Natural Gas Production from Ordovician Queenston Formation in West Auburn Field, Cayuga County, New York

Terry L. Ward

Gas has been produced from the Upper Ordovician Queenston Formation at West Auburn field, Cayuga County, New York, for over 20 years. This field indicates Queenston production to be long lived, with substantially economic reserves found at depths shallower than 2,000 ft. Locally, the Queenston is comprised of sand and silty shale with the primary reservoirs found in quartzose sandstones. The overall thickness of the Queenston clastic interval is over 700 ft with gas found in the upper 300 ft.

Three primary gas sands are continuous across the field area and have high average porosities of as much as 13.0% and average permeabilities of 0.20 md. Extreme examples show peak porosities approaching 20% and permeabilities of over 5.0 md. The reservoir is composed of very fine to medium-grained, moderately sorted, red sandstone. Sand grains are predominantly quartz with minor amounts of feldspar. The main pore-filling constituent is abundant authigenic clay with iron oxides, thus contributing to reduced permeabilities. These sands vary in reservoir quality through the field and, hence, allow for stratigraphic trapping of the gas.

Other factors involved include the updip accumulation of gas against the Silurian-Ordovician unconformity at the top of the Queenston. Some of the pay sands are absent due to this unconformity in the area farthest updip and, therefore, decrease the overall reserve potential of the individual well in that part of the field.

Regional structure consists of a gentle southeasterly dip. Minor folds within the field contribute to the natural fracturing of this low-permeability reservoir. Additionally, isolated low-displacement faults tend to yield above-average naturally flowing wells and may induce production from formations other than the Queenston.

Development of Queenston reservoirs presently covers four central New York counties and continued exploration will undoubtedly discover new fields. In the development stage, drill sites should be selected to take advantage of both the higher porosity sand units and possible natural fracturing from minor folds and faults.

AAPG Search and Discovery Article #91031©1988 AAPG Eastern Section, Charleston, West Virginia, 13-16 September 1988.