Oil Reserves In Alberta

Abstract

Abstract Introduction IT IS OF CONSIDERABLE INTEREST TO KNOW the total amount of conventional crude oil which can be recovered in Alberta. The Energy Resources Conservation Board has estimatedl J1 this quantity at 20 billion barrels; it also estimated the annual increase of proved reserves at 450 million barrels. These estimates were obtained by considering the curve of proved reserves of the province over the past 25 years and extrapolating linearly. This is similar to the methods applied to the crude oil reserves of the U.S. by Hubbert(1) and Moore (see Lovejoy and Homan(2)) though the curves fitted by Hubbert and Moore were somewhat more complicated. Such curve-fittings have their disadvantages. There may be many reasons why a trend which has been present for many years suddenly changes. It is much better to formulate a relationship between the reserves and some other variables which explains the development of these reserves, To estimate such a relationship and to use it for projections is the main purpose of this article. The increase of the initial recoverable proved reserves (that is all oil known to be recoverable plus all oil produced so far) in any year consists of reserves (that is all oil known to be recoverable plus exploratory wells and additions to and revisions of reserves of oil pools found previously; these additions and revisions are called the appreciation of reserves. Let us indicate the total proved reserves of the province in year t by Pt and proved reserves in year t of an oil pool discovered in year τ by P (τ) it is obvious that P (τ)t = 0 for t < τ. We have then (Equation Available In Full Paper) P(t), are the proved reserves of pools discovered in year t and P(t0)?.P(t-1), are the proved reserves of pools discovered in previous years to, ..., t-l, where to is the year in which the first reserves were discovered. The appreciation of oil reserves over the years is quite erratic. Nevertheless, it is possible to estimatethe average appreciation of reserves as a function of the years since discovery. The Energy Resources Conservation Board has used(3) the formula (Equation Available In Full Paper) where r(t) is the average multiple of the proved reserve in the year of discovery after t years, and a and b are estimated from curve 1 in Figure 1, which gives the averages resulting from the data available. Curve 2 gives the curve fitted in to curve 1, taking into account some other information which* results in the values a = 8.495, b*= 4.4505 or b = 0.7988. Because the fit of curve 2 is not very good, the author of this article used a nonlinear least-squares procedure to fit (1,2) to curve 1, which resulted in a = 8.7711 and b = 0.88381.