOGY VOLUME 36 •ftCandlemas...Antarctic Survey subsequently sampled Zavodovski Island further (J. S. Smellie, personal communication) |  | | Book | | like this one from Kilauea volcano in Hawaii’s Big Island, can be watched and photographed safely. (Photograph...starting point for our journey is the scenic North Island of New Zealand, one of the world’s prime volcanic...historical records exist. If people lived in the island at Volcanic tours 5 Fig. 1.2. The distribution...eruption. Aside from the record-setting Taupo, North Island has other volcanic areas that have been active...event compared with what could happen again in the island. The Waiotapu thermal area is a wellknown tourist |  | | Book | | past tectonic environments (e.g. mid-ocean ridge, island arc) from the compositions of ancient igneous rocks;...subduction-related volcanic rocks is shown in Fig. 1.6. In many island arcs, the potassium content of volcanic rocks increases...0 tion 55 ssocia line a -alka calc Low-K (island 50 line o ass sociation arc tholeiite) as 60...tectonic environments on Earth (e.g. mid-ocean ridges, island arcs, back-arc basins, intraplate oceanic islands...basalt’ (often abbreviated to ‘MORB’) and ‘ocean-island basalt’ (OIB) being obvious examples. As we shall |  | | Book | | Bibliography: p. Includes index. 1. Islands. 2. Island ecology. GB471.M46 1986 551.4'2 ISBN 0-7167-5017-1... 10 x I 27 51 71 87 109 129 147 171 Island Life from a Geological Viewpoint Sources of the...Cunha • Gough . Falkland Is. South Georgia • Bouvet •. SOUTH ■ SANDWICH IS. 90° 60° 30° 0° dp...at Tahiti. Helena, a small, isolated, volcanic island in the South Atlantic, and all his food came from...his few friends. 2 Chapter l Maiao Island in the Society Island group—an isolated peak in a vast sea |  | | Book | | three categories: those of (1) ocean basins; (2) island arcs and continental margins; and (3) continents...underlie much of the inaccessible ocean floor. The island arcs and orogenic con¬ tinental margins are the...Hawaii Galapagos Reunion Comoro Islands Marion Island 2 5 4 1 1 Continental intraplate volcanism East...Geological map of the northern part of Macquarie Island (after Griffin and Varne 1980). 5 Igneous activity...crust may be seen above sea-level is Macquarie Island, situated 1100 kilometres south-west of New Zea¬ |  | | Report (issue) | | that observed for the ridge propagator near Easter Island (compare Fig. 3 of this study with Fig. 6 of Naar...propagation along the East Pacific Rise near Easter Island: Journal of Geophysical Research, v. 91, p. 3425-3438...rates of plates, rollback rate of trench axis and island are tectonics: Tectonophysics, v. 146, p. 353-364...(Plio-Pleistocene) Glassy rhyolitic flows with large (1 m) obsidian fragments MVB Green lithic-free ash-flow Jala-Juanacata...Jala-Juanacata group Rhyolite and obsidian breccia with intercalation of ash fall White-yellowish ash |  | | Book (edition) | | computer. The 1961 Mohole drilling off Guadalupe Island, Mexico, where the Pacific is more than two miles...about 575 feet below the ocean floor near Guadalupe Island, off "space probes" launched by the United States...silica or alumina, iron or calcium. Such names as obsidian, pitchstone, or scoria therefore indicate texture...of larger size. The wave-cut cliffs of Staffa Island, Scotland, display basaltic lava with columnar...of the pebbles in conglomerate on Bonaventure Island, Quebec, were rounded this by waves before they |  | | Book (edition) | | up during the 1961 Mohole drilling off Guadalupe Island, Mexico, where the Pacific is more than two miles...about 575 feet below the ocean floor near Guadalupe Island, off the coast of Mexico. The Pacific Ocean here...sand grains to particles of larger size. Staffa Island, Scotland, display basaltic lava with columnar...the pebbles in this conglomerate on Bonaventure Island, Quebec, were rounded by waves before they washed...in the Swiss and Bavarian Alps, the highlands of Norway, the Rockies and the Andes. Many of the angular |  | | Book | | Giant’s Causeway in Antrim, and Fingal’s Cave on the island of Staffa in the Hebrides. More than 90% of vol-...of fracture of certain rocks and minerals (e.g. obsidian, quartz) takes the form of a curved, concentrically...small scale, in a glassy igneous rock such as obsidian (% Rhyolite) or > pitchstone. Many of the initial...in the form of » spherulites, e.g. spherulitic obsidian. Devitrification may ultimately spread throughout...the Middle East, and the Mediterranean. (Cf. > Island arc distribution.) Submarine earthquakes occur |
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