courtesy Songa Offshore

Rig day rates have increased from $50,000 per day to $100,000/d since last year, making for a “monster” $425,000-a-day contract for Songa Offshore’s Songa Dee semi-submersible drill rig, the Norwegian-American drilling contractor said Thursday.

Marathon and Lundin will pay top dollar when the older rig starts two years of drilling for the oil companies in March 2009. “Sister” rig Songa Trym is available for hire early that same year.

Songa managers told analysts the two rigs are fine depsite getting on in years. They told of rig hulls that could last “100 years” with proper maintenance, although new and refurbished drilling equipment might need changing out at between five and 15 years.

In a illuminating slide show aimed at investors, Songa managers cited figures from DnB NOR Markets to show why the rig industry was still buoyant in Norway: 10 rigs in the Nordic country are contracted to the end of 2011, and 14 through to the end of 2010.

Songa, with cash in hand, is eying the purchase of another second-hand rig despite disappointment at the delayed deliveries of three recently off-the-yard rigs — the Venus, Saturn and Mercur. They were delivered late by 30 days, 2.5 months and 7.5 months in-line with some of the warnings issued by U.S. analysts two years ago over work managerment at some of the world’s shipyards.

Songa accumulated revenues of $108 million in first-half 2007, over $100 million better than in the year-ago period.