Reliable gas hydrate characterization from seismic data is a key step in understanding and ultimately developing the nation’s hydrate resource. The hydrate-rich areas will be the first targets for commercial development. If even 1% of this gas could be produced, it would be more than double current U.S. proven natural gas reserves, thus benefiting gas customers, creating jobs in the United States, and reducing our dependence on imported energy. Accurate characterization of worldwide hydrate accumulations also will benefit environmental researchers by providing data for climate models and helping to guide public policy with regard to climate change.
This project will provide a new, seismic-based technology for detecting and appraising hydrate distribution and the nature of the associated geologic sediments and structures. By integrating geology, 3-D seismic, well logs, and rock physics, we can accurately assess the volume of gas hydrate over broad regions. The major advantage of this method is that it uses conventional 3-D seismic and well log data as inputs. No special tools or acquisition methods are needed; hence, the method will be economical and practical to apply.
The method the researchers propose is based on the computation of cumulative seismic attributes (CATTs) and its calibration to in situ data from well logs and/or core measurements. CATTs is fundamentally different from other seismic reservoir characterization methods such as amplitude-versus-offset and acoustic impedance inversion. It is designed to respond to multiple stacked layers of hydrocarbon-filled zones, and, unlike most seismic attributes, well-suited to calibration with well log data. The unique advantage of CATTs is its ability to be used in areas where the thickness of the hydrocarbon-bearing intervals is below standard seismic resolution.