Offshore drilling moves to the deep end
Plumbing the ocean's depths for oil has long since outpaced drilling at shallower depths
The proportion of deepwater drilling in the Gulf of Mexico first began to outpace drilling at shallower depths in the early 1980s, figures from the U.S. Department of the Interior Minerals Management Service show. The gap grew steadily until the late-1990s, when production from deepwater plays rose dramatically. The sudden increase in deepwater activity lends credence to the argument that oil is increasingly harder and more expensive to access.
Source: U.S Department of the Interior Minerals Management Service