Upper Devonian sandstone microfractures (Kodinka Fault Block, Alapayevsk-Techa Zone, Middle Urals Eastern slope)

Abstract

Microscale fractures of Upper Frasnian Kodinka Formation and Famennian Ust`kodinka Formation sandstones are considered in this work. It`s found that genesis of the microfractures and their mineral filling is associated with late and uplift diagenetic alterations. Moreover we suppose that illite/smectite transformation fluids were the main source of silica. For the carbonate mineral filling it was both noted fluids and other formations fluids. Example of the last-named may be underlyindg carbonate formation and Kodinka fault block adjacent carboniferous formations.