Early Cretaceous high Mg-# and high Sr/Y clinopyroxene-bearing diorite;in the southeast Gangdese batholith, Southern Tibet.

	Early Cretaceous high Mg-# and high Sr/Y clinopyroxene-bearing diorite;in the southeast Gangdese batholith, Southern Tibet.
	Wang Li 3; Zeng LingSen ; Gao LiE ; Chen ZhenYu 1
刊名	ACTA PETROLOGICA SINICA
	2013
卷号	29 期号:6 页码:1977-1994
关键词	Gangdese batholith Diorite Zircon U-Pb dating Zircon Hf isotope geochemistry Emplacement depth
ISSN号	1000-0569
英文摘要	Field investigations and SHRIMP zircon U-Pb dating indicate that a suite diorite that intruded into gneisses of granodioritic composition north of Langxian of the southern Gangdese belt, formed at 121. 8 +/- 1. 5Ma. This Early Cretaceous suite contains magmatic epidote and clinopyroxene. Whole rock geochemical data and zircon Hf isotope data of this suite of diorite show the following characteristics : (1) low SiO2 (54. 9% similar to 55. 4%), high Al2O3 (17. 7% similar to 17. 9%) and high Mg-# (65. 3 similar to 66. 1); (2) relatively high Na2O/K2O (>2. 5), indicating that they were of granite rich in sodium; (3) enriched in LREE, depleted in HREE, nearly Plat distribution patterns for elements from Ho to Yb with (Ho/Yb)(N) = 0. 93 similar to 1. 07, and weak negative Eu anomalies with Eu/Eu* = 0.88 similar to 0. 91; (4) relatively high Sr (488 x 10(-6) similar to 500 x 10(-6)) and Ba (176 x 10(-6) similar to 181 x 10(-6)), high Sr/Y (37.5 similar to 41.7) and low La/Yb (7. 6 similar to 9. 8); (5) relatively high zircon epsilon(Hf)(t) values (+3. 4 similar to +6. 9); and (6) depleted in the HFSE, but relatively enriched in garnet compatible elements (Sc, Y and HREE) as well as mantle compatible elements (Cr, Ni and Co). These geochemical features and mineral assemblages indicate that they were hydrous magma derived from the partial melting of fluid metasomatised mantle wedge during the northward subduction of the Neo-Tethyan slab. Emplace depths for the Early Cretaceous diorite as well as the Early Carboniferous granodiorite estimated by Al-in-hornblende geobarometer indicate that they were emplaced at similar to 13km and similar to 21km, respectively, which in turn yields a long term exhumation rate of similar to 0. 04mm/yr.
学科主题	火成岩岩石学
WOS关键词	U-PB GEOCHRONOLOGY ; EMPIRICAL IGNEOUS GEOBAROMETER ; IN-HORNBLENDE ; BAROMETER ; VOLCANIC-ROCKS ; MAGMATIC EPIDOTE ; ARC MAGMAS ; EXPERIMENTAL ; CALIBRATION ; SUBDUCTED LITHOSPHERE ; CONTINENTAL COLLISION ; TECTONIC ; IMPLICATIONS
WOS研究方向	Geology
语种	中文
出版者	SCIENCE PRESS
WOS记录号	WOS:000322427000009
内容类型	期刊论文
源URL	[http://119.78.100.197/handle/2HKVOGP0/40165]
专题	中国地质科学院地质研究所
作者单位	1.Chinese Acad Geol Sci, Inst Geol, State Key Lab Continental Tecton & Dynam, Beijing 100037, Peoples R China. 2.Chinese Acad Geol Sci, Inst Mineral Resources, Beijing 100037, Peoples R China. 3.中国地质科学院地质研究所
推荐引用方式 GB/T 7714	Wang Li,Zeng LingSen,Gao LiE,et al. Early Cretaceous high Mg-# and high Sr/Y clinopyroxene-bearing diorite;in the southeast Gangdese batholith, Southern Tibet.[J]. ACTA PETROLOGICA SINICA,2013,29(6):1977-1994.
APA	Wang Li,Zeng LingSen,Gao LiE,&Chen ZhenYu.(2013).Early Cretaceous high Mg-# and high Sr/Y clinopyroxene-bearing diorite;in the southeast Gangdese batholith, Southern Tibet..ACTA PETROLOGICA SINICA,29(6),1977-1994.
MLA	Wang Li,et al."Early Cretaceous high Mg-# and high Sr/Y clinopyroxene-bearing diorite;in the southeast Gangdese batholith, Southern Tibet.".ACTA PETROLOGICA SINICA 29.6(2013):1977-1994.