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 
Link  Web page 
Store  AAPG Store 
Seismic facies are "mappable, three dimensional seismic units composed of groups of reflections whose parameters differ from those of adjacent facies units”.^{[1]} 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 thirdorder sequences and their systems tracts in order to determine lateral lithofacies and fluid type changes.^{[2]} Of these parameters, reflection pattern geometries are perhaps the most useful for calibration with lithofacies interpreted from well logs, cores, and cuttings.
Reflection parameters
There are five useful reflection parameters:
 Configuration (reflection geometry)
 Continuity
 Amplitude
 Frequency
 Interval velocity
Depositional environment, sediment source, and lithofacies can be interpreted by grouping these parameters into mappable, threedimensional seismic facies.^{[4]} The table below^{[1]} summarizes the information obtained from each parameter.
Reflection parameter  Geologic interpretation 

Configuration 

Continuity 

Amplitude 

Frequency 

Interval velocity 

Seismic facies analysis procedure
The table below outlines a procedure to analyze seismic facies from a grid of sections (vertical) of 2D or 3D seismic data (modified from ^{[1]}).
 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.
See also
 Seismic facies analysis
 Reflection configuration patterns
 Seismic facies mapping
 Analyzing individual reflectors
 Techniques for enhancing seismic facies analysis
 Analyzing lithofacies
 Petrophysical analysis of lithofacies
References
 ↑ ^{1.0} ^{1.1} ^{1.2} 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, Frequencydependent seismicstratigraphic 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.