Re: Shell to begin construction of Prelude floating liquefied natural gas facility
I think rising worldwide demand for energy is a more important driver right now than scarcity of the resources themselves. Supplies are not meeting demand, so prices go up, but it's more about customers like China and India than dwindling oil and gas fields.
As far as natural gas goes, there are also issues with being allowed to build gas terminals onshore, and gas pipelines.
You are right that the easy stuff is mostly gone. At least in places we're allowed to get it out.