The Time Slice Versus the Statistical Slice: A Comparison of Their Uses for 3-D Seismic Interpretation

John Kerr and Gary L. Jones

Time slices show seismic events in their structure context, separating chaotic events (such as salt structures) from parallel to subparallel seismic events (such as sediments). However, since time slices consist of samples that occur at a single time, they cannot render complete seismic events, which are composed of entire wavelets.

Statistical slices are seismic attribute maps calculated over a window that is centered on a particular time. They can be calculated using a variety of different statistics and attributes, including RMS amplitude, maximum/minimum amplitude, average amplitude, and continuity. Calculating these attributes over a window allows the interpreter to statistically evaluate a wavelet instead of a single sample. The size of the window determines the amount of the seismic wavelet analyzed.

Seismic attribute calculations do not need to conform to horizon structure. Therefore, the interpreter can produce statistical slices from the top to the bottom of any seismic cube volume before doing any interpretation. The interpreter can compare the resulting statistical slices to the corresponding time slices for the entire range of data in the volume.

Differing attributes can reveal structural and stratigraphic details that are not visible on a time slice. Examples include fault patterns, channels, and gas-oil contacts.

AAPG Search and Discover Article #91019©1996 AAPG Convention and Exhibition 19-22 May 1996, San Diego, California