Deformation-driven differentiation of granitic magma: the Stepninsk pluton of the Uralides, Russia

Magmatic differentiation in the calc-alkaline Khalkhab–Neshveh pluton, Central Iran

“…It seems that the initial 87 Srj 86 Sr increases with decreasing ages of piu tons, which might result from enrichment of the mantle beneath Central Iran during the contin uous subduction of Neotethyan Ocean beneath Iranian plate, or a switch in the source of intermediate (mostly gabbroic) rocks from mantle to lower crust. Many previous workers have shown that mineralogical and geochemical variations in magmatic suites from volcanic arcs can be produced by either magma mixing (e.g., Popov et al, 1999;Bea et al, 2005) or assimilation-fractional crystallization processes (DePaolo, 1981;Spera and Bohrson, 2001;Thompson et al, 2002;Kuritani et al, 2005). These hypotheses, however, may be limited by the isotope data.…”

LA ICP MS U–Pb ages of detrital zircons from Russia largest rivers: Implications for major granitoid events in Eurasia and global episodes of supercontinent formation

“…Geologically, the territory of Russia consists of two major Archean-Paleoproterozoic cratons of East Europe (East European Craton, EEC, or Baltica or Russian Platform in Russian literature) Milanovsky et al (1994), Puchkov (1997Puchkov ( , 2003, Glasmacher et al (2001), Khain and Nikishin (1998), Maystrenko et al (2003), Bea et al (2005), Shchipansky et al (2007), and Bogdanova et al (2008) Volga Vladimirov et al (1997Vladimirov et al ( , 1998Vladimirov et al ( , 1999, Rosen et al (1994), Fershtater et al (1997), Kruk et al (1999), Nozhkin et al (1999), Heinhorst et al (2000), Buslov et al (2001), Yarmolyuk et al (2001), Hong et al (2004), and Turkina et al (2007) (2001), Kovalenko et al (2004), Karsakov et al (2005), and Parfenov et al (2006) a Detailed description of geological features of river basins and their ages is given in Sections 2 and 4. and Siberia (Siberian Platform or Craton), large swathes of the Altaids/CAOB and a complex segment of Russian Far East consisting of geological units of different geodynamic origin (Zonenshain et al, 1990). The East European and Siberian Cratons are separated by the Ural Mountains and the world famous West Siberian Basin (WSB), which hosts rich oil and gas deposits (Fig.…”

“…The Early-Middle Paleozoic zircons could come from OrdovicianDevonian intermediate-acidic rocks that are widespread in the Urals, formed during subduction along the EEC margin prior to the main Baltica-Kazakhstan-Siberia collision events. The Late Paleozoic zircons-from Carboniferous-Permian granites that form the Main Granite Axis of the Urals, generated during the late stages of the Uralian orogeny (Puchkov, 1997;Bea et al, 2005).…”

Geology and mineralogy of Li mineralization in the Central Iberian Zone (Spain and Portugal)

“…The greater enrichment in Li, F, and probably also B and H 2 O, would notably reduce the viscosity of the most fractionated melts (Dingwell et al, 1996), and would also lower the liquidus temperature, enhancing the mobility of the melt. A filter-pressing mechanism (Propach, 1976), related to deformation that expels residual melts upwards, would result in a vertical chemical zonation in the magma chamber (Moyen et al, 2003;Bea et al, 2005). If melt were expelled along fractures, the highly fractionated melt in the upper part of the magma chamber would escape first.…”