Mineralogical–Geochemical Types and 190Pt–4He Age of Ferroan Platinum of Placers of the Anabar River Basin, Northeastern Part of the Siberian Platform


Cite item

Full Text

Open Access Open Access
Restricted Access Access granted
Restricted Access Subscription Access

Abstract

Typical features of platinum group minerals (PGMs) and the results of 190Pt–4He dating of the Fe–Pt solid solutions are presented for complex gold–platinum–diamond placers with unidentified sources of the Anabar River basin. For the first time, the 190Pt–4He isotopic system is used for determination of the possible age of the primary source of a PGM placer from the example of ferroan platinum with a disordered structure along with isoferroan platinum. The PGMs of these placers mostly include ferroan platinum and isoferroan platinum and rare Ru–Ir–Os alloys. The calculated bulk composition of the silicate inclusion of Ir platinum corresponds to the rocks of the ijolite–melteigite series. The 190Pt–4He age of the Fe–Pt solid solution grains is 261 ± 13 Ma. Thus, our data indicate the relation between placer PGMs of the Anabar River basin and Permian–Triassic complexes of alkaline–ultramafic rocks.

About the authors

A. V. Okrugin

Diamond and Precious Metal Geology Institute,
Siberian Branch, Russian Academy of Sciences

Author for correspondence.
Email: a.v.okrugin@diamond.ysn.ru
Russian Federation, Yakutsk, 677980

O. V. Yakubovich

Institute of Precambrian Geology and Geochronology, Russian Academy of Sciences; St. Petersburg State University

Email: a.v.okrugin@diamond.ysn.ru
Russian Federation, St. Petersburg, 199034; St. Petersburg, 199034

A. M. Gedz

Institute of Precambrian Geology and Geochronology, Russian Academy of Sciences; St. Petersburg State University

Email: a.v.okrugin@diamond.ysn.ru
Russian Federation, St. Petersburg, 199034; St. Petersburg, 199034

A. L. Zemnukhov

OAO Almazy Anabara

Email: a.v.okrugin@diamond.ysn.ru
Russian Federation, Yakutsk, 677000

P. O. Ivanov

Diamond and Precious Metal Geology Institute,
Siberian Branch, Russian Academy of Sciences

Email: a.v.okrugin@diamond.ysn.ru
Russian Federation, Yakutsk, 677980

Supplementary files

Supplementary Files
Action
1. JATS XML

Copyright (c) 2019 Pleiades Publishing, Ltd.