Precise Re-Os Dating of Molybdenite from the Northern Dabie Molybdenum Belt in Central China and its Geodynamic Implications

2012 ◽  
Vol 535-537 ◽  
pp. 1035-1038
Author(s):  
Jun Ping Li ◽  
Yong Feng Li ◽  
Ke Jia Xie
Keyword(s):  
North China ◽  
Central China ◽  
Metamorphic Belt ◽  
Dabie Orogen ◽  
East Central ◽  
The North ◽  
Metallogenic Belt ◽  
Vein Type ◽  
Granite Porphyries ◽  
Granitoid Intrusions

The Dabie orogen of east-central China marks the boundary between the North China and Yangtze Cratons, and is characterized by juxtaposition of the ~400Ma Tongbai metamorphic belt and the ~220Ma South Qinling-Dabie metamorphic belt. The Triassic collision between the North China and Yangtze Cratons which generated numerous granitoid intrusions such as the Shangcheng, Xingxian and Lingshan intrusions, and other small stocks, such as Tangjiaping, Dayinjian, Mushan and so on. Those shallow-emplaced granite porphyries are closely related to porphyry-skarn Mo and Mo-W deposites, forming the Dabie molybdenum metallogenic belt. Molybdenum deposits occur in the endo- and exocontact zones of the porphyry, include with three major types of Mo mineral systems, i.e., porphyry, less porphyry-skarn and vein-type. The ore-forming ages of the molybdenum deposits in Dabie area are mainly cluster 127.8±0.9~113.1±7.9Ma. The pulse is the product of the transformation of the tectonic regime from NS- to nearly EW-directions in East China.

Zircon U–Pb ages, major and trace elements, and Hf isotope characteristics of the Tiantangzhai granites in the North Dabie orogen, Central China: tectonic implications

2013 ◽  
Vol 151 (5) ◽  
pp. 916-937 ◽  
Author(s):  
XIN DENG ◽  
KUNGUANG YANG ◽  
ALI POLAT ◽  
TIMOTHY M. KUSKY ◽  
KAIBIN WU
Keyword(s):  
Partial Melting ◽  
Eastern China ◽  
Major And Trace Elements ◽  
Central China ◽  
Dabie Orogen ◽  
Crustal Rocks ◽  
The North ◽  
Granitic Magmatism ◽  
Two Peaks ◽  
Lower Crustal

AbstractCretaceous granites are widespread in the North Dabie orogen, Central China, but their emplacement sequence and mechanism are poorly known. The Tiantangzhai Complex in the North Dabie Complex is the largest Cretaceous granitic suite consisting of six individual intrusions. In this study, zircon U–Pb ages are used to constrain the crystallization and protolith ages of these intrusions. The Shigujian granite is a syn-tectonic intrusion with an age of 141 Ma. This granite was emplaced under a compressional regime. Oscillatory rims of zircons have yielded two peaks at 137±1 Ma and 125±1 Ma. The 137±1 Ma peak represents the beginning of orogenic extension and tectonic collapse, whereas the 125±1 Ma peak represents widespread granitic magmatism. Zircon cores have yielded concordant ages between 812 and 804 Ma, which indicate a crystallization age for the protolith. The Tiantangzhai granites show relatively high Sr contents and high La/Yb and Sr/Y ratios. The Shigujian granite has positive Eu anomalies resulting from partial melting of a plagioclase-rich source in an over-thickened crust. Correspondingly, in situ Lu–Hf analyses from zircons yield high negative εHf(t) values from −24.8 to −26.6, with two-stage Hf model ages from 2748±34 to 2864±40 Ma, suggesting that the magmas were dominantly derived from partial melting of middle to lower crustal rocks. The Dabie orogen underwent pervasive NW–SE extension at the beginning of the early Cretaceous associated with subduction of the Palaeo-Pacific plate beneath eastern China.

Ultrahigh-pressure eclogite transformed from mafic granulite in the Dabie orogen, east-central China

2007 ◽  
Vol 25 (9) ◽  
pp. 975-989 ◽  
Author(s):  
Y.-C. LIU ◽  
S.-G. LI ◽  
X.-F. GU ◽  
S.-T. XU ◽  
G.-B. CHEN
Keyword(s):  
Central China ◽  
Mafic Granulite ◽  
Ultrahigh Pressure ◽  
Dabie Orogen ◽  
East Central

scholarly journals The Metallogenic Setting of the Jiangjiatun Mo Deposit, North China: Constraints from a Combined Zircon U–Pb and Molybdenite Re–Os Isotopic Study

Minerals ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 723 ◽  
Author(s):  
Ming Li ◽  
Xin Zhang ◽  
Liang Han ◽  
En-Pu Gong ◽  
Guo-Guang Wang
Keyword(s):  
North China Craton ◽  
Late Jurassic ◽  
North China ◽  
Pacific Plate ◽  
Late Triassic ◽  
Isotopic Study ◽  
The North ◽  
Tectonic Transition ◽  
Isotopic System ◽  
Metallogenic Belt

The Jiangjiatun Mo deposit is a recently discovered molybdenum deposit in the easternmost area of the Yan-Liao metallogenic belt, North China Craton. Quartz vein-type Mo mineralization at Jiangjiatun is associated with the granitic porphyry stock. In this study, we performed a combined zircon U–Pb and molybdenite Re-Os dating study on the Jiangjiatun Mo deposit to constrain its mineralization age and metallogenic setting. Laser ablation inductively coupled mass spectrometry (LA-ICP-MS) zircon U–Pb analyses suggest that the granitic porphyry was formed during the Late Jurassic, with a weighted mean 206Pb/238U age of 154 ± 1 Ma (2σ). Seven molybdenite samples from the Jiangjiatun deposit yield a 187Re–187Os isochron age of 157.5 ± 0.5 Ma (2σ). The discrepancy between the U–Pb and Re–Os ages may be explained (1) by the “2 sigma” measurement uncertainty, or (2) by the different closure temperature of the Re–Os isotopic system of molybdenite and the U–Pb isotopic system of zircon. Even though there is a small difference between the zircon U–Pb and molybdenite Re–Os ages, we can clearly identify a Late Jurassic Mo mineralization event at Jiangjiatun in the easternmost area of the Yan-Liao metallogenic belt. The moderate Re concentrations (13 to 73 ppm) in molybdenite from the Jiangjiatun Mo deposit are indicative of the involvement of the mantle materials into the Mo mineralization. The Jiangjiatun Mo deposit is likely the result of the subduction of the paleo-Pacific plate beneath the North China Craton during the Late Jurassic. Combined with the available published regional robust geochronological data, we proposed that the Mo mineralization in the Yan-Liao belt is in good agreement with the tectonic transition from Late Triassic post-collision extensional setting due to the closure of the paleo-Asian ocean to the Yanshanian (J–K1) continental arc setting in response to the subduction of the paleo-Pacific Plate. The study highlights that regional mineralization may provide an excellent constraint on tectonic change.

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