238U230Th disequilibria, magma petrogenesis, and flux rates beneath the depleted Tonga-Kermadec island arc

Turner, Simon; Hawkesworth, Chris J.; Rogers, Nick; Bartlett, J.; Worthington, T.J.; Hergt, Janet; Pearce, Julian A.; Smith, I. E.

doi:10.1016/s0016-7037(97)00281-0

Cited by 371 publications

(335 citation statements)

References 82 publications

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“…The sediment veneer on the incoming Pacific Plate, changes in thickness and composition from B200 m of pelagic sediments near B25°S (that is, DSDP Site 204; for example, ref. 24; Fig. 1) to Z500 m of predominantly terrigeneous sediments near B36°S (ref.…”

Section: Resultsmentioning

confidence: 99%

Subduction of the oceanic Hikurangi Plateau and its impact on the Kermadec arc

et al. 2014

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Large igneous province subduction is a rare process on Earth. A modern example is the subduction of the oceanic Hikurangi Plateau beneath the southern Kermadec arc, offshore New Zealand. This segment of the arc has the largest total lava volume erupted and the highest volcano density of the entire Kermadec arc. Here we show that Kermadec arc lavas south of B32°S have elevated Pb and Sr and low Nd isotope ratios, which argues, together with increasing seafloor depth, forearc retreat and crustal thinning, for initial Hikurangi Plateau-Kermadec arc collision B250 km north of its present position. The combined data set indicates that a much larger portion of the Hikurangi Plateau (the missing Ontong Java Nui piece) than previously believed has already been subducted. Oblique plate convergence caused southward migration of the thickened and buoyant oceanic plateau crust, creating a buoyant 'Hikurangi' mélange beneath the Moho that interacts with ascending arc melts.

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Section: Resultsmentioning

confidence: 99%

Subduction of the oceanic Hikurangi Plateau and its impact on the Kermadec arc

et al. 2014

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“…Both were sampled during the R/V Tangaroa NZAPLUME III expedition in 2004. Lavas from Ata, however, have elevated (La/Sm) N Z0.9, indicating either a lower degree of partial melting, or a local source enrichment in the mantle wedge 26 . Back-arc lavas show similar elevations in (La/Sm) N , which increases from B0.6 at the eastern Lau-spreading centre, to Z1.0 at the southern tip of the Valu Fa ridge (for example, refs 33,35-37).…”

Section: Resultsmentioning

confidence: 98%

“…therefore, be alternatively explained through partial melting of a locally enriched mantle with ocean-island-type affinities ( ± a sedimentary component), similar to the interpretation of Todd et al 41 The lack of a Louisville signature in the lavas north of Ata suggests that such a signature can only be detected in more recent lavas in the vicinity of the subducting Louisville seamounts. There is uncertainty about the age of Ata Island but, based on moderate 238 U excess in Ata lavas and the lack of recent activity, it could be a few hundred thousand years old 26 (Fig. 3a-d) 41 .…”

Section: Resultsmentioning

confidence: 99%

“…Based on U-Th and 231 Pa-235 U isotope data on lavas from Tonga-Kermadec arc-front volcanoes and the southern Lau Basin, it has been inferred that the time elapsed from fluid addition from the subducting slab to eruption was between B30 kyr and 60 kyr (for example, refs 26,38,55). However, three studies on Tongan-Kermadec arc lavas estimated an even faster fluid addition time of o8 kyr [56][57][58] .…”

Section: Discussionmentioning

confidence: 99%

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Louisville seamount subduction and its implication on mantle flow beneath the central Tonga–Kermadec arc

et al. 2013

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“…Significant components of arc magmas are derived from mantle wedge (Hochstaedter, Kepezhinskas, Defant, Drummond, & Koloskov, 1996), metasomatised by fluids (from altered oceanic crust or subducted sediments) (Elliott et al, 1997;Smith, Holm, & Thirlwall, 2008;Tatsumi et al, 1986;Turner et al, 1997). Arc magmas result from the partial melting of the metasomatised lithospheric mantle with the effect of the subducted oceanic crust and fluids (Greene, Debari, Kelemen, Blusztajn, & Clift, 2006).…”

Section: Partial Meltingmentioning

confidence: 99%

Subduction-related Late Cretaceous high-K volcanism in the Central Pontides orogenic belt: constraints on geodynamic implications

Aydınçakır

2016

Geodinamica Acta

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Mineral chemistry, major and trace elements, 40 Ar/ 39 Ar age and Sr-Nd-Pb isotopic data are presented for the Late Cretaceous Hamsilos volcanic rocks in the Central Pontides, Turkey. The Hamsilos volcanic rocks mainly consist of basalt, andesite and associated pyroclastics (volcanic breccia, vitric tuff and crystal tuff). They display shoshonitic and high-K calc-alkaline affinities. The shoshonitic rocks contain plagioclase, clinopyroxene, alkali feldspar, phlogopite, analcime, sanidine, olivine, apatite and titanomagnetite, whereas the high-K calc-alkaline rocks contain plagioclase, clinopyroxene, orthopyroxene, magnetite / titanomagnetite in microgranular porphyritic, hyalo-microlitic porphyritic and glomeroporphyritic matrix. Mineral chemistry data reveal that the pressure condition of the clinopyroxene crystallisation for the shoshonitic rocks are between 1.4 and 6.3 kbar corresponds to 6-18-km depth and the high-K calc-alkaline rocks are between 5 and 12 km. 40 Ar/ 39 Ar age data changing between 72 ± .5 Ma and 79.0 ± .3 Ma (Campanian) were determined for the Late Cretaceous Hamsilos volcanic rocks, contemporaneous with the subduction of the Neo-Tethyan Ocean beneath the Pontides. The studied volcanic rocks were enriched in the large-ion lithophile and light rare earth element contents, with pronounced depletion in the contents of high-field-strength elements. Chondrite-normalised rare earth element patterns (La N /Lu N = 6-17) show low to medium enrichment, indicating similar sources of the rock suite. Pb/ 204 Pb values between 37.839 and 38.427. The main solidification processes involved in the evolution of the volcanic rocks consist of fractional crystallisation, with minor amounts of crustal contamination ± magma mixing. According to geochemical evidence, the shoshonitic melts in the Hamsilos volcanic rocks were possibly derived from the low degree of partial melting of a subcontinental lithospheric mantle (SCLM), while the high-K calc-alkaline melts were derived from relatively high degree of partial melting of SCLM that was enriched by fluids and/or sediments from a subduction of oceanic crust.

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238U230Th disequilibria, magma petrogenesis, and flux rates beneath the depleted Tonga-Kermadec island arc

Cited by 371 publications

References 82 publications

Subduction of the oceanic Hikurangi Plateau and its impact on the Kermadec arc

Subduction of the oceanic Hikurangi Plateau and its impact on the Kermadec arc

Louisville seamount subduction and its implication on mantle flow beneath the central Tonga–Kermadec arc

Subduction-related Late Cretaceous high-K volcanism in the Central Pontides orogenic belt: constraints on geodynamic implications

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