Seismic facies analysis
|Exploring for Oil and Gas Traps|
|Series||Treatise in Petroleum Geology|
|Part||Predicting the occurrence of oil and gas traps|
|Chapter||Exploring for stratigraphic traps|
|Author||John C. Dolson, Mike S. Bahorich, Rick C. Tobin, Edward A. Beaumont, Louis J. Terlikoski, Michael L. Hendricks|
Seismic facies are "mappable, three dimensional seismic units composed of groups of reflections whose parameters differ from those of adjacent facies units”. Seismic facies analysis is the description and interpretation of seismic reflection parameters, such as configuration, continuity, amplitude, and frequency, within the stratigraphic framework of a depositional sequence. Its purpose is to determine all variations of seismic parameters within third-order sequences and their systems tracts in order to determine lateral lithofacies and fluid type changes. Of these parameters, reflection pattern geometries are perhaps the most useful for calibration with lithofacies interpreted from well logs, cores, and cuttings.
There are five useful reflection parameters:
Depositional environment, sediment source, and lithofacies can be interpreted by grouping these parameters into mappable, three-dimensional seismic facies. The table below summarizes the information obtained from each parameter.
|Reflection parameter||Geologic interpretation|
Seismic facies analysis procedure
- Divide each depositional sequence into seismic facies units on all seismic sections.
- Describe the internal reflection configuration and terminations of each seismic facies unit, i.e., sigmoid, parallel, downlap.
- Transfer seismic facies descriptions from seismic sections to a shot point map of each sequence.
- Combine seismic facies distribution and thickness with the map distribution of any other diagnostic parameters, such as interval velocity or localized amplitude anomalies.
- Integrate well and outcrop data with seismic facies distribution.
- Interpret the seismic facies maps in terms of depositional settings such as marine or nonmarine, water depth, basin position, energy, transport direction, or any other depositional aspects.
- Estimate lithology using depositional setting interpretation from step 6 and all available data.
- Seismic facies analysis
- Reflection configuration patterns
- Seismic facies mapping
- Analyzing individual reflectors
- Techniques for enhancing seismic facies analysis
- Analyzing lithofacies
- Petrophysical analysis of lithofacies
- Mitchum, R., M., Vail, P., R., Sangree, J., B., 1977, Seismic stratigraphy and global changes in sea level, part 6: stratigraphic interpretations of seismic reflection patterns in depositional sequences, in Payton, C., E., ed., Seismic Stratigraphy and Applications to Hydrocarbon Exploration: AAPG Memoir 26, p. 117–133.
- Vail, P., R., 1987, Seismic stratigraphy interpretation procedure, in Bally, A., W., ed., Atlas of Seismic Stratigraphy: AAPG Studies in Geology No. 27, p. 2.
- Zeng, Hongliu, 2013, Frequency-dependent seismic-stratigraphic and facies interpretation: AAPG Bulletin, v. 97, no. 2, p. 201–221, DOI:10.1306/06011212029.
- Bally, A., W., ed., 1987, Atlas of Seismic Stratigraphy: AAPG Studies in Geology 27, vol. 1, 124 p.