SIMS U-Pb Dating of Uraninite from the Guangshigou Uranium Deposit: Constraints on the Paleozoic Pegmatite-Type Uranium Mineralization in North Qinling Orogen, China
Pegmatite-type uranium mineralization occurs in the Shangdan domain of the North Qinling Orogenic Belt, representing a significant uraniferous province. The Guangshigou deposit is the largest U deposit of the district. Within the North Qinling area, a series of Caledonian granitic igneous rocks intr...
Main Authors: | , , , , , , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
MDPI AG
2021-04-01
|
Series: | Minerals |
Subjects: | |
Online Access: | https://www.mdpi.com/2075-163X/11/4/402 |
id |
doaj-4465411b582f4c61a947bb3e55279f74 |
---|---|
record_format |
Article |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Guo-Lin Guo Christophe Bonnetti Zhan-Shi Zhang Guang-Lai Li Zhao-Bin Yan Jian-Hua Wu Yong Wu Xiao-Dong Liu Bin Wu |
spellingShingle |
Guo-Lin Guo Christophe Bonnetti Zhan-Shi Zhang Guang-Lai Li Zhao-Bin Yan Jian-Hua Wu Yong Wu Xiao-Dong Liu Bin Wu SIMS U-Pb Dating of Uraninite from the Guangshigou Uranium Deposit: Constraints on the Paleozoic Pegmatite-Type Uranium Mineralization in North Qinling Orogen, China Minerals late Caledonian uraninite SIMS Guangshigou uranium mineralization North Qinling |
author_facet |
Guo-Lin Guo Christophe Bonnetti Zhan-Shi Zhang Guang-Lai Li Zhao-Bin Yan Jian-Hua Wu Yong Wu Xiao-Dong Liu Bin Wu |
author_sort |
Guo-Lin Guo |
title |
SIMS U-Pb Dating of Uraninite from the Guangshigou Uranium Deposit: Constraints on the Paleozoic Pegmatite-Type Uranium Mineralization in North Qinling Orogen, China |
title_short |
SIMS U-Pb Dating of Uraninite from the Guangshigou Uranium Deposit: Constraints on the Paleozoic Pegmatite-Type Uranium Mineralization in North Qinling Orogen, China |
title_full |
SIMS U-Pb Dating of Uraninite from the Guangshigou Uranium Deposit: Constraints on the Paleozoic Pegmatite-Type Uranium Mineralization in North Qinling Orogen, China |
title_fullStr |
SIMS U-Pb Dating of Uraninite from the Guangshigou Uranium Deposit: Constraints on the Paleozoic Pegmatite-Type Uranium Mineralization in North Qinling Orogen, China |
title_full_unstemmed |
SIMS U-Pb Dating of Uraninite from the Guangshigou Uranium Deposit: Constraints on the Paleozoic Pegmatite-Type Uranium Mineralization in North Qinling Orogen, China |
title_sort |
sims u-pb dating of uraninite from the guangshigou uranium deposit: constraints on the paleozoic pegmatite-type uranium mineralization in north qinling orogen, china |
publisher |
MDPI AG |
series |
Minerals |
issn |
2075-163X |
publishDate |
2021-04-01 |
description |
Pegmatite-type uranium mineralization occurs in the Shangdan domain of the North Qinling Orogenic Belt, representing a significant uraniferous province. The Guangshigou deposit is the largest U deposit of the district. Within the North Qinling area, a series of Caledonian granitic igneous rocks intruded the Proterozoic metamorphic rocks of the Qinling Group in two magmatic stages: (i) the Early Silurian Huichizi granite that was derived from a low degree of partial melting of thickened lower basaltic crust combined with mantle-derived materials following the subduction of the Shangdan Ocean; and (ii) the Late Silurian–Early Devonian Damaogou granite and associated pegmatites derived from the same source but emplaced in a late tectonic post-collisional extension environment. In the Guangshigou deposit, the U mineralization mainly occurs as uraninite disseminated in U-rich granitic biotite pegmatites, which formed by assimilation-fractional crystallization magmatic processes. Petrographic observations showed evidence for coeval crystallization of uraninite and other rock-forming minerals of the host pegmatite including quartz, feldspar, biotite, zircon, monazite, apatite, and xenotime. In addition, the low U/Th ratios (~19) and Th, REE, and Y enrichments characterized a magmatic origin for uraninite, which was likely derived from fractionated high-K calc-alkaline pegmatitic magma that experienced various degrees of crustal material contamination. In situ U-Pb isotopic dating performed by Secondary-Ion Mass Spectrometry (SIMS) on uraninite from the Guangshigou deposit yielded a crystallization age of 412 ± 3 Ma, which is concomitant (within errors) with the emplacement age of the host pegmatite (415 ± 2 Ma) and constrained the U ore genesis to the Early Devonian, which corresponds to the late Caledonian post-collisional extension in the North Qinling area. Uraninite then experienced various degrees of metamictization and/or post-Caledonian hydrothermal alteration characterized by an alteration rim associated with coffinite, chlorite and limonite. Finally, the characteristics of the pegmatite-related Guangshigou deposit exhibiting Th-rich uraninite which was the product of assimilation-fractional crystallization of pegmatitic magma defined a model significantly different than the one established for the world-class Rössing deposit characterized by Th-poor uraninite hosted in alaskite dykes formed by low degree of partial melting of U-rich metasediments. |
topic |
late Caledonian uraninite SIMS Guangshigou uranium mineralization North Qinling |
