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Sm-Nd, Rb-Sr, K-Ar and Re-Os isotopic constraints on the origin of PGE mineralization in the Konder massif, Khabarov region, Russia.
Published in Adam Piestrzyński, Mineral Deposits at the Beginning of the 21st Century, 2001
Y.D. Pushkarev, A.I. Kostoyanov, M.P. Orlova, E.S. Bogomolov, V.F. Guseva
The K-Ar ages, 132±8 Ma (biotite from pyroxenite) and 115±6 Ma (biotite from gabbro-pegmatite) are in accordance with Rb-Sr and Sm-Nd ages. Amphibole in hornblendite contains excessive 40Ar in a form of three-dimensional gas inclusions; due to this its K-Ar age (171±9 Ma) is higher than the real one. Therefore, amphibole was powdered, in order to release the 40Ar of these inclusions, and the powdered sample gave a K-Ar age of 151±8Ma, which is considered close to the real time of crystallization.
Genetic and ore-forming ages of the Fe–P–(Ti) oxide deposits associated with mafic–ultramafic–carbonatite complexes in the Kuluketage block, NW China
Published in Australian Journal of Earth Sciences, 2019
W. Chen, X. B. Lü, X. F. Cao, Q. Yuan, X. D. Wang
The pyroxenite phase is grey to grey-green in colour and consists of diopside (70–95 vol%), minor biotite, hornblende, magnetite, and apatite (Figure 7c-1,c-2). The biotite pyroxenite is grey in colour, and it is made up of biotite (70–85 vol%), diopside (15–20 vol%), minor magnetite, and apatite (Figure 7f-1,f-2). The hornblendite is grey-green in colour and is composed of hornblende (60–80 vol%), plagioclase (10–15 vol%), minor diopside, biotite, magnetite, and apatite (Figure 7a-1,a-2). The pink-white diorite consists of 50–60 vol% plagioclase, 10–15 vol% hornblende, 10–15 vol% biotite, minor diopside, magnetite, and apatite (Figure 7d-1, d-2). The pink-yellow monzogranite is composed of plagioclase (30–40 vol%), K-feldspar (20–30 vol%), quartz (10–15 vol%), minor biotite, hornblende, magnetite, and apatite (Figure 7b-1, b-2).