Changes

file:BasinCenteredGasFig11.jpg|{{figure number|9}}Generalized cross section CC' showing normally pressured, underpressured, and overpressured parts of the Clinton-Medina-Tuscarora interval (modified from Ryder and Zagorski<ref name=Ryderandzagorski_2003 />). The underpressured and overpressured areas of the Clinton-Medina-Tuscarora represent the indirect BCGA part of the interval where gas and minor amounts of water are produced, and the normally pressured area represents the conventional part of the interval where oil, gas, and water are produced. The hybrid, underpressured area represents transition from oil, gas, and water production in eastern Ohio to gas and minor water production in the BCGA.

file:BasinCenteredGasFig11.jpg|{{figure number|9}}Generalized cross section CC' showing normally pressured, underpressured, and overpressured parts of the Clinton-Medina-Tuscarora interval (modified from Ryder and Zagorski<ref name=Ryderandzagorski_2003 />). The underpressured and overpressured areas of the Clinton-Medina-Tuscarora represent the indirect BCGA part of the interval where gas and minor amounts of water are produced, and the normally pressured area represents the conventional part of the interval where oil, gas, and water are produced. The hybrid, underpressured area represents transition from oil, gas, and water production in eastern Ohio to gas and minor water production in the BCGA.

file:BasinCenteredGasFig12.jpg|{{figure number|10}}Composite pressure gradient showing pressure end members (normal, underpressuring, and overpressuring relationships) within the Clinton-Medina-Tuscarora interval (modified from Law et al.<ref name=Lawetal_1998a />).

file:BasinCenteredGasFig12.jpg|{{figure number|10}}Composite pressure gradient showing pressure end members (normal, underpressuring, and overpressuring relationships) within the Clinton-Medina-Tuscarora interval (modified from Law et al.<ref name=Lawetal_1998a />).

The underpressured reservoirs in the Clinton-Medina are interpreted to have undergone an earlier overpressured phase caused by the thermal transformation of oil to gas.<ref name=Lawanddickinson_1985 /><ref name=Lawandspencer_1993 /><ref name=Lawetal_1998a /><ref name=Ryderandzagorski_2003 /> Later, during a period of regional uplift accompanied by loss of gas and reservoir cooling, the overpressured, gas-bearing Clinton-Medina underwent a transition to an underpressuring phase. The overpressured, gas-bearing Tuscarora Sandstone reservoirs in central Pennsylvania are interpreted to be pressure remnants of the earlier overpressured phase in the Clinton-Medina.<ref name=Lawetal_1998a /><ref name=Ryderandzagorski_2003 />

The underpressured reservoirs in the Clinton-Medina are interpreted to have undergone an earlier overpressured phase caused by the thermal transformation of oil to gas.<ref name=Lawanddickinson_1985 /><ref name=Lawandspencer_1993 /><ref name=Lawetal_1998a /><ref name=Ryderandzagorski_2003 /> Later, during a period of regional uplift accompanied by loss of gas and reservoir cooling, the overpressured, gas-bearing Clinton-Medina underwent a transition to an underpressuring phase. The overpressured, gas-bearing Tuscarora Sandstone reservoirs in central Pennsylvania are interpreted to be pressure remnants of the earlier overpressured phase in the Clinton-Medina.<ref name=Lawetal_1998a /><ref name=Ryderandzagorski_2003 />