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  | isbn    = 0-89181-602-X

  | isbn    = 0-89181-602-X

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By interpreting depositional sequences in the seismic and well log data separately discontinuities are identified as objectively as possible on the seismic and log sections before they are tied together using the [[synthetic seismogram]].<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>

By interpreting [[Depositional sequence definition|depositional sequences]] in the [[Seismic data|seismic]] and [[Basic open hole tools|well log]] data separately, discontinuities are identified as objectively as possible on the seismic and log sections before they are tied together using the [[synthetic seismogram]].<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>

==Objectives==

==Objectives==

* To link well log depths to seismic section times.

* To link well log depths to seismic section times.

* To develop an understanding of the causes of constructive and destructive interference patterns of individual wavelets originating from acoustic impedance contrasts.

* To develop an understanding of the causes of constructive and destructive [http://wiki.seg.org/wiki/Dictionary:Interference interference] patterns of individual wavelets originating from [http://wiki.seg.org/wiki/Dictionary:Acoustic_impedance acoustic impedance] contrasts.

==Using synthetic seismograms==

==Using synthetic seismograms==

The composite synthetic seismic trace from a synthetic seismogram relates depth information from logs to seismic time. The plots of individual wavelets in a synthetic seismogram show how each impedance interface contributes to the individual reflections. Vail<ref name=ch21r44 />) recommends that seismic sequence analysis and well log sequence analysis be started independently so that boundaries be interpreted as objectively as possible before they are tied together by a synthetic seismogram.

The composite synthetic seismic trace from a [[synthetic seismogram]] relates depth information from logs to seismic time. The plots of individual wavelets in a synthetic seismogram show how each impedance interface contributes to the individual reflections. Vail<ref name=ch21r44 />) recommends that seismic sequence analysis and well log sequence analysis be started independently so that boundaries be interpreted as objectively as possible before they are tied together by a synthetic seismogram.

[[:file:exploring-for-stratigraphic-traps_fig21-22.png|Figure 1]] is an example of a synthetic seismogram from the Midland basin, Texas.

[[:file:exploring-for-stratigraphic-traps_fig21-22.png|Figure 1]] is an example of a synthetic seismogram from the Midland basin, Texas.

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| Adjust depositional sequence and systems tract boundaries to the best solution using the ties made in step 2.

| Adjust depositional sequence and [[Definitions_of_depositional_system_elements#Systems_tracts|systems tract]] boundaries to the best solution using the ties made in step 2.

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==Example of integrating synthetics==

==Example of integrating synthetics==

[[Synthetic seismogram]]s, or synthetics, can be interactively tied to log, lithologic, and seismic data on geological workstations. [[:file:exploring-for-stratigraphic-traps_fig21-23.png|Figure 2]] illustrates an example from the Gulf of Suez basin. A wavelet trough forms at a sequence boundary (T55) overlain and sealed by anhydrite and salt. A pronounced wavelet peak forms on an underlying maximum flooding surface. The intervening sequence consists of a lobate deltaic fan formed during a relative high-stand. The transgressive systems tract is thin to absent. The geometry of the fan is clear from the well log and seismic integration.

[[Synthetic seismogram]]s, or synthetics, can be interactively tied to log, lithologic, and seismic data on geological workstations. [[:file:exploring-for-stratigraphic-traps_fig21-23.png|Figure 2]] illustrates an example from the Gulf of Suez basin. A wavelet trough forms at a [[Definitions_of_depositional_system_elements#Sequence_boundaries|sequence boundary]] (T55) overlain and sealed by [[anhydrite]] and [[Evaporite|salt]]. A pronounced wavelet peak forms on an underlying [[Definitions_of_depositional_system_elements#Maximum_flooding_surface|maximum flooding surface]]. The intervening sequence consists of a lobate [[Lithofacies_and_environmental_analysis_of_clastic_depositional_systems#Deltas|deltaic fan]] formed during a relative [[Sea_level_cycle_phase_and_systems_tracts#Highstand_systems_tracts|highstand]]. The [[Sea_level_cycle_phase_and_systems_tracts#Transgressive_systems_tracts|transgressive systems tract]] is thin to absent. The geometry of the fan is clear from the well log and seismic integration.