This study is focused on the gas-producing marine portion of the basal Foremost Formation. The producing sandstones of the Strathmore Belly River gas pool are interpreted as a regressive (prograding) shoreface succession. A rapid drop in base level shifted the shoreline basinward creating incised fluvio-deltaic channels and valleys. Gas production is from upper shoreface and channel sandstones with the highest productivity being obtained from the coarser grained channel sandstones, which exhibit superior porosities and permeabilities. Hydrogeologic analysis has defined a regional gas and water gradient common to the marine sandstones of the basal Foremost Formation. The virgin gas/water contact elevation is approximately +62m subsea. Sandstones with >18% porosity elevated above +62m subsea can be interpreted as gas pay. The regional communication between the basal marine sands is supported by both hydrogeologic analysis and production data.