"After 18 months, the rig hands had reached 30,067 feet, just 2,000 feet from the target depth. And that is where Exxon halted. After spending an estimated $180 million, the company abandoned the field."

"Exxon won't discuss what happened at Blackbeard, except to say the pressure rose too high."

"Because of a quirk of such deep geology, the pressure underneath Blackbeard would drop within a few more feet of drilling, and thus become less perilous."

They should have read those articles I posted in 2007 about pressure-reversal :)