Speaking to Shana, Mohaddes said the studies would be completed in next four upcoming years. \"Given holding huge conventional oil reserves in the country, we don\'t need to invest on shale oil formations but Exploration Department should look at the future and plays an active role in finding new reserves,\" Mohaddes said. He added that some countries like the United States have huge reserves of shale gas but shale formations in Iran mainly contain oil. Referring to the ongoing exploration operations in West and South of the country, Mohaddes said that last year four oil and three gas layers were found in the country, including Somar, Khayyam, Medar, Farzad A and Delavaran. \"During the last Iranian calendar year to 19 March 2012, the company discovered 2.870 billion barrels of oil and 847 billion cubic meters of gas in total,\" the official noted. On drilling activities, the official said that last year more than 40 thousand meters of wells were drilled, adding that during the period 9 drilling rigs were operational in onshore sector while another one in offshore sector. He said the company conducted respectively 1.292 kilometers and 1.357 kilometers of two dimensional and three dimensional seismic operations last year. On exploratory activities in the offshore sector, the official said that last year the first well was drilled in Farzad A field, adding a contract has been signed with Petro Pars Company to drill the second well in the area. He expressed the hope a drilling rig to be set up in the Farzad A area to start operations as soon as possible. Mohaddes also noted that 40 exploratory targets and 14 blocks have been defined for investment.