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Decollement in the southern Allegheny Plateau of Pennsylvania

Howard A. Pohn·Terri L. Purdy
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Abstract

Recent field investigations in the Allegheny Plateau north of Williamsport, Pennsylvania have shown the presence of both southward dipping, low-angle thrust faults translated to the north and northward dipping back or antithectic thrusts translated to the south at the leading (north) edge of Barclay syncline. The presence of these thrusts, along with reported anomalous dips along the leading edge of the next syncline to the south (the Bernice or Barbours syncline) may indicate that the Allegheny Plateau of Pennsylvania is underlain by master decollement and that this decollement gives rise to a series of splay thrusts. In some cases such as the Barclay syncline, the combination of these forward and back thrust faults may serve as fracture porosity traps.

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Howard A. Pohn, Terri L. Purdy. 1979. Decollement in the southern Allegheny Plateau of Pennsylvania. https://doi.org/10.3133/ofr791321

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