|Exploring for Oil and Gas Traps|
|Series||Treatise in Petroleum Geology|
|Part||Predicting the occurrence of oil and gas traps|
|Chapter||Exploring for structural traps|
|Author||R.A. Nelson, T.L. Patton, S. Serra|
Seismic data provide a “time picture” of subsurface structure. For accurate structural analysis, an effort should be made to convert the time data to depth.
There are three types of seismic data:
- Reflection (including 2-D and 3-D)
- Shear wave
2-D reflection seismic data provide cross-sectional views in both the dip and strike directions. Data on the lines are a mixture of both in-plane and out-of-plane reflectors. 2-D reflection seismic data are most important in the earlier stages of an exploration program, especially in frontier basins.
3-D reflection seismic data provide resolved cross-sectional views along any azimuth within the survey area. Time “slices” (maps) on any horizon can also be generated. The nature and location of out-of-plane features can be more accurately determined. Because of the high acquisition costs, 3-D seismic techniques normally are used only to more accurately define individual prospects.
Shear wave data, in combination with conventional compressional wave data, can provide information on lithology, fractures, and the presence of hydrocarbons.
Refraction seismic data provide a deep crustal view of gross structure (basin scale to lithosphere-upper mantle scale), which is useful when trying to understand regional tectonics.
How to use it
Structural interpretation from seismic data is indeed a difficult endeavor; the following are hints for effective interpretation procedures.
- Interpretation on each line should proceed from well-imaged, well-constrained portions of the line toward areas of poorer constraint. Use symbols for varying quality of interpretation.
- Map multiple horizons.
- Map and contour fault surfaces critical to closure.
- Integrate fault and horizon contours.
- In thrust, rift, and extensional terranes, emphasize dip line interpretation; in foreland and wrench terranes, equally emphasize strike line interpretation.
- Generate depth conversions during iterative interpretations.
Examples of use
- Valderrama, M., H., Nielsen, K., C., McMechan, G., A., 1996, Three-dimensional seismic interpretation from the triangle zone of the frontal Ouachita Mountains and Arkoma basin, Pittsburg County, Oklahoma: AAPG Bulletin, vol. 80, p. 1185–1202.
- Telford, W., M., Geldart, L., P., Sheriff, R., E., 1990, Applied Geophysics: Cambridge, Cambridge University Press, 770 p.
- Brown, A., R., 1996, Interpretation of three-dimensional seismic data: AAPG Memoir 42, 4th ed., 424 p.
- Bally, A., W., ed., 1983, Seismic Expression of Structural Styles, A Picture and Work Atlas: AAPG Studies in Geology 15, 3 vols.
- Badley, M., E., 1985, Practical seismic interpretation: Boston, International Human Resources Development Corp., 266 p.
- Slotboom, R., T., Lawton, D., C., Spratt, D., A., 1996, Seismic interpretation of the triangle zone at Jumping Pond, Alberta: Bulletin of Canadian Petroleum Geology, vol. 44, p. 233–243.
- Sheriff, R., E., 1982, Structural Interpretation of Seismic Data: AAPG Education Course Notes 23, 73 p.
- Fraser, A., J., Gawthorpe, R., L., 1990, Tectono-stratigraphic development and hydrocar-bon habitat of the Carboniferous in northern England, in Hardman, R., F., P., Brooks, J., eds., Tectonic Events Responsible for Britain's Oil and Gas Reserves: Geological Society of London Special Publication 55, p. 49–86.
- Coffeen, J., A., 1984, Interpreting seismic data workbook: Tulsa, PennWell Publishing Co., 196 p.
- Forward modeling of seismic data
- Displaying seismic data
- Seismic data - creating an integrated structure map
- Seismic data: building a stratigraphic model
- Seismic data acquisition on land
- Marine seismic data acquisition
- Seismic interpretation
- Seismic inversion
- Seismic migration
- Seismic processing basics
- Vertical and lateral seismic resolution and attenuation
- Three-dimensional seismic method
- 3-D seismic data: the data cube
- Components of a 3-D seismic survey
- 3-D seismic data views
- Seismic data - mapping with two-dimensional data
- Phases of a seismic project
- Seismic data interpretation - recurring themes