MonteQuest wrote:MattS wrote:
Hubberts concept was one of aggregation. He did not offer up a peak profile for only conventional oil in the US and compare that to one of unconventional oil...he offered up an aggregation of all oil production.
Including oil shale and tar sands? I never read such.
In 1956 Hubbert quantified the total fossil fuel "heating energy" of nearly everything in the United States. According to Hubbert in that work, the US contains something like 1/3 of the worlds total "heating energy" of fossil fuels, and a minority fraction of that was conventional crude oil and natural gas.
It appears, and this is an interpretation on my part, that he quantified in his bell shaped curve concept only that fraction of the resource pyramid which could be seen from 1956. He certainly counted everything, but I don't think he was explicit about what would compose the flow rates he envisioned in the future,
For example, many unconventional resources ( by modern definitions ) were already in production and being counted in the US total when he did his work. Fields like the Big Sandy and Devonian shale production in the Appalachian Basin, the unconventional oil of the Sprayberry trend, the unconventional oil of the Sanish ( Bakken ) in North Dakota.
The heavy oils of California alone were already being measured in the billions of barrels produced by 1956, and Colin Campbell certainly considers these types of resources as unconventional, and Hubbert did not withdraw them from his bell shaped curve in 1956.