INFERRED RESERVES (RESERVE GROWTH)


     Inferred reserves (reserve growth) include those resources expected 
to be added to reserves as a consequence of extension of known fields,
through revisions of reserve estimates, and by additions of new poolsin 
discovered fields. Also included in this category are resources expected 
to be added to reserves through application of improved recovery techniques. 
This category thus includes both the "indicated reserves" and the "inferred 
reserves" described in earlier USGS assessment publications (e.g., Mast and 
others, 1989). Predictions of reserve growth refer to fields found before 
1992 (the date of most reserve data used in this report). The analysis of 
reserve growth in discrete conventional accumulations is based on the 
proprietary Oil and Gas Integrated Field File (OGIFF) of the Energy Information
Administration (EIA). Inferred reserves are shown in the stippled area of 
the middle third of the McKelvey box (fig. 4).