which includes the carbon emitted from combustion of the final product. [ 65 ] [ 66 ] Chuck Masters of the USGS estimates that, "Taken together, these resource occurrences, in the Western Hemisphere , are approximately equal to the Identified Reserves of conventional crude oil accredited to the Middle East." [ 72 ] Authorities familiar with the resources believe that the world's ultimate reserves of unconventional oil are several times as large as those of conventional oil and will be highly profitable for companies as a result of higher prices in the 21st century. [ 73 ] In October 2009, the USGS updated the Orinoco tar sands (Venezuela) recoverable "mean value" to 513 billion barrels (8.16 × 10 10 m 3 ), with a 90% chance of being within the range of 380-652 billion barrels (103.7 × 10 ^ 9 m 3 ), making this area "one of the world's largest recoverable oil accumulations". [ 74 ] Despite the large quantities of oil available in non-conventional sources, Matthew Simmons argued in 2005 that limitations on production prevent them from becoming an effective substitute for conventional crude oil. Simmons stated "these are high energy intensity projects that can never reach high volumes" to offset significant losses from other sources. [ 76 ] Another study claims that even under highly optimistic assumptions, "Canada's oil sands will not prevent peak oil," although production could reach 5,000,000 bbl/d (790,000 m 3 /d) by 2030 in a "crash program" development effort. [ 77 ] Moreover,