Lenticular reservoir sands, when studied in the light of their depositional environment, shed considerable light on their nature and distribution. Lower Pennsylvanian sands of the Oklahoma part of the McAlester-Arkansas Valley Coal basin are lenticular in character and occur on the fringing shelf areas of the embayment. Successive epochs of Early Pennsylvanian subsidence are characterized by the deposition of lenticular sands, principally of the deltaic type. Examples of deltaic lenticular sands are known to occur in the Booch, Bartlesville, and Prue sandstone formations. Depositional environments are reconstructed by means of drawing isopachs of the genetic stratigraphic intervals in which these sands occur. Such maps serve to negate any significance of present structure and reveal the (1) shoreline trends, (2) distribution of shelf areas, and (3) the principal direction from which the sediments were derived. Additional maps of the individual reservoir sands, such as structure, thickness, isopotential, and reciprocal isopachs, reveal the nature of the lenticular sands within the genetic units. A knowledge of the origin and distribution of such sand bodies, both ancient and recent, is considered essential to the discovery of new stratigraphic traps of this type and to their exploitation once they are discovered.

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