If you want to get depressed about this, bet that the current American mess of monetary and fiscal policy will drive offshore some of the innovation we might have had.
Back an ice age or more sea levels were much lower than they are now and that silt has been deposited right across the area, sometimes above current coastlines, sometimes below them, close inshore and well offshore too.
Federal acreage onshore and offshore holds more than 2, 000 trillion cubic feet of natural gas (about 75 years worth of current domestic consumption) and 229 billion barrels of oil (about 50 years worth).