Inčukalns gas storage facility utilising Ordovician dome

The Inčukalns Underground Gas Storage facility is situated in the central part of Latvia (Riga District). The structure is of great practical importance, because it has stored natural gas since 1968. 200 wells reaching the reservoir were drilled in the territory of the facility and extensive seismic prospecting was carried out there. The reservoir consists of porous and permeable sandstone which is overlaid by a clay. According to calculations made in 1968, the total volume of the Inčukalns underground gas storage was evaluated at 5.7 billion m3. At the State Geology Fund are over fifteen geological, hydrogeological and seismic research review materials from the period 1960 to 1994.