東華大學圖書館 |

Language: English

Help

回圖書館首頁

手機版館藏查詢

Back

Switch To: Labeled | MARC Mode | ISBD

A geochemical study of crustal pluto...

Johnson, Julie Ann.

Linked to FindBook

Google Book

Amazon

博客來

A geochemical study of crustal plutonic rocks from the southern Mariana Trench forearc: Relationship to volcanic rocks erupted during subduction initiation.

Record Type:	Electronic resources : Monograph/item
Title/Author:	A geochemical study of crustal plutonic rocks from the southern Mariana Trench forearc: Relationship to volcanic rocks erupted during subduction initiation./
Author:	Johnson, Julie Ann.
Description:	223 p.
Notes:	Source: Dissertation Abstracts International, Volume: 75-12(E), Section: B.
Contained By:	Dissertation Abstracts International75-12B(E).
Subject:	Geochemistry. -
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3632526
ISBN:	9781321119442

A geochemical study of crustal plutonic rocks from the southern Mariana Trench forearc: Relationship to volcanic rocks erupted during subduction initiation.
Johnson, Julie Ann.

A geochemical study of crustal plutonic rocks from the southern Mariana Trench forearc: Relationship to volcanic rocks erupted during subduction initiation. - 223 p.

Source: Dissertation Abstracts International, Volume: 75-12(E), Section: B.

Thesis (Ph.D.)--Florida International University, 2014.

This item is not available from ProQuest Dissertations & Theses.

Two suites of intermediate-felsic plutonic rocks were recovered by dredges RD63 and RD64 (R/V KK81-06-26) from the northern wall of the Mariana trench near Guam, which is located in the southern part of the Izu-Bonin-Mariana (IBM) island arc system. The locations of the dredges are significant as the area contains volcanic rocks (forearc basalts and boninites) that have been pivotal in explaining processes that occur when one lithospheric plate initially begins to subduct beneath another. The plutonic rocks have been classified based on petrologic and geochemical analyses, which provides insight to their origin and evolution in context of the surrounding Mariana trench.

ISBN: 9781321119442Subjects--Topical Terms:

539092
Geochemistry.

A geochemical study of crustal plutonic rocks from the southern Mariana Trench forearc: Relationship to volcanic rocks erupted during subduction initiation.
LDR:03423nmm a2200337 4500 001 1988014
005 20150716112157.5
008 150803s2014 ||||||||||||||||| ||eng d
020 $a 9781321119442
035 $a (MiAaPQ)AAI3632526
035 $a AAI3632526
040 $a MiAaPQ $c MiAaPQ
100 1 $a Johnson, Julie Ann. $3 2122859
245 1 2 $a A geochemical study of crustal plutonic rocks from the southern Mariana Trench forearc: Relationship to volcanic rocks erupted during subduction initiation.
300 $a 223 p.
500 $a Source: Dissertation Abstracts International, Volume: 75-12(E), Section: B.
500 $a Adviser: Rosemary Hickey-Vargas.
502 $a Thesis (Ph.D.)--Florida International University, 2014.
506 $a This item is not available from ProQuest Dissertations & Theses.
506 $a This item must not be sold to any third party vendors.
506 $a This item must not be added to any third party search indexes.
520 $a Two suites of intermediate-felsic plutonic rocks were recovered by dredges RD63 and RD64 (R/V KK81-06-26) from the northern wall of the Mariana trench near Guam, which is located in the southern part of the Izu-Bonin-Mariana (IBM) island arc system. The locations of the dredges are significant as the area contains volcanic rocks (forearc basalts and boninites) that have been pivotal in explaining processes that occur when one lithospheric plate initially begins to subduct beneath another. The plutonic rocks have been classified based on petrologic and geochemical analyses, which provides insight to their origin and evolution in context of the surrounding Mariana trench.
520 $a Based on whole rock geochemistry, these rocks (SiO2: 49-78 wt%) have island arc trace element signatures (Ba, Sr, Rb enrichment, Nb-Ta negative anomalies, U/Th enrichment), consistent with the adjacent IBM volcanics. Depletion of rare earth elements (REEs) relative to primitive mantle and excess Zr and Hf compared to the middle REEs indicate that the source of the plutonic rocks is similar to boninites and transitional boninites. Early IBM volcanic rocks define isotopic fields (Sr, Pb, Nd and Hf-isotopes) that represent different aspects of the subduction process (e.g., sediment influence, mantle provenance). The southern Mariana plutonic rocks overlap these fields, but show a clear distinction between RD63 and RD64. Modeling of the REEs, Zr and Hf shows that the plutonic suites formed via melting of boninite crust or by crystallization from a boninite-like magma rather than other sources that are found in the IBM system.
520 $a The data presented support the hypothesis that the plutonic rocks from RD63 and RD64 are products of subduction initiation and are likely pieces of middle crust in the forearc exposed at the surface by faulting and serpentine mudvolcanoes. Their existence shows that intermediate-felsic crust may form very early in the history of an intra-oceanic island arc system. Plutonic rocks with similar formation histories may exist in obducted suprasubduction zone ophiolites and would be evidence that felsic-intermediate forearc plutonics are eventually accreted to the continents.
590 $a School code: 1023.
650 4 $a Geochemistry. $3 539092
650 4 $a Geology. $3 516570
690 $a 0996
690 $a 0372
710 2 $a Florida International University. $b Geosciences. $3 2122860
773 0 $t Dissertation Abstracts International $g 75-12B(E).
790 $a 1023
791 $a Ph.D.
792 $a 2014
793 $a English
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3632526