 | | Journal (article/letter/editorial) |
| Geochemistry of the Younger Volcanic Islands of Tonga, S.W. Pacific by A. EWART, W. B. BRYAN, and J. B...Islands comprise a double island chain, and lie at the northern end of an active island arc extending NNE from...exposed on one island. The active volcanoes, the subject of this paper, form the western island chain, and...andesite dominates the islands of Hunga Ha'apai and Late (and also Tofua and Kao, which are not described in...include intermediate plagioclase, pigeonite, hypersthene, magnetite, plus potash feldspar and quartz in |
 | | Journal (article/letter/editorial) |
| The Pleistocene-Recent Tonga-Kermadec Arc Lavas: Interpretation of New Isotopic and Rare Earth Data in...range from extremely HFS element depleted (northern Tonga) to near N-MORB-like HFS element abundances in L'Esperance...account for differences in chemistry between the Tonga and Kermadec arc segments. The mechanism of LILE...zone, involving induced convection. The back-arc island of Niua fo'ou is geochemically quite distinct from...Pleistocene-Recent volcanoes erupted along the linear Kermadec-Tonga arc (Fig. 1) constitute a clear example of intra-oceanic |
 | | Journal (article/letter/editorial) |
| diopside at the corners (Figure 2). Normative hypersthene falls on the quartz-olivine edge. Albite falls...Trend) Tholeiitic (TH) magmas contain normative hypersthene together with ol ivine or quartz, and therefore...the right, and the residual magma may pass the hypersthene-plagioclase-diopside plane. Then, olivine stops...natural clinopyroxene contains a small amount of hypersthene molecule. Crystallization of olivine, plagioclase...TH series, such as in M iyake-jima, Kilauea, and Tofua (Figure 5), the Si02 content increases slowly with |
 | | Journal (article/letter/editorial) |
| from ocean ridges, back-arc basins, some young island arcs, and some continental flood basalts illustrates...a a r t [1] w h o a s s u m e d t h a t oceanic island basalt f o r m e d the b u l k o f the o c e a...nepheline-normative and the fresh one (DSDP39) is hypersthene-normative. The nepheline-normative basalts from...[126,130]. Basaltic andesites and a dacite from Tofua and Metis 100 60 40 • J ~ ~ • o c, ~ '~ \ BASALT...back-arc basin (Table 6). The Tonga Island samples are from an island arc (Table 6). The samples have |
 | | Book |
| character are found in: (4) subvolcanic regions of island arcs; and (5) ophiolites. The spatial relations...t e s u i t e i n : 4) Subvolcanic regions of island a r c s , e i t h e r as parts o f arc-tholeiitic...i o c l a s e , q u a r t z , a u g i t e , hypersthene, sanidine. hornblende, The low-K cummingtonite...lavas and pyroclastics is predominantly in the island arcs and orogeni e (mobile) continental marginal...Islands, New Hebrides, Fiji, Tonga-Kermadec Islands and New Zealand. 9. Tonga-Kermadec Islands (considered |
 | | Book |
| that potash contents of andesites increase across island arcs. By temperament VI Preface and age I prefer...active continental margin plate boundary ARC island arc plate boundary ATL Atlantic of passive continental...field strength (charge/radius) hy normative hypersthene Ihn ilmenite IRS incompatible elements +...parameters. Andesites are defined here simply as all hypersthene-normative volcanic rocks with Si02 from 53 to...While use of the noun andesite to denote all hypersthene-normative volcanic rocks with 53% to 63% Si0 |
 | | Book |
| is also poorly known. More sampling of the outer island arcs or ocean-side regions of the trenches is necessary... . . . . . . . . . . . . . . . . . . . . . . . Tonga Trench . . . . . . . . . . . . . . . . . . . . ...alteration. Hypersthene is usually less abundant (8-17%) than the clinopyroxene. The hypersthene is usually...usually altered into antigorite. Laminated hypersthene-bearing gabbros with parallel oriented cumulates of...of gabbro in which the orthopyroxene, usually hypersthene, is a constituent dominant over the clinopyroxene |
 | | Book |
| Island Arcs Deep Sea Trenches and Back-Arc Basins Maurice Ewing Series 1 Manik Talwani and Walter C...Winslow J. L. Worzel Maurice Ewing Series 1 Island Ares Deep Sea Trenches and Back-Are Basins Edited...American Geophysical Union Washington, D. C. Island Arcs Deep Sea Trenches and Back-Arc Basins Standard...participants were researchers active in the study of Island Arcs, Deep Sea Trenches and Back-Arc Basins. We...Sillitoe 303 Petrogenesis in Island Arc Systems, A. E. Ringwood 311 Island Arc Models and the Composition |
 | | Report (volume) |
| be built on Vulcan Island, west side of Rabaul Caldera, Papua New Guinea. The island was known to rise...Departments, including myself, inspected Vulcan Island with the object of seeing whether it might not...these reasons I stated that I did riot consider the island suitable for a Quarantine Station on account of...be ornamental, but would not be required if the island went up instead of down'." George H. Murray (1939)...156 Reunion Island Piton de la Fournaise 157 Contents VII Region 4: New Zealand, Tonga, and Kermadec |
 | | Book (edition) |
| the earth's development. continents and oceans, island chains and mountains, is an outcome of the most...the 100-fathom line. also ; Long Island Sound, '., Long Island and the Atlantic Border .with lines...Bathymetrle ; Cotidal - : ftr s. Unesin Long Island SoiiBil.tl—^^. the under-water Channel;; of Hudson...southwestward for 750 miles, and northeastward to the island of Jan Mayen. The feet; plateau has to the north...Ladrones and the Priendly Islands are craters The island chains of the ocean larity prevails elsewhere |
 | | Book (edition) |
| Editor-in-Chief Haraldur Sigurdsson University of Rhode Island, U.S.A. Associate Editors Bruce F. Houghton Institute...James D. L. White Claude Jaupart Seamounts and Island Building 383 Ralf Schmidt and Hans-Ulrich Schmincke...Yoshimoto Volcaniclastic Sedimentation around Island Arcs Manfred P. Hochstein and Patrick R. L. Browne...Scoria Cones and Tuff Rings 683 Seamounts and Island Building 383 Seismic Monitoring 1095 Sizes...Tsunamis 1005 Volcaniclastic Sedimentation Around Island Arcs Volcanism and Biotic Extinctions 627 1083 |