url |
https://www.mdpi.com/2075-163X/11/4/402 |
work_keys_str_mv |
AT guolinguo simsupbdatingofuraninitefromtheguangshigouuraniumdepositconstraintsonthepaleozoicpegmatitetypeuraniummineralizationinnorthqinlingorogenchina AT christophebonnetti simsupbdatingofuraninitefromtheguangshigouuraniumdepositconstraintsonthepaleozoicpegmatitetypeuraniummineralizationinnorthqinlingorogenchina AT zhanshizhang simsupbdatingofuraninitefromtheguangshigouuraniumdepositconstraintsonthepaleozoicpegmatitetypeuraniummineralizationinnorthqinlingorogenchina AT guanglaili simsupbdatingofuraninitefromtheguangshigouuraniumdepositconstraintsonthepaleozoicpegmatitetypeuraniummineralizationinnorthqinlingorogenchina AT zhaobinyan simsupbdatingofuraninitefromtheguangshigouuraniumdepositconstraintsonthepaleozoicpegmatitetypeuraniummineralizationinnorthqinlingorogenchina AT jianhuawu simsupbdatingofuraninitefromtheguangshigouuraniumdepositconstraintsonthepaleozoicpegmatitetypeuraniummineralizationinnorthqinlingorogenchina AT yongwu simsupbdatingofuraninitefromtheguangshigouuraniumdepositconstraintsonthepaleozoicpegmatitetypeuraniummineralizationinnorthqinlingorogenchina AT xiaodongliu simsupbdatingofuraninitefromtheguangshigouuraniumdepositconstraintsonthepaleozoicpegmatitetypeuraniummineralizationinnorthqinlingorogenchina AT binwu simsupbdatingofuraninitefromtheguangshigouuraniumdepositconstraintsonthepaleozoicpegmatitetypeuraniummineralizationinnorthqinlingorogenchina |
_version_ |
1721530456146444288 |
spelling |
doaj-4465411b582f4c61a947bb3e55279f742021-04-11T23:01:52ZengMDPI AGMinerals2075-163X2021-04-011140240210.3390/min11040402SIMS U-Pb Dating of Uraninite from the Guangshigou Uranium Deposit: Constraints on the Paleozoic Pegmatite-Type Uranium Mineralization in North Qinling Orogen, ChinaGuo-Lin Guo0Christophe Bonnetti1Zhan-Shi Zhang2Guang-Lai Li3Zhao-Bin Yan4Jian-Hua Wu5Yong Wu6Xiao-Dong Liu7Bin Wu8State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, ChinaState Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, ChinaState Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, ChinaState Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, ChinaState Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, ChinaState Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, ChinaCNNC Key Laboratory of Uranium Resources Exploration and Evaluation Technology, Beijing Research Institute of Uranium Geology, Beijing 100029, ChinaState Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, ChinaState Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, ChinaPegmatite-type uranium mineralization occurs in the Shangdan domain of the North Qinling Orogenic Belt, representing a significant uraniferous province. The Guangshigou deposit is the largest U deposit of the district. Within the North Qinling area, a series of Caledonian granitic igneous rocks intruded the Proterozoic metamorphic rocks of the Qinling Group in two magmatic stages: (i) the Early Silurian Huichizi granite that was derived from a low degree of partial melting of thickened lower basaltic crust combined with mantle-derived materials following the subduction of the Shangdan Ocean; and (ii) the Late Silurian–Early Devonian Damaogou granite and associated pegmatites derived from the same source but emplaced in a late tectonic post-collisional extension environment. In the Guangshigou deposit, the U mineralization mainly occurs as uraninite disseminated in U-rich granitic biotite pegmatites, which formed by assimilation-fractional crystallization magmatic processes. Petrographic observations showed evidence for coeval crystallization of uraninite and other rock-forming minerals of the host pegmatite including quartz, feldspar, biotite, zircon, monazite, apatite, and xenotime. In addition, the low U/Th ratios (~19) and Th, REE, and Y enrichments characterized a magmatic origin for uraninite, which was likely derived from fractionated high-K calc-alkaline pegmatitic magma that experienced various degrees of crustal material contamination. In situ U-Pb isotopic dating performed by Secondary-Ion Mass Spectrometry (SIMS) on uraninite from the Guangshigou deposit yielded a crystallization age of 412 ± 3 Ma, which is concomitant (within errors) with the emplacement age of the host pegmatite (415 ± 2 Ma) and constrained the U ore genesis to the Early Devonian, which corresponds to the late Caledonian post-collisional extension in the North Qinling area. Uraninite then experienced various degrees of metamictization and/or post-Caledonian hydrothermal alteration characterized by an alteration rim associated with coffinite, chlorite and limonite. Finally, the characteristics of the pegmatite-related Guangshigou deposit exhibiting Th-rich uraninite which was the product of assimilation-fractional crystallization of pegmatitic magma defined a model significantly different than the one established for the world-class Rössing deposit characterized by Th-poor uraninite hosted in alaskite dykes formed by low degree of partial melting of U-rich metasediments.https://www.mdpi.com/2075-163X/11/4/402late CaledonianuraniniteSIMSGuangshigouuranium mineralizationNorth Qinling |