Marathon has begun drilling the exploration well 35/30 in the Porcupine Basin, 112 kilometres off the Kerry Coast.

This is the first well to be drilled in the 35/30 block licence area and the cost is likely to exceed £15 million. Marathon, which was awarded the block area licence in 1995, has been actively involved in the search for oil and gas in Irish waters since 1970.

Drilling will continue for three months using the semi-submersible drilling unit "Jack Bates", which can operate in water depths in excess of 6,000 feet (1,830 metres).

The Marathon operated consortium consists of Marathon International (33.33 per cent), Philips Petroleum Company (33.33 per cent), Occidental of Ireland (23.33 per cent) and Global Petroleum (10.00 per cent).