In seismic, there are two kind of resolution. vertical resolution (temporal) and lateral resolution (spatial).
Vertical resolution is defined as ¼ seismic wavelength ( λ ), where λ= v/ f , v is sonic wave velocity and f is frequency, where usually dominant frequency (fdom) is used.
image courtesy of http://ensiklopediseismik.blogspot.com
if fdom 25 Hz velocity 2500m/s then the minimum thickness that can be separated on seismic is 25 meter
To separate thin layer below seismic resolution, we can restore atenuated high frequency using high frequency restoration method using VSP data.If the VSP data is unavailable, we still can boost up high frequency using high frequency enhancement.
Well resolution is far above seismic resolution. This would become a problem when we want to do well seismic tie especially on thin layer beyond seismic resolution. Some trick to tie over the problem is lowering the well frequency or restoring / enhancing seismic high frequency. Restoreing / enhancing seismic high frequency is prefered since no data is eleminated / reduced thus we can preserve the information contained.
Seismic High Frequency Enhancement. Note the dominan frequency on the amplitude spectrum after enhancement slide over 40 Hz
Seismic section before and after High Frequency Enhancement. note the thin layer separation.
Seismic section before and after High Frequency Enhancement and post-stack enhancement. note the thin layer separation and reflector continuity are both enhanced.
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