 <unk> exploration is ongoing following the first major find at the <unk> Head gas field off Cork in the mid @-@ 1970s . In 1999 , economically significant finds of natural gas were made in the <unk> Gas Field off the County Mayo coast . This has increased activity off the west coast in parallel with the " West of Shetland " step @-@ out development from the North Sea <unk> province . The <unk> oil field , estimated to contain over 28 million barrels ( 4 @,@ 500 @,@ 000 m3 ) of oil , is another recent discovery . 
