Great point. And, opec countries, plus some others, are not open to commercial development where anybody can buy or lease land anywhere and everywhere. The US is fully explored because there were never any limits on production (except texas), so constraints were entirely economic.

OTOH, consider that in 1999 SA chose to devlop Shaybah, located very deep in the empty quarter, where production costs are much higher, and anyway development required expensive, horizontal multilateral wells. Presumably, this was at that time their lowest cost option.

BTW, their doubling of rigs may be necessary to maintain production because they are now resorting to horizontal wells, which take longer to drill.

The Lower 48 is a fascinating HL case.  Khebab took only the Lower 48 production through 1970 to  generate a predicted post-1970 production profile (through 2004).  

The post-1970 cumulative Lower 48 production was 99% of what the HL model predicted that it would be.  What is interesting is that unrestrained drilling for smaller fields had no discernible effect.  

Is it possible that the Saudis have been pre-occupied with size?  Shaybah afterall was the biggest field on their books and a major exploration success.  At some point they must get around to developing 100,000 bopd fields using 50 production wells and 20 injectors.  I'm sure 2000 bopd doesn't sound great in Saudi.  Are there any on-shore wells in Texas that still produce 2000 bopd?
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