Three-step continental-crust growth from subduction accretion and underplating, through intermediary differentiation, to granitoid production

doi:10.1007/s00531-008-0299-y

	Three-step continental-crust growth from subduction accretion and underplating, through intermediary differentiation, to granitoid production
	Liu, Wei 1; Pan, Xiao-Fei 1; Liu, Dun-Yi 2; Chen, Zhen-Yu 3
刊名	INTERNATIONAL JOURNAL OF EARTH SCIENCES
	2009-09-01
卷号	98 期号:6 页码:1413-1439
关键词	Continental crustal growth Inherited/antecrystal zircon from juvenile rocks Intermediary differentiation Subducted oceanic crust Underplating
ISSN号	1437-3254
DOI	10.1007/s00531-008-0299-y
文献子类	Article
英文摘要	Sensitive high-resolution ion microprobe (SHRIMP) U-Pb dating, laser-ablation multi-collector IC-PMS Hf isotope and electron microprobe element analyses of inherited/antecrystal and magmatic zircons from five granitoid intrusions of Linxi area, in the southern segment of the Great Xing' an Range of China were integrated to solve continental crustal growth mechanisms. These intrusions were divided into two suites. Suites 1 and 2 are mainly granodiorite and syenogranite and correspond to magnesian and ferroan granites, respectively. SHRIMP dating establishes an Early Cretaceous (135-125 Ma) age for most Linxi granitoids and a time of similar to 146 Ma when their source rocks were generated or re-melted. However, some granitoids were generated in Early Triassic (241 Ma) and Late Jurassic (146 Ma), after their source rock experienced precursory melting episodes at 263 Ma and 165 Ma, respectively. All zircon Pb-206/U-238 ages (<300 Ma, n = 100), and high positive zircon epsilon(Hf)(t) values (n = 175) suggest juvenile source materials with an absence of Precambrian basement. Hf-Nd isotopic decoupling of Linxi granitoids suggests a source component of pelagic sediments, i.e. Paleozoic subduction accretion complexes. Zircon epsilon(Hf)(t) values (t = 263-165 Ma) form a trend sub-parallel to the depleted mantle Hf isotope evolution curve, whilst those with t = 146-125 Ma fall markedly below the latter. The first trend indicates a provenance from essentially subducted oceanic slabs. However, the abrupt epsilon(Hf)(t) decrease, together with extensive Early Cretaceous magmatism, is interpreted as reflecting mantle upwelling and resultant underplating, and exhumation of subducted oceanic slabs. Suite 1 granitoids derive mainly from subducted oceanic slabs or Paleozoic subduction accretion complex, whereas Suite 2 from underplated mafic rock and, subordinately, Paleozoic subduction accretion complex. Compositions of Suites 1 and 2 depend on the hydrous, oxidized or relatively anhydrous, reduced nature of source rocks. Among each of these five intrusions, magmatic zircons have systematically lower Hf-176/Hf-177 than inherited/antecrystal zircons. Hf isotopic and substituting element profiles through inherited/antecrystal zircons (t = 263 to similar to 146 Ma) indicate repeated low melt-fraction melting in the source region. In contrast, profiles through inherited/antecrystal and magmatic zircons (t = 146-125 Ma) reveal melting region expansion with a widening range of source compositions and increasing melt fractions. These results lead to the conclusion that continental growth in this region involved a three-step process. This included subduction accretion and repeated underplating, intermediary differentiation of juvenile rocks, and granitoid production from these differentiated rocks.
WOS关键词	METAMORPHIC CORE COMPLEX ; A-TYPE GRANITES ; NORTHERN INNER-MONGOLIA ; U-PB ISOTOPE ; LU-HF ; TECTONIC EVOLUTION ; SEDIMENTARY SYSTEM ; JIAODONG PENINSULA ; MASS-SPECTROMETRY ; DEPLETED-MANTLE
WOS研究方向	Geology
语种	英语
出版者	SPRINGER
WOS记录号	WOS:000269376400014
资助机构	National Basic Research Program of China(2007CB411302 ; National Basic Research Program of China(2007CB411302 ; National Science Foundation of China(40472056) ; National Science Foundation of China(40472056) ; Chinese Academy of Sciences(KZCX1-07-04) ; Chinese Academy of Sciences(KZCX1-07-04) ; 2001CB409803) ; 2001CB409803) ; National Basic Research Program of China(2007CB411302 ; National Basic Research Program of China(2007CB411302 ; National Science Foundation of China(40472056) ; National Science Foundation of China(40472056) ; Chinese Academy of Sciences(KZCX1-07-04) ; Chinese Academy of Sciences(KZCX1-07-04) ; 2001CB409803) ; 2001CB409803) ; National Basic Research Program of China(2007CB411302 ; National Basic Research Program of China(2007CB411302 ; National Science Foundation of China(40472056) ; National Science Foundation of China(40472056) ; Chinese Academy of Sciences(KZCX1-07-04) ; Chinese Academy of Sciences(KZCX1-07-04) ; 2001CB409803) ; 2001CB409803) ; National Basic Research Program of China(2007CB411302 ; National Basic Research Program of China(2007CB411302 ; National Science Foundation of China(40472056) ; National Science Foundation of China(40472056) ; Chinese Academy of Sciences(KZCX1-07-04) ; Chinese Academy of Sciences(KZCX1-07-04) ; 2001CB409803) ; 2001CB409803)
内容类型	期刊论文
源URL	[http://ir.iggcas.ac.cn/handle/132A11/70794]
专题	中国科学院地质与地球物理研究所
通讯作者	Liu, Wei
作者单位	1.Chinese Acad Sci, Key Lab Mineral Resources, Inst Geol & Geophys, Beijing 100029, Peoples R China 2.Chinese Acad Geol Sci, Beijing SHRIMP Ctr, Inst Geol, Beijing 100037, Peoples R China 3.Chinese Acad Geol Sci, Inst Mineral Resources, Beijing 100037, Peoples R China
推荐引用方式 GB/T 7714	Liu, Wei,Pan, Xiao-Fei,Liu, Dun-Yi,et al. Three-step continental-crust growth from subduction accretion and underplating, through intermediary differentiation, to granitoid production[J]. INTERNATIONAL JOURNAL OF EARTH SCIENCES,2009,98(6):1413-1439.
APA	Liu, Wei,Pan, Xiao-Fei,Liu, Dun-Yi,&Chen, Zhen-Yu.(2009).Three-step continental-crust growth from subduction accretion and underplating, through intermediary differentiation, to granitoid production.INTERNATIONAL JOURNAL OF EARTH SCIENCES,98(6),1413-1439.
MLA	Liu, Wei,et al."Three-step continental-crust growth from subduction accretion and underplating, through intermediary differentiation, to granitoid production".INTERNATIONAL JOURNAL OF EARTH SCIENCES 98.6(2009):1413-1439.