Research output: Contribution to journal › Article › peer-review
190Pt–4He Dating of Placer-Forming Minerals of Platinum from the Chad Alkaline–Ultramafic Massif : New Evidence of the Polycyclic Nature of Ore Formation. / Mochalov, A. G.; Yakubovich, O. V.; Bortnikov, N. S.
In: Doklady Earth Sciences, Vol. 504, No. 1, 01.05.2022, p. 240-247.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - 190Pt–4He Dating of Placer-Forming Minerals of Platinum from the Chad Alkaline–Ultramafic Massif
T2 - New Evidence of the Polycyclic Nature of Ore Formation
AU - Mochalov, A. G.
AU - Yakubovich, O. V.
AU - Bortnikov, N. S.
N1 - Publisher Copyright: © 2022, Pleiades Publishing, Ltd.
PY - 2022/5/1
Y1 - 2022/5/1
N2 - Abstract: The results of 190Pt–4He dating of placer-forming platinum-group minerals (PPMs) from the placer deposits of Mokhovoi Creek, its tributaries, and eluvial and proluvial deposits of the peneplain surface of dunites of the Chad alkaline-ultramafic massif (Aldan Shield, Ayan-Maya district of Khabarovsk krai) are presented. 190Pt and 4He were measured in 27 samples. The statistical processing of the mineralogical and geochemical data allows us to separate three 190Pt–4He age isochrones (Ma): 123 ± 6; 113 ± 6; and 107 ± 6, which is in good agreement with the geological observations and the mineralogy of the platinum group elements (PGEs) of the Chad massif. The range of 190Pt–4He age isochrones indicates that platinum-metal ore formation occurred over 16 Myr. The geological and mineralogical data and the 190Pt–4He isochrones of different ages allow us to conclude that the platinum-metal ore formation in the Chad massif was polycyclic during the Early Cretaceous. A comparison of the 190Pt–4He ages of the PPMs of the Chad and Kondyor alkaline-ultramafic massifs indicates that there are temporal features between the platinum ore formation and the formation of these plutons during the Mesozoic tectonic–magmatic activation of the Aldan Shield.
AB - Abstract: The results of 190Pt–4He dating of placer-forming platinum-group minerals (PPMs) from the placer deposits of Mokhovoi Creek, its tributaries, and eluvial and proluvial deposits of the peneplain surface of dunites of the Chad alkaline-ultramafic massif (Aldan Shield, Ayan-Maya district of Khabarovsk krai) are presented. 190Pt and 4He were measured in 27 samples. The statistical processing of the mineralogical and geochemical data allows us to separate three 190Pt–4He age isochrones (Ma): 123 ± 6; 113 ± 6; and 107 ± 6, which is in good agreement with the geological observations and the mineralogy of the platinum group elements (PGEs) of the Chad massif. The range of 190Pt–4He age isochrones indicates that platinum-metal ore formation occurred over 16 Myr. The geological and mineralogical data and the 190Pt–4He isochrones of different ages allow us to conclude that the platinum-metal ore formation in the Chad massif was polycyclic during the Early Cretaceous. A comparison of the 190Pt–4He ages of the PPMs of the Chad and Kondyor alkaline-ultramafic massifs indicates that there are temporal features between the platinum ore formation and the formation of these plutons during the Mesozoic tectonic–magmatic activation of the Aldan Shield.
KW - Pt–He dating
KW - Aldan Shield
KW - alkaline rocks
KW - Chad massif
KW - genesis
KW - mineralogical–geochemical types
KW - platinum group minerals
KW - ultramafic rocks
KW - 190Pt–4He dating
UR - http://www.scopus.com/inward/record.url?scp=85131936091&partnerID=8YFLogxK
UR - https://www.mendeley.com/catalogue/f43c9fcf-7f36-392e-8e15-50b8833f3798/
U2 - 10.1134/s1028334x22050105
DO - 10.1134/s1028334x22050105
M3 - Article
AN - SCOPUS:85131936091
VL - 504
SP - 240
EP - 247
JO - Doklady Earth Sciences
JF - Doklady Earth Sciences
SN - 1028-334X
IS - 1
ER -
ID: 99063757