Many oil and gas companies use mat-supported jackup for exceptionally soft unconsolidated sea bed conditions as in tidal deltas. With this type of rig, they replaced the spud cans with a large mat, often covering a sea bed area more significant than the vessel’s hull.
[pdf] The Deepwater Horizon oil spill began on April 20, 2010, when an explosion damaged the Deepwater Horizon oil rig. The rig's sinking on April 22 began the discharge of oil into the Gulf of Mexico.. On April 20, 2010, the oil drilling rig Deepwater Horizon, operating in the Macondo Prospect in the Gulf of America, exploded and sank resulting in the death of 11 workers on the Deepwater Horizon and the largest spill of oil in the history of marine oil drilling operations.
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