Ministerial Decree No. 260 validating classification of gas fields and oilfields.

This Ministerial Decree establishes common principles of calculation, evaluation and the state registration of gas fields and oilfields, industrial development thereof. It shall be compulsory for all subsoil managers carrying out exploration, prospecting and mining of gas fields and oilfields. Reserves of gas and oil shall be calculated, registered and recorded in the national balance of minerals. Evaluation and registration of reserves shall be carried out separately for each gas field and oil field. In case of extraction in gas fields and oil fields of groundwater its composition, temperature and other indices must be determined for the purpose of its possible utilization for heat-and-power engineering and balneal purposes. Reserves of gas and oil shall be classified by degree of exploration and validity into proven, preliminarily evaluated, perspective and projected reserves.