The BP platform was scouring for ultra deep oil under 1600 meters of ocean water. From there they drilled another 6,000 meters into the crust of the earth, right at the edge of all current technological capacity.
It would seem that they hit a pocket of oil at such high pressure that it burst through all the safety valves all the way up to the drilling rig and then caused the rig to explode and sink.
The oil is now gushing out at a pressure of 2200 psi!
When the rig sank it flipped over and apparently landed close to the drill hole, 1600 meters under the ocean.
The Gulf Coast spill will have eclipsed the Exxon Valdez in terms of total gallons of oil before the weekend is over making it the largest oil spill in U.S. history according to calculations made by oceanographer Ian MacDonald after studying aerial Coast Guard photos taken earlier in the week.
MacDonald, a professor at Florida State University who counts “oil and gas development” among his areas of expertise, stopped short of comparing the Deepwater Horizon spill to that of the Alaskan oil tanker, but said Saturday, “The spill is growing. I’m comfortable saying that the size and extent of this slick is 10 million gallons.”
Given that just over a million gallons (3300 metric tons) of hot oil are leaking into the Gulf per day, according to MacDonald’s calculations, the spill will shortly top the Exxon Valdez’s estimated 11million gallon spill. It is almost certain to cost more than the Exxon spill, which cost $3.5 billion for cleanup and another $5 billion worth of lawsuits and other settlements.
Experts estimate it could take months to plug the leak and that things could be made worse by the approaching hurricane season.
Deepwater Horizon was an ultra-deepwater dynamic positioned semi-submersible oil rig built in 2001 at a cost of USD 350 Million. The purpose of this rig was to drill oil wells deep underwater, moving from location to location, as needed. Once the drilling was complete, pumping production was handled by other equipment.
Before the accident, Deepwater Horizon worked on BP’s Mississippi Canyon Block 252, referred to as the Macondo prospect. The rig was last located 50 miles off the southeast coast of Louisiana. In October 2009 BP extended the contract for Deepwater Horizon by three years, to begin in September 2010. The lease contract was worth US$544 million, a rate of $496,800 per day.