Changes

  | part    = Predicting the occurrence of oil and gas traps

  | part    = Predicting the occurrence of oil and gas traps

  | chapter = Interpreting 3-D seismic data

  | chapter = Interpreting 3-D seismic data

  | frompg  = 13-1

  | frompg  = 13-19

  | author  = Geoffrey A. Dorn

  | author  = Geoffrey A. Dorn

  | link    = http://archives.datapages.com/data/specpubs/beaumont/ch13/ch13.htm

  | link    = http://archives.datapages.com/data/specpubs/beaumont/ch13/ch13.htm

  | isbn    = 0-89181-602-X

  | isbn    = 0-89181-602-X

}}

}}

Additional refinement to the [[3-D seismic: time and horizon slices|horizon-slice]] approach can be made to accommodate situations where there is growth, or differential deposition, in an interval between two interpreted horizons. For such an interval, the reflections between the two interval-bounding horizons are not parallel to either bounding horizon. To some extent, the shape of the reflections in this interval is intermediate between the shapes of the interval bounding horizons. A set of slices between the two bounding horizons, which more closely mimics the shape of the reflections in that interval, is given by

Additional refinement to the [[3-D seismic: time and horizon slices|horizon-slice]] approach can be made to accommodate situations where there is [[growth fault|growth]], or differential deposition, in an interval between two interpreted horizons. For such an interval, the reflections between the two interval-bounding horizons are not parallel to either bounding horizon. To some extent, the shape of the reflections in this interval is intermediate between the shapes of the interval bounding horizons. A set of slices between the two bounding horizons, which more closely mimics the shape of the reflections in that interval, is given by

:<math>S = H_{1} + R*(H_{2} - H_{1})</math>

:<math>S = H_{1} + R \times (H_{2} - H_{1})</math>

where:

where:

==Definition==

==Definition==

The new surface, ''S'', is the shallower horizon time structure plus a fraction of the isochron between the two bounding horizons. Such a slice is called a '''proportional slice''' because it is proportionally between the two bounding horizons. In certain environments that exhibit significant growth in the interval, the proportional slice can provide a significantly improved image of the depositional stratigraphy compared to horizon slices in the shape of either bounding horizon.

The new surface, ''S'', is the shallower horizon time structure plus a fraction of the [[isochron]] between the two bounding horizons. Such a slice is called a '''proportional slice''' because it is proportionally between the two bounding horizons. In certain environments that exhibit significant [[growth]] in the interval, the proportional slice can provide a significantly improved image of the depositional stratigraphy compared to horizon slices in the shape of either bounding horizon.

==Creating proportional slices==

==Creating proportional slices==

==See also==

==See also==

* [[Time and horizon slices]]

* [[3-D seismic: time and horizon slices]]

==External links==

==External links==

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

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

[[Category:Interpreting 3-D seismic data]]

[[Category:Interpreting 3-D seismic data]]