Geochemical, age, and isotopic constraints on the location of the Sino-Korean/Yangtze Suture and evolution of the Northern Dabie Complex, east central China

被引:152
作者
Bryant, DL
Ayers, JC
Gao, S
Miller, CF
Zhang, HF
机构
[1] Vanderbilt Univ, Dept Earth & Environm Sci, Nashville, TN 37235 USA
[2] China Univ Geosci, Fac Earth Sci, Wuhan 430074, Peoples R China
[3] NW Univ Xian, Dept Geol, Key Lab Continental Dynam, Xian 710069, Peoples R China
关键词
metamorphism; monazite; zircon; geochronology; Dabie Mountains; ion probe dating;
D O I
10.1130/B25302.2
中图分类号
P [天文学、地球科学];
学科分类号
07 ;
摘要
The Northern Dabie Complex in east central China lies between the Sino-Korean plate to the north and the Yangtze plate to the south. The Northern Dabie Complex has been variously proposed to represent a Paleozoic magmatic arc on the Sino-Korean plate, an exhumed piece of subducted Yangtze plate crust, or crust produced almost entirely by Cretaceous extension-related magmatism. Trace element compositions of Northern Dabie Complex orthogneisses and granites show arc signatures similar to those of ultra-high-pressure rocks in the central Dabie, but no mineralogical evidence of ultra-high-pressure metamorphism is present in the samples investigated here. Field relationships, textures, major and trace element compositions, and ion microprobe U-Pb zircon protolith crystallization ages reveal three distinct types of gneiss: diorite gneiss xenoliths (770 +/- 26 Ma, 95% confidence limit), those within first-genation highly deformed migmatitic grey gneisses (747 +/- 14 Ma), and those cross-cut by second-generation Cretaceous weakly foliated felsic gneisses (127 +/- 4 Ma). Unfoliated Cretaceous granites (117 +/- 11 Ma, monazite Th-Pb age = 117 +/- 1 Ma) intrude second-generation gneisses. Cretaceous second-generation gneisses and granites yield zircon inheritance ages of ca. 2 Ga, 700-800 Ma, and (rarely) 227-271 Ma, indicating that the Northern Dabie Complex is not simply a Cretaceous extensional terrane. The 700-800 Ma zircon ages are similar to those of granitic gneisses from the central ultra-high-pressure zone (698 +/- 47 Ma) and are characteristic of the Yangtze craton. epsilon(Nd) values suggest that Cretaceous rocks in the Northern Dabie Complex formed by partial melting of basement with very low epsilon(Nd) and not by melting of first-generation or diorite gneisses. Nd-depleted mantle model ages are consistent with the time of formation of the Yangtze craton at 1.4-2.5 Ga. The Northern Dabie Complex is interpreted to be an extension of the Yangtze craton that was un-affected by ultra-high-pressure metamorphism. The Sino-Korean/Yangtze suture must lie to the north of the Northern Dabie Complex.
引用
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页码:698 / 717
页数:20
相关论文
共 57 条
[1]  
[Anonymous], ISOPLOT EX VERSION 2
[2]  
[Anonymous], 1993, LONGMAN GEOCHEMISTRY
[3]   Constraints on timing of peak and retrograde metamorphism in the Dabie Shan Ultrahigh-Pressure Metamorphic Belt, east-central China, using U-Th-Pb dating of zircon and monazite [J].
Ayers, JC ;
Dunkle, S ;
Gao, S ;
Miller, CF .
CHEMICAL GEOLOGY, 2002, 186 (3-4) :315-331
[4]  
BRYANT DL, 2002, THESIS VANDERBILT U
[5]   Petrogenesis of Mesozoic granitoids in the dabie UHP complex, central china: trace element and Nd-Sr isotope evidence [J].
Chen, B ;
Jahn, BM ;
Wei, CJ .
LITHOS, 2002, 60 (1-2) :67-88
[6]  
Chen DG, 2000, ACTA PETROL SIN, V16, P199
[7]   Crustal evolution of southeastern China: Nd and Sr isotopic evidence [J].
Chen, JF ;
Jahn, BM .
TECTONOPHYSICS, 1998, 284 (1-2) :101-133
[8]   Post-collisional transition from calc-alkaline to alkaline volcanism during the Neogene in Oranie (Algeria): magmatic expression of a slab breakoff [J].
Coulon, C ;
Megartsi, M ;
Fourcade, S ;
Maury, RC ;
Bellon, H ;
Louni-Hacini, A ;
Cotten, J ;
Coutelle, A ;
Hermitte, D .
LITHOS, 2002, 62 (3-4) :87-110
[9]  
DAOGONG C, 2000, ACTA PETROL SIN, V16, P199
[10]   Re-Os evidence for replacement of ancient mantle lithosphere beneath the North China craton [J].
Gao, S ;
Rudnick, RL ;
Carlson, RW ;
McDonough, WF ;
Liu, YS .
EARTH AND PLANETARY SCIENCE LETTERS, 2002, 198 (3-4) :307-322