Changes

  | part    = Predicting the occurrence of oil and gas traps

  | part    = Predicting the occurrence of oil and gas traps

  | chapter = Exploring for stratigraphic traps

  | chapter = Exploring for stratigraphic traps

  | frompg  = 21-1

  | frompg  = 21-35

  | topg    = 21-68

  | topg    = 21-36

  | author  = John C. Dolson, Mike S. Bahorich, Rick C. Tobin, Edward A. Beaumont, Louis J. Terlikoski, Michael L. Hendricks

  | author  = John C. Dolson, Mike S. Bahorich, Rick C. Tobin, Edward A. Beaumont, Louis J. Terlikoski, Michael L. Hendricks

  | link    = http://archives.datapages.com/data/specpubs/beaumont/ch21/ch21.htm

  | link    = http://archives.datapages.com/data/specpubs/beaumont/ch21/ch21.htm

  | isbn    = 0-89181-602-X

  | isbn    = 0-89181-602-X

}}

}}

'''Seismic facies''' are "mappable, three dimensional seismic units composed of groups of reflections whose parameters differ from those of adjacent facies units”.<ref name=ch21r31>Mitchum, R., M., Vail, P., R., Sangree, J., B., 1977, [http://archives.datapages.com/data/specpubs/seismic1/data/a165/a165/0001/0100/0117.htm 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: [http://store.aapg.org/detail.aspx?id=1157 AAPG Memoir 26], p. 117–133.</ref> 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.<ref name=ch21r44>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.</ref>

'''Seismic facies''' are "mappable, three dimensional seismic units composed of groups of [[Reflection configuration patterns|reflections]] whose parameters differ from those of adjacent facies units”.<ref name=ch21r31>Mitchum, R., M., Vail, P., R., Sangree, J., B., 1977, [http://archives.datapages.com/data/specpubs/seismic1/data/a165/a165/0001/0100/0117.htm 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: [http://store.aapg.org/detail.aspx?id=1157 AAPG Memoir 26], p. 117–133.</ref> Seismic facies analysis is the description and interpretation of seismic reflection parameters, such as configuration, continuity, [http://wiki.seg.org/wiki/Dictionary:Amplitude amplitude], and [http://wiki.seg.org/wiki/Dictionary:Frequency 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.<ref name=ch21r44>Vail, P., R., 1987, [http://archives.datapages.com/data/specpubs/oversiz2/data/a188/a188/0001/0000/0001.htm Seismic stratigraphy interpretation procedure], in Bally, A., W., ed., Atlas of Seismic Stratigraphy: [http://store.aapg.org/detail.aspx?id=478 AAPG Studies in Geology No. 27], p. 2.</ref> Of these parameters, [[Reflection configuration patterns|reflection pattern]] geometries are perhaps the most useful for calibration with lithofacies interpreted from [[Quick-look lithology from logs|well logs]], [[Core description|cores]], and [[Mudlogging: drill cuttings analysis|cuttings]].

 

==Reflection parameters==

==Reflection parameters==

* Configuration (reflection geometry)

* Configuration (reflection geometry)

* Continuity

* Continuity

* Amplitude

* [http://wiki.seg.org/wiki/Dictionary:Amplitude Amplitude]

* Frequency

* [http://wiki.seg.org/wiki/Dictionary:Frequency Frequency]

* Interval velocity

* [http://wiki.seg.org/wiki/Dictionary:Interval_velocity Interval velocity]

Depositional environment, sediment source, and lithofacies can be interpreted by grouping these parameters into mappable, three-dimensional seismic facies.<ref name=ch21r5>Bally, A., W., ed., 1987, Atlas of Seismic Stratigraphy: AAPG Studies in Geology 27, vol. 1, 124 p.</ref> The table below (after <ref name=ch21r31 />) summarizes the information obtained from each parameter.

[[Depositional environments|Depositional environment]], sediment source, and [[lithofacies]] can be interpreted by grouping these parameters into mappable, three-dimensional seismic facies.<ref name=ch21r5>Bally, A., W., ed., 1987, Atlas of Seismic Stratigraphy: [http://store.aapg.org/detail.aspx?id=478 AAPG Studies in Geology 27], vol. 1, 124 p.</ref> The table below<ref name=ch21r31 /> summarizes the information obtained from each parameter.

{| class = "wikitable"

{| class = "wikitable"

| Amplitude

| Amplitude

|

|

*  Velocity-density contrasts of individual interfaces  

*  Velocity and density contrasts of individual interfaces  

*  Bed spacing  

*  Bed spacing  

*  Bed thickness

*  Bed thickness

The table below outlines a procedure to analyze seismic facies from a grid of sections (vertical) of 2-D or 3-D [[seismic data]] (modified from <ref name=ch21r31 />).

The table below outlines a procedure to analyze seismic facies from a grid of sections (vertical) of 2-D or 3-D [[seismic data]] (modified from <ref name=ch21r31 />).

# Divide each [[Depositional sequence identification|depositional sequence]] into seismic facies units on all seismic sections.

# Describe the internal [[Reflection configuration patterns|reflection configuration]] and terminations of each seismic facies unit, i.e., sigmoid, parallel, [http://www.glossary.oilfield.slb.com/en/Terms/d/downlap.aspx 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 [http://wiki.seg.org/wiki/Dictionary:Interval_velocity interval velocity] or localized [http://wiki.seg.org/wiki/Dictionary:Amplitude_anomaly amplitude anomalies].

# Integrate well and [http://www.merriam-webster.com/dictionary/outcrop 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.

| Divide each depositional sequence into seismic facies units on all seismic sections.

# Estimate lithology using depositional setting interpretation from step 6 and all available data.

| 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==

==See also==

* [[Facies analysis]]

* [[Seismic facies analysis]]

* [[Reflection configuration patterns]]

* [[Reflection configuration patterns]]

* [[Seismic facies mapping]]

* [[Seismic facies mapping]]

[[Category:Predicting the occurrence of oil and gas traps]]  

[[Category:Predicting the occurrence of oil and gas traps]]  

[[Category:Exploring for stratigraphic traps]]

[[Category:Exploring for stratigraphic traps]]