Scholar: Unconventional gas reserves âenormousâ
For every Mcf of gas produced from conventional basins around the
world, nine times that amount of recoverable unconventional gas exists
in the same basin, according to the head of the petroleum engineering
department at Texas A&M University.
Stephen Holditch told Platts on the sidelines of the Offshore
Technology Conference in Houston late Monday that the 1:9 ratio is
based on a study of eight North American basins.
âWeâve studied publicly available data on how much oil and gas has
been produced in different basins and how much is still in these basins
in terms of proved, probable and possible reserves,â he said. âIt falls out that 10%
of the oil and gas is in conventional reservoirs and 90% is in unconventional
ones,â including coalbed methane, shale gas and tight-sands gas.
âWe feel that this 90-10 split is part of how natural gas resources are distributed,
and it will more or less hold true for every natural gas basin in the world,â
Holditch said.
His team of researchers examined only those reserves classified as technically
recoverable. âWe know where it is and we have the technology to recover it,
but we canât book it as reserves because we either havenât drilled the wells or
thereâs no pipeline there, or the gas price isnât high enough to make it economic,â
he added.
Unconventional gas reserves such as those found in the Bossier Sands in East
Texas and the Haynesville, Barnett, Woodford, Haynesville and Marcellus shales
âarenât unique to North America,â Holditch maintained. âSouth America, the
Middle East, Russia, the North Sea or wherever, if you can go into these basins
and estimate the amount of conventional oil and gas thatâs going to be recovered,
multiply that by nine and thatâs how much unconventional gas can be
recovered.â
Holditchâs hypothesis contradicts popular theories â such as the peak oil theory
â that the world is running out of hydrocarbons. âThe peak oil theory is
based on production from conventional oil fields,â he said. âWhat Iâm saying is
that peak oil theory is only the top of that resource triangle.â
According to Holditch, âthereâs an enormous amount of unconventional oil
and gasâ around the world, including heavy oil in Canada, Venezuela and
Indonesia, as well as the shale gas being developed in the US.
âThere are a lot of tight gas reservoirs in the Middle East. Theyâre just now
waking up to what they really have,â he said. âThe other basins in the Middle
East and Russia have never tested their source rocks and when they do, theyâre
going to find enormous amounts of oil and gas.â â Jim Magill
From Platts Gas Daily, May 6, 2009 issue