Please use this identifier to cite or link to this item: https://hdl.handle.net/2440/116299
Citations
Scopus Web of Science® Altmetric
?
?
Type: Journal article
Title: New data of the Bayan Obo Fe-REE-Nb deposit, Inner Mongolia: implications for ore genesis
Author: Lai, X.
Yang, X.
Santosh, M.
Liu, Y.
Ling, M.
Citation: Precambrian Research, 2015; 263:108-122
Publisher: Elsevier
Issue Date: 2015
ISSN: 0301-9268
1872-7433
Statement of
Responsibility: 
Xiaodong Lai, Xiaoyong Yang, M. Santosh, Yulong Liu, Mingxing Ling
Abstract: The Bayan Obo deposit in the Inner Mongolia, North China Craton, is the largest rare-earth element (REE) resource in the world. The deposit is hosted in Mesoproterozoic sediments of the Bayan Obo Group, the lithological sequence of which has been divided into seventeen units (H₁–H₁₇). The REE mineralization is mainly concentrated in the H8 dolomite unit, and therefore the depositional age of this unit is important in addressing the debate over the genesis of the REE–Fe–Nb ore deposit. Here we present U–Pb and Hf model ages of zircons from the adjacent H9 slate. Our data suggest that the H9 slate formed at 1505 ± 12 Ma and the H8 dolomite was deposited during the Mesoproterozoic. We also present Ar–Ar ages of riebeckite in veins cutting the H8 dolomite and biotite in the ore bodies which show 389.5 ± 3.0 Ma and 289.1 ± 1.8 Ma, respectively. The U–Pb measurements from overgrowth zircon in H9 slate give an age of 518.8 ± 7.5 Ma. These new age data indicate that the Bayan Obo deposit was disturbed during thermal events at 520 Ma to 390 Ma, generating a second phase of REE–Nb mineralization. The δ⁷Li values of the REE mineralized dolomite are similar to those of carbonatite dykes. Combined with ɛNd features, we provide geochemical evidences that REE mineralized dolomite has undergone fluid interaction. Results reveal that the carbonatite magmatism occurred within the Bayan Obo rift at ca. 1.2 Ga, provided the primary source for REE–Nb mineralization or to fertilize the Bayan Obo crust, and the later was remobilized during the Caledonian to generate the second phase of mineralization within a convergent plate margin regime.
Keywords: U–Pb geochronology; Ar–Ar dating; Hf isotope; Li isotope; Bayan Obo Fe–REE–Nb deposit; North China Craton
Rights: © 2015 Elsevier B.V. All rights reserved.
DOI: 10.1016/j.precamres.2015.03.013
Published version: http://dx.doi.org/10.1016/j.precamres.2015.03.013
Appears in Collections:Aurora harvest 8
Geology & Geophysics publications

Files in This Item:
There are no files associated with this item.


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.