Elemental and Sr-Nd-Pb isotopic geochemistry of the most recent   Quaternary volcanism in the Erzincan Basin, Eastern Turkey: framework   for the evaluation of basalt-lower crust interaction

doi:10.1016/j.lithos.2008.06.008

CORC > 北京大学 > 地球与空间科学学院

	Elemental and Sr-Nd-Pb isotopic geochemistry of the most recent Quaternary volcanism in the Erzincan Basin, Eastern Turkey: framework for the evaluation of basalt-lower crust interaction
	Karsli, Orhan ; Chen, Bin ; Uysal, Ibrahim ; Aydin, Faruk ; Wijbrans, Jan R. ; Kandemir, Raif
刊名	lithos
	2008
关键词	Sr-Nd-Pb isotopes Rhyolites Basalt-crust interactions Rhyolite domes Quaternary Erzincan Volcanics North Anatolian Fault Zone Eastern Turkey STRIKE-SLIP TECTONICS CALC-ALKALINE CENTRAL ANATOLIA TRACE-ELEMENT EVOLUTION ORIGIN ROCKS EXTENSION GENESIS BENEATH
DOI	10.1016/j.lithos.2008.06.008
英文摘要	Whole-rock geochemical and Sr, Nd and Pb isotope data are presented for a representative suite of the Quaternary Erzincan Volcanics (QEV) from the Erzincan basin (EB) along the North Anatolian Fault Zone, aiming to understand their origin and implications for basalt-lower crust interaction. Unspiked K-Ar and (40)Ar/(39)Ar dating of dome lavas from the QEVs yielded ages of 102 +/- 2 to 1061 +/- 88 ka. The QEVs range from high-K low silica trachy-andesite to rhyolite in composition, with rhyolite volumetrically the most abundant. All rocks show high-K calc-alkaline affinity, a geochemical signature common to many post-collisional magmas. They are characterized by enrichment in LILE (Rb, Ba, K, Th) and LREE ((La/Yb)(CN) = 3-33), with pronounced depletion of HFSE. All lavas show negligible or small negative Eu anomalies in the andesitic to dacitic and strong Eu anomalies in the rhyolitic samples. These rocks have relatively low (87)Sr/(86)Sr = 0.70404-0.70587 and slightly depleted Nd isotopic compositions (epsilon(Nd) from -0.9 to 2.8), with significantly varied Mg# ranging from 2 to 53. Pb isotopic compositions [(206)Pb/(204)Pb = 18.90-19.02, (207)Pb/(204)Pb = 15.64-15.70, (208)Pb/(204)Pb = 38.91-39.97] reveal an enriched source signature, which implies that some portions of metasomatized lithospheric mantle could have contributed to their genesis. The isotopic ratios and chemical features along with the textural and compositional disequilibrium of the plagioclases and amphiboles suggest that mixing of mafic and felsic magmas played an important role in the magma genesis. A possible scenario for the genesis of these volcanic rocks is that basaltic magma formed as a result of partial melting of a subcontinental lithospheric mantle source responding to a possible upwelling of asthenospheric mantle which was caused by the extension produced by strike-slip tectonics. Underplating of these high-temperature basaltic magmas sparked partial fusion of a juvenile lower continental crust producing felsic melts; then magma mixing between basaltic and the felsic magmas followed. Fractional crystallization, with minor amounts crustal contamination could have played an important role in the evolution of magma. Modelling based on Sr and Nd isotope data shows that less than 10% of a basic magma and about 90% of juvenile lower continental crustal material was involved in the generation of the QEVs in a pull-apart basin along the North Anatolian Fault Zone. (C) 2008 Elsevier B.V. All rights reserved.; Geochemistry & Geophysics; Mineralogy; SCI(E); 0; ARTICLE; 1-2; 55-70; 106
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/248143]
专题	地球与空间科学学院
推荐引用方式 GB/T 7714	Karsli, Orhan,Chen, Bin,Uysal, Ibrahim,et al. Elemental and Sr-Nd-Pb isotopic geochemistry of the most recent Quaternary volcanism in the Erzincan Basin, Eastern Turkey: framework for the evaluation of basalt-lower crust interaction[J]. lithos,2008.
APA	Karsli, Orhan,Chen, Bin,Uysal, Ibrahim,Aydin, Faruk,Wijbrans, Jan R.,&Kandemir, Raif.(2008).Elemental and Sr-Nd-Pb isotopic geochemistry of the most recent Quaternary volcanism in the Erzincan Basin, Eastern Turkey: framework for the evaluation of basalt-lower crust interaction.lithos.
MLA	Karsli, Orhan,et al."Elemental and Sr-Nd-Pb isotopic geochemistry of the most recent Quaternary volcanism in the Erzincan Basin, Eastern Turkey: framework for the evaluation of basalt-lower crust interaction".lithos (2008).