Geochemical features and geodynamic setting of formation of the Lukinda dunite–troctolite–gabbro massif (southeastern framing of the Siberian Platform)

Abstract

The Lukinda dunite–troctolite–gabbro massif in the Selenga–Stanovoy superterrane on the southeastern framing of the Siberian Platform was earlier considered Precambrian. The performed 40Ar/39Ar dating of the massif plagioclase yielded an Early Permian age (285 ± 7.5 Ma). The main specific petrochemical features of the intrusion rocks during their crystallization differentiation are an increase in SiO2 and CaO contents and a decrease in FeOtot content, with TiO2 content remaining low and showing minor variations. A specific geochemical feature of the Lukinda massif ultrabasite–basites is a slight domination of LREE over HREE, with (La/Yb)N = 1.0–8.2. The depletion of the massif rocks in LILE (except for Sr and Ba), REE, and HFSE suggests that the massif formed on an active continental margin.

Deformation patterns and timing of the thrust‐nappe structures in the Mohe Formation in Mohe Basin, Northeast China: Implication of the closure timing of Mongol–Okhotsk Ocean

“…These age populations of pre‐Mesozoic are utterly consistent with those of granitoids and metasedimentary rocks in Northeast China including Erguna Block (e.g., Wu, ; Wu et al, , Wu et al, , Wu, Chen, Chen, & Zeng, ; Ge, Wu, Zhou, & Abdel Rahman, , Ge, Sui, Zhang, Xu, & Cheng, ; Gou et al, ; Li et al, ; Qin et al, ; She et al, ; Tang et al, , ; Wu et al, ; Xu, Charvet, Chen, Zhao, & Shi, ; Zhou et al, ; Han et al, ) and Siberian Block (e.g., Buchko, Sorokin, Ponomarchuk, & Izokh, ; Dobretsov, Buslov, & Vernikovsky, ; Gladkochub et al, , ; Kozakov et al, ; Kuzmichev, Bibikova, & Zhuravlev, ; Tomurtogoo et al, ; Yarmolyuk et al, ) and suggest that the Northeast China and Erguna Block to the south of the Mohe Basin and Siberian Block to the north were sources for the foreland basin's sediments throughout the deposition of the Mohe Formation (He et al, , ; Hou et al, ; Zhang et al, ).…”

The Lukindinskii dunite-troktolite-gabbro massif of the Upper Amur Region: New geological, geochronological, and geochemical data

“…It has an ellipsoid form of sublatitudinal trending with a length of up to 16 km and a width up to 6 km. In accordance with the tradi tional view [3,4], the dunite-peridotite-troctoliteanorthosite association of rocks of the lower laminated series and the pyroxenite-gabbro-gabbronorite asso ciation of the upper laminated series form the massif.…”

“…The most popular in the literature is the petrotype of the complex-the Lukindinskii massif. It has attracted great attention [2][3][4].…”

“…-2-xenoblocks of dunite-melan-gabbroids: dunites (1); olivine melannorites (2); 3-5-lower laminated series: olivine containing anorthosites (3); leucotroctolites(3,4); norites (5); 6-upper laminated series: hornblende gabbro. nd-The element was not determined.…”

Localization of PGE mineralization in southeastern Russia

“…Geochronological studies performed in the recent decade have proved the multistage evolution of gabbro-anorthosite and mafic-ultramafic magmatism in southeastern Russia. Formation of Neoarchean, Paleoproterozoic, Late Riphean, Permo-Triassic, and Late Mesozoic intrusions was related to the activity of plumes of several generations (Buchko, 2010;Buchko et al, 2012;Dobretsov et al, 2010;Larin et al, 2006). The complex and multistage development of magmatic and associated metasomatic processes determining the productivity of PGE mineralization in the forming layered plutons was confirmed by Gongal'skii (2012), Konnikova et al (1999), andTolstykh et al (2008).…”