ROCKS

ROCKS, natural aggregates of minerals of a certain composition, forming independent geological bodies of Earth’s crust. By origin, they are divided into sedimentary (formed on Earth’s surface as a result of sedimentation and subsequent transformation of sea and continental sediments), magmatic [formed by solidifying magma in the bowels of the crust (plutonic or intrusive, – gabbro, granite, diorite, etc.) and on its surface] and metamorphic (formed due to the transformation of sedimentary and magmatic rocks under the influence of temperature and pressure deep in Earth’s crust). The platform and foothill parts of Bashkortostan, including the zone of the Pre Urals foreland basin, are built with sedimentary R. The Ural folded region, with the exception of its eastern part — Magnitogorsk Megasynclinorium, is built with predominantly sedimentary and to a lesser extent with magmatic rocks that experienced different degree of metamorphism and strong tectonic deformations. The latter is composed of effusive and sedimentary R., formed in the conditions of oceanic bottom, underwent subsequent folding and rupture dislocations and transformed in the conditions of greenstone metamorphism, broken by intrusive rocks.