David Dominic (Committee Member), Ernest Hauser (Committee Member), Doyle Watts (Advisor)
Master of Science (MS)
The Smoothed Pseudo Wigner-Ville Distribution (SPWVD) is one method to simultaneously resolve time series in both time and frequency domains, allowing determination of frequency variation with time in non-stationary signals. Also, SPWVD reduces the cross-term interference. This analysis was applied to stacked, migrated seismic reflection data from Ohio to characterize gas shadows produced by known and potential gas reservoirs in the Clinton interval. In northeast Ohio, the Clinton interval is identified as occurring immediately beneath the Dayton Limestone, which is known as the driller’s Packer Shell in the subsurface. The analysis was first applied to a seismic reflection line acquired from the East Dominion Ohio Gas Storage field that contained an example of a gas shadow. This analysis demonstrated that all frequencies were attenuated at otherwise continuous reflectors immediately beneath a portion of the Clinton interval fully charged with natural gas. There was no enhancement of low frequencies such as described in low frequency shadows from the Gulf of Mexico. This analysis was applied to other seismic lines acquired in areas where natural gas is produced from the Clinton interval and areas of possible natural gas attenuation were identified. In this work, low frequencies are not enhanced beneath the potential gas reservoir. To be successful, this method requires that continuous reflectors occur beneath the target horizon. Simple attenuation of signal from a continuous reflector may be a new direct indicator of natural gas on seismic reflection data from Ohio and other Paleozoic basins.
Department or Program
Department of Earth and Environmental Sciences
Year Degree Awarded
Copyright 2016, all rights reserved. My ETD will be available under the "Fair Use" terms of copyright law.