The Ohio driller's "Newburg sand" or Newburg zone lies in a stratigraphic position approximately equivalent to part of the Guelph Formation of the Lockport Group (i.e., at the top of the Lockport and just below the Salina A Unit of the Cayugan). The Newburg is characterized by a higher overall porosity than the rest of the Lockport. The porous dolomite extends downward as much as 80 to 100 ft (25 to 30 m) below the top of the Lockport. More than one interval may be porous. Stratigraphically, the base of the Newburg zone parallels the top of the Lockport regardless of whether the Lockport is thick or thin. The thickening of the Lockport occurs locally, especially where there has been a thickening of the lower unit of that group, the Gasport Formation. The thick Newburg zon in the upper Lockport tends to overlie thick Gasport and may reflect reef or reefoid buildup in the Guelph Formation. Mapping of the Lockport surface shows that local structure is caused by the thickening. The small local structures can be detected several hundred feet up-section because of the draping effect of overlying beds on the more rigid Lockport dolomites. Structural mapping of the top of the Lockport or of the top of the Devonian "Big Lime" (Columbus Limestone) may reveal areas of potentially productive thickening of the Newburg zone.

The Newburg usually contains salt water. Accumulation of commercial gas is controlled both by local structural features and by changes in the relative percent porosity in the Newburg and consequent change in the total porosity feet. Examination of production records from four Newburg gas pools in Summit County, Ohio, shows that the largest and longest yields come from wells located high on structure.

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