View source for Seismic data: identifying reflectors

{{publication 
 | image   = exploring-for-oil-and-gas-traps.png
 | width   = 120px
 | series  = Treatise in Petroleum Geology
 | title   = Exploring for Oil and Gas Traps
 | part    = Predicting the occurrence of oil and gas traps
 | chapter = Interpreting seismic data
 | frompg  = 12-18
 | topg    = 12-18
 | author  = Christopher L. Liner
 | link    = http://archives.datapages.com/data/specpubs/beaumont/ch12/ch12.htm
 | pdf     = 
 | store   = http://store.aapg.org/detail.aspx?id=545
 | isbn    = 0-89181-602-X
}}
Whether using[[vertical seismic profile| VSP]], [[synthetic seismogram]], or [[log overlay]], the final step is to compare the object to [[seismic trace]]s in the vicinity of the well and find a fit.

==Example==

[[file:interpreting-seismic-data_fig12-8.png|300px|thumb|{{figure number|1}}Sonic log converted to time and velocity. From Liner;<ref name=Liner1999>Liner, C., 1999, Elements of 3-D Seismology: Tulsa, PennWell.</ref> courtesy PennWell.]]

In [[:file:interpreting-seismic-data_fig12-8.png|Figure 1]], a [[Basic open hole tools#Sonic|sonic]] log has been converted to time and velocity. Note that the time axis on the seismic section and the converted sonic log are linear, while the depth tick marks on the sonic are nonlinear. The geological horizons annotated on the sonic log are located via the depth ticks from picks on other logs ([[Basic open hole tools#Resistivity|electric]], [[Basic open hole tools#Gamma ray|gamma ray]], etc.). It is important to realize that a sonic log never goes to the surface; there is always a gap for the [[surface casing]]. We do not expect time zero on the converted log to fit at time zero on the seismic section. In practice, the log is placed over the seismic section and shifted vertically until we are satisfied with the fit.

==See also==
* [[Seismic data: building a stratigraphic model]]
* [[Synthetic seismogram]]
* [[Synthetic seismograms: correlation to other data]]

==References==
{{reflist}}

==External links==
{{search}}
* [http://archives.datapages.com/data/specpubs/beaumont/ch12/ch12.htm Original content in Datapages]
* [http://store.aapg.org/detail.aspx?id=545 Find the book in the AAPG Store]

[[Category:Predicting the occurrence of oil and gas traps]] 
[[Category:Interpreting seismic data]]
[[Category:Exploring for stratigraphic traps]]
[[Category:Exploring for structural traps]]