Abstract: Cyclone Reef 3D Seismic Study

MORRIS, JAMES R.

A 3D seismic survey was acquired over the Cyclone Onondaga Pinnacle Reef in Mckean County, Pennsylvania in December of 1995. The major objective of this survey was to identify areas of enhanced reservoir quality, either in the form of high porosity, or greater reservoir thickness. Once identified, this data would be utilized to improve reservoir development for the purpose of converting this reef to a natural gas storage facility.

Seismic modeling, done in conjunction with the 3D seismic interpretation, concluded that unique measurement of areas of enhanced porosity or true reservoir thickness would not be possible. This was due to the severely band limited frequency content of the 3D seismic data, and strong seismic interference among the Hamilton, Onondaga, and Helderberg reflectors.

Of surprise, were the seven fault planes identified within and around the reef. Four of these are compressional thrust faults southeast of the reef, while the other three appear to be normal or listric faults which have seperated the structurally lower, eastern part of the reef from the existing producing wells to the west. An isochron between the Hamilton and Onondaga reflectors suggest that the eastern part of the reef was as high as the western part immediately after burial. An offset well is planned for the summer of 1997 to test the eastern part of the reef for untapped natural gas reserves.

AAPG Search and Discovery Article #90939©1997 AAPG Eastern Section and TSOP, Lexington, Kentucky