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The Clinton section in Wayne County represents a clastic wedge of the Lower Silurian Albian Group. It was deposited on the distal flank of the Appalachian basin as a result of the Taconic orogeny. The section extends vertically from the Queenston unconformity to the base of the Packer shell (Brassfield Limestone). It is primarily composed of sandstone, shale, limestone, and dolostone. Within this stratigraphic section, the sandstone facies is an important hydrocarbon reservoir rock. The sandstone facies pinches out laterally along a north-south depositional limit that is roughly located along the western boundary of Wayne County.
The study relied primarily on geophysical log data. However, drill cuttings were used to correlate lithologies to specific curve assemblages on the geophysical logs. This helped define lithologies to logs in areas where drill cuttings were lacking. Eight cross sections--four north-south and four east-west--show the complexity of the intertonguing clastic and carbonate deposits resulting from the progradation and shifting of deltaic and nearshore marine environments. The cross sections also show that the driller's terms of stray, red (1st), and white (2nd) Clinton sandstone are arbitrary units and are not temporally equivalent or correlative from well to well over great distances.
Stratigraphic interpretations indicate that the deposition of the Clinton section began with a marine transgression from the northwest across a subaerially exposed coastal plain that was deposited as the distal end of the Ordovician Queenston delta. This transgression reworked the upper Queenston sediments and redeposited them as calcareous silts and sands. Renewed uplift of the Taconic highlands caused a clastic influx into the areas and a relative regression of the sea. These sediments were deposited in prodeltaic and lower delta-plain environments. Some of the sediments were reworked offshore by ocean currents and wave action and redeposited as offshore bars. As the influx of Taconic sediment ended, muds were deposited, which were eventually transgressed by a carbonate-rich sea. A imestone unit, the Packer Shell, was then deposited ending the Alexandrian Epoch.
The structural setting is one of homoclinal dip to the southeast, with localized basement-controlled, minor folds normal to the basinal axis. Small-scale faulting can also be seen on structure maps of the base of the Packer Shell and the top of the Queenston. Local structural highs and faults affect oil and gas production in this mainly stratigraphic trap. Local structure commonly segregates the oil and gas in the same reservoir body.
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