The Tectonic Background of Basement Metamorphic Rocks and Its Relationship to Uranium Source Layer, Xiangshan Uranium Ore Field

DOI

10.2991/aeece-16.2016.35How to use a DOI?

Keywords

Qingbaikou system; Remnant ocean; Uranium source layer; Xiang shan

Abstract

The geochemistry of metamorphic sedimentary rocks from Qingbaikou system in Xiangshan area indicate that : the Al2O3/ SiO2 is 0.13~0.23, equal to or slightly lower than the standard greywacke. In" REE/10-6-La/Yb" diagram, the investment point is in Sandy Rock and greywacke range, indicating that the original rock of metamorphic rocks are mainly medium maturity sandstone or graywacke. TFe2O3+MgO is 12.6% ~ 9.78%, between the island arc and active continental margin type sandstone composition. The "Hf-La/Th" and "Fe2O3+MgO and TiO2 and Al2O3/SiO2" diagram, indicates they formed in active continental margin or island arc related sedimentary basin. Previous studies show that in the 855 ~ 826Ma between the Cathaysian plate and the Yangtze plate has completed the splice of the eastern section, a large amount of S type granites formed in the process, which predates the basement metamorphic sedimentary rock formation age (810~806Ma). S type granite in this period are mainly distributed in the southeastern margin of the Yangtze plate , none in the Cathaysian plate area, but Xiangshan metasedimentary rocks exist a lot of magmatic zircons in this period, illustrating that in the the two plates subduction process, Cathaysian plate edge early formed island arc or back arc basin, then gradually evolved into remnant ocean basin, began to receive from the Yangtze plate terrigenous clastic. Metamorphic sedimentary rocks and volcanic basement intrusive have similar REE chondrite distribution pattern, but Pb-Sr-Nd isotope values and Nd model ages (volcanic intrusive complex of T2DM is 1.66Ga in average, and metasedimentary rocks is 2.17Ga.)are different. In the "t(Ma)- Nd(T)" and "143Nd/144Nd-1/Nd(10-6)" diagram and Pb isotope growth curve, the two cast in different regions, indicating that there are not too much relationship between them. In the deep of Xiangshan, there should be a source of uranium storage, but not basement metamorphic rocks, in the diagenesis process, the rock magma and the reservoir happened mixing together and come into being the complex rock mass.

Copyright

© 2016, the Authors. Published by Atlantis Press.

Open Access

This is an open access article distributed under the CC BY-NC license (http://creativecommons.org/licenses/by-nc/4.0/).

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TY  - CONF
AU  - Xiaoliang Zhang
AU  - Qingkun Yang
AU  - Yang Zeng
AU  - Hongjian Qu
AU  - Wanpeng Zhou
AU  - Zehuang Rao
PY  - 2016/07
DA  - 2016/07
TI  - The Tectonic Background of Basement Metamorphic Rocks and Its Relationship to Uranium Source Layer, Xiangshan Uranium Ore Field
BT  - Proceedings of the 2016 2nd International Conference on Advances in Energy, Environment and Chemical Engineering (AEECE 2016)
PB  - Atlantis Press
SP  - 158
EP  - 168
SN  - 2352-5401
UR  - https://doi.org/10.2991/aeece-16.2016.35
DO  - 10.2991/aeece-16.2016.35
ID  - Zhang2016/07
ER  -