Uralian magmatism: an overview

U-Pb Silurian age for a gabbro of the Platinum-bearing belt of the Middle Urals (Russia): evidence for beginning of closure of the Uralian Ocean

“…Several independent lines of evidence concur with a Silurian age for the UPB. The schematic distribution of the Uralian magmatism in space and time given by Fershtater et al (1997), in particular for rocks of the dunite-clinopyroxenite -gabbro series, is in very good agreement with the Wenlock age of the Kumba massif. Those researchers indicated a Late Ordovician-Early Silurian age for rocks of the suture sector, east of the MUF, including the UPB.…”

“…It is located east of the MUF where the suture sector widens and is characterized by the abundance of zoned mafic-ultramafic complexes. These massifs are similar to Alaskan-type complexes (Irvine 1967) and show the typical association dunite-clinopyroxenite-gabbro (DCG units of Fershtater et al 1997). The UPB consists of a series of 13 rounded to elongated massifs forming a discontinuous but linear elongated zone, which crops out for a distance of about 900 km (Fig.…”

“…Existing models for the Palaeozoic tectonic development of the Uralides involve break-up of the EEC margin and initiation of the opening of the Uralian Ocean during Ordovician times, at c. 480-500 Ma (Zonenshain et al 1984;Fershtater et al 1997). The subsequent evolution of this oceanic domain is characterized by the building of several volcanic island arcs within or peripheral to the Uralian Ocean.…”

Platinum-Group Minerals and Other Accessory Phases in Chromite Deposits of the Alapaevsk Ophiolite, Central Urals, Russia

“…The mafic-ultramafic complexes can be grouped into three main types: (1) harzburgite-dunite-volcanic associations considered to be sections through the upper mantle-crust transition of Palaeozoic ophiolites; (2) concentrically zoned dunite-clinopyroxenite-gabbro intrusions derived from deep magmatic activity in island arc (Ural-Alaskan type) complexes and (3) lherzolite-harzburgite blocks representing weakly depleted mantle derived rocks that formed the floor during overthrusting of huge allochthonous or huge ophiolite massifs that were true oceanic crust [2][3][4][5][6].…”

The geology and genesis of the iron skarns of the Turgai belt, northwestern Kazakhstan

“…Magnitogorsk and Mali Kuibas deposits have been suggested to have formed from 342-337Ma, contemporaneous with the age of the Magnitogorsk intrusion (Fershtater, 1997;2007;Fig. 22).…”