Legs of Noble rig penetrate sea floor off Qatar

SAN FRANCISCO, May 12 (Reuters) - All three legs of an oil and gas drilling rig have penetrated the sea floor off the coast of Qatar, causing severe damage to the jackup and its legs, rig owner Noble Corp (NE.N) said.

The Noble David Tinsley experienced the "punch-through" while conducting preloading operations on May 8, according to a filing by Noble with U.S. financial regulators on Monday.

The rig was stable and no injuries or pollution had been reported, Noble said. A spokesman was not immediately available for further comment.

Noble said its insurance deductible was $25 million for such an event. Analysts had been expecting the company to earn a profit before exceptional items of $392 million in the second quarter, according to the average on Reuters Estimates.

Noble bought the jackup, which can drill to 25,000 feet (7,600 meters) in 300 feet of water, from A.P. Moller-Maersk (MAERSKb.CO) for more than $40 million in 2004. (Reporting by Braden Reddall; Editing by Andre Grenon)