Research output: Contribution to journal › Article › peer-review
Uranium-Pb zircon ages, whole-rock and zircon mineral geochemistry as indicators for magmatic fertility and porphyry Cu-Mo-Au mineralization at the Bystrinsky and Shakhtama deposits, Eastern Transbaikalia, Russia. / Nevolko, Peter A.; Svetlitskaya, Tatyana V.; Savichev, Andrey A. et al.
In: Ore Geology Reviews, Vol. 139, 104532, 12.2021.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Uranium-Pb zircon ages, whole-rock and zircon mineral geochemistry as indicators for magmatic fertility and porphyry Cu-Mo-Au mineralization at the Bystrinsky and Shakhtama deposits, Eastern Transbaikalia, Russia
AU - Nevolko, Peter A.
AU - Svetlitskaya, Tatyana V.
AU - Savichev, Andrey A.
AU - Vesnin, Vladislav S.
AU - Fominykh, Pavel A.
N1 - Funding Information: The authors sincerely thank Associate Editor of the journal Ore Geology Reviews Dr. Daniel Muller and the anonymous reviewers for their constructive review, editorial handling and helpful comments all of which greatly improved this manuscript. This study is done on state assignment of IGM SB RAS. Publisher Copyright: © 2021 The Authors
PY - 2021/12
Y1 - 2021/12
N2 - The Bystrinsky Cu-Au-Fe porphyry-skarn and Shakhtama Mo ± Cu porphyry deposits in Eastern Transbaikalia, Russia, are spatially associated with a series of fertile and non-fertile calc-alkaline to shoshonitic I-type granitoid suites, ranging in composition from porphyritic monzonites and granodiorites to granodiorite- and granite-porphyries. The obtained zircon U-Pb geochronological data reveal a narrow age interval of 1–3 Ma for the igneous suites within the Bystrinsky deposit (ca. 159–163 Ma), which is consistent with the short-magmatic activity at the Shakhtama deposit (ca. 164–161 Ma). Within both deposits, the fertile magmatic pulses comprise hybrid, high-silica and high- to moderate-magnesian, oxidized melts with relatively high magmatic water contents. These weakly fractionated melts represent the late-stage magmatic pulses of the Shakhtama Complex. By contrast, the barren magmatic pulses comprise a wide range of compositions, generally with lower magmatic water contents and oxidation states as well as significant plagioclase fractionation and crustal contamination. The Shakhtama Mo-related porphyries are more evolved when compared to the Bystrinsky Cu-Au intrusions reflecting significant crustal assimilation in addition to amphibole-plagioclase fractionation. Both whole-rock geochemistry and zircon mineral chemistry from the Bystrinsky and Shakhtama deposits may be used as fertility indicators in target generation and regional mineral exploration in Eastern Transbaikalia. More specifically, we propose critical thresholds of whole-rock Sr/Y and 10,000*(Eu/Eu*)/Y ratios of > 65 and > 850, respectively, and zircon mineral Eu/Eu*, Ce/Ce* and Yb/Dy ratios of > 0.4, >750 and > 4, respectively. Additionally, we propose an alternative method to calculating the Ce anomalies of zircons using MS Excel-based software which is provided in the Supplementary data of this paper.
AB - The Bystrinsky Cu-Au-Fe porphyry-skarn and Shakhtama Mo ± Cu porphyry deposits in Eastern Transbaikalia, Russia, are spatially associated with a series of fertile and non-fertile calc-alkaline to shoshonitic I-type granitoid suites, ranging in composition from porphyritic monzonites and granodiorites to granodiorite- and granite-porphyries. The obtained zircon U-Pb geochronological data reveal a narrow age interval of 1–3 Ma for the igneous suites within the Bystrinsky deposit (ca. 159–163 Ma), which is consistent with the short-magmatic activity at the Shakhtama deposit (ca. 164–161 Ma). Within both deposits, the fertile magmatic pulses comprise hybrid, high-silica and high- to moderate-magnesian, oxidized melts with relatively high magmatic water contents. These weakly fractionated melts represent the late-stage magmatic pulses of the Shakhtama Complex. By contrast, the barren magmatic pulses comprise a wide range of compositions, generally with lower magmatic water contents and oxidation states as well as significant plagioclase fractionation and crustal contamination. The Shakhtama Mo-related porphyries are more evolved when compared to the Bystrinsky Cu-Au intrusions reflecting significant crustal assimilation in addition to amphibole-plagioclase fractionation. Both whole-rock geochemistry and zircon mineral chemistry from the Bystrinsky and Shakhtama deposits may be used as fertility indicators in target generation and regional mineral exploration in Eastern Transbaikalia. More specifically, we propose critical thresholds of whole-rock Sr/Y and 10,000*(Eu/Eu*)/Y ratios of > 65 and > 850, respectively, and zircon mineral Eu/Eu*, Ce/Ce* and Yb/Dy ratios of > 0.4, >750 and > 4, respectively. Additionally, we propose an alternative method to calculating the Ce anomalies of zircons using MS Excel-based software which is provided in the Supplementary data of this paper.
KW - Bystrinsky
KW - Eastern Transbaikalia
KW - Fertility indicators
KW - Porphyry deposits
KW - Shakhtama
KW - U-Pb age
KW - Whole-rock geochemistry
KW - Zircon geochemistry
UR - http://www.scopus.com/inward/record.url?scp=85118159495&partnerID=8YFLogxK
U2 - 10.1016/j.oregeorev.2021.104532
DO - 10.1016/j.oregeorev.2021.104532
M3 - Article
AN - SCOPUS:85118159495
VL - 139
JO - Ore Geology Reviews
JF - Ore Geology Reviews
SN - 0169-1368
M1 - 104532
ER -
ID: 34554021