Fore-arc basalts and subduction initiation in the Izu-Bonin-Mariana system
Mark K. Reagan,Osamu Ishizuka,Robert J. Stern,Katherine A. Kelley,Yasuhiko Ohara,Janne Blichert-Toft,Sherman H. Bloomer,Jennifer Cash,Patricia Fryer,Barry B. Hanan,Rosemary Hickey-Vargas,Teruaki Ishii,Jun-Ichi Kimura,David W. Peate,Michael C. Rowe,Melinda Woods +15 more
Reads0
Chats0
TLDR
A recent dive with the JAMSTEC Shinkai 6500 manned submersible in the Mariana fore arc southeast of Guam has discovered that MORB-like tholeiitic basalts crop out over large areas.Abstract:
Recent diving with the JAMSTEC Shinkai 6500 manned submersible in the Mariana fore arc southeast of Guam has discovered that MORB-like tholeiitic basalts crop out over large areas These ''fore-arc basalts'' (FAB) underlie boninites and overlie diabasic and gabbroic rocks Potential origins include eruption at a spreading center before subduction began or eruption during near-trench spreading after subduction began FAB trace element patterns are similar to those of MORB and most Izu-Bonin-Mariana (IBM) back-arc lavas However, Ti/V and Yb/V ratios are lower in FAB reflecting a stronger prior depletion of their mantle source compared to the source of basalts from mid-ocean ridges and back-arc basins Some FAB also have higher concentrations of fluid-soluble elements than do spreading center lavas Thus, the most likely origin of FAB is that they were the first lavas to erupt when the Pacific Plate began sinking beneath the Philippine Plate at about 51 Ma The magmas were generated by mantle decompression during near-trench spreading with little or no mass transfer from the subducting plate Boninites were generated later when the residual, highly depleted mantle melted at shallow levels after fluxing by a water-rich fluid derived from the sinking Pacific Plate This magmatic stratigraphy of FAB overlain by transitional lavas and boninites is similar to that found in many ophiolites, suggesting that ophiolitic assemblages might commonly originate from near-trench volcanism caused by subduction initiation Indeed, the widely dispersed Jurassic and Cretaceous Tethyan ophiolites could represent two such significant subduction initiation eventsread more
Citations
More filters
Journal ArticleDOI
Ophiolite genesis and global tectonics: Geochemical and tectonic fingerprinting of ancient oceanic lithosphere
Yildirim Dilek,Harald Furnes +1 more
TL;DR: A review of these ideas as well as a new classification of ophiolites, incorporating the diversity in their structural architecture and geochemical signatures that results from variations in petrological, geochemical, and tectonic processes during formation in different geodynamic settings is presented in this article.
Journal ArticleDOI
Evolution of a Permian intraoceanic arc-trench system in the Solonker suture zone, Central Asian Orogenic Belt, China and Mongolia
Ping Jian,Dunyi Liu,Alfred Kröner,Brian F. Windley,Yuruo Shi,Wei Zhang,Fuqin Zhang,Laicheng Miao,Liqao Zhang,Dondov Tomurhuu +9 more
TL;DR: In this article, the identification of a fossil arc-trench system from the ophiolite-decorated Solonker suture zone in the southernmost Central Asian Orogenic Belt (CAOB) enables us to constrain the timing of pre-subduction extension (ca. 299,290, and 280,280), subduction initiation (c. 281, 273, and 255,248), and slab break-off in the Permian.
Journal ArticleDOI
The timescales of subduction initiation and subsequent evolution of an oceanic island arc
Osamu Ishizuka,Osamu Ishizuka,Kenichiro Tani,Mark K. Reagan,Kyoko Kanayama,Susumu Umino,Yumiko Harigane,Yumiko Harigane,Izumi Sakamoto,Yuki Miyajima,Makoto Yuasa,Daniel J. Dunkley +11 more
TL;DR: The Bonin Ridge and trench slope preserves the geological record of subduction initiation and subsequent evolution of the Izu-Bonin-Mariana (IBM) arc.
Journal ArticleDOI
The Indus–Yarlung Zangbo ophiolites from Nanga Parbat to Namche Barwa syntaxes, southern Tibet: First synthesis of petrology, geochemistry, and geochronology with incidences on geodynamic reconstructions of Neo-Tethys
TL;DR: The Yarlung Zangbo Suture Zone (YZSZ) ophiolites have been studied for almost 30 years and is the youngest of the sutures recognized on Tibet Plateau as mentioned in this paper.
Journal ArticleDOI
The 'subduction initiation rule': a key for linking ophiolites, intra-oceanic forearcs, and subduction initiation
Scott A. Whattam,Robert J. Stern +1 more
TL;DR: The Subduction Initiation Rule (SIR) as mentioned in this paper predicts that most ophiolites form during subduction initiation (SI) and that the diagnostic magmatic chemostratigraphic progression for SIR ophiola is from less to more HFSE-depleted and LILE-enriched compositions.
References
More filters
Chemical and isotopic systematics of oceanic basalt : implications for mantle composition and processes
TL;DR: In this article, trace-element data for mid-ocean ridge basalts and ocean island basalts are used to formulate chemical systematics for oceanic basalts, interpreted in terms of partial-melting conditions, variations in residual mineralogy, involvement of subducted sediment, recycling of oceanic lithosphere and processes within the low velocity zone.
Journal ArticleDOI
Chemical and isotopic systematics of oceanic basalts. Implications for Mantle Composition and Processes
Book
Orogenic Andesites and Plate Tectonics
TL;DR: In this article, the authors define Orogenic Andesite and discuss its properties and properties, including the following: 1.1 Topography, gravity, heat flow, and conductivity.
Journal ArticleDOI
Ti-V plots and the petrogenesis of modern and ophiolitic lavas
TL;DR: In this article, the authors applied the Ti/V plot to published data on ophiolites from a variety of postulated settings and in general supported the conclusions of previous investigators.