Imaging the Morrow A Sandstone Using Shear Wave VSP Data, Postle Field, Oklahoma
Table 3
The proposed flow for processing the zero-offset and multioffset VSP datasets. A few processing techniques were introduced to preserve the original amplitude content of the data. (A) The zero-offset shear wave dataset, (B) the zero-offset compressional dataset, and (C) the multioffset shear wave dataset.
Processing steps
(A)
(B)
(C)
1 Input VSP data and loading geometry on data headers
X
X
X
(2) Vibroseis sweep correlation and removing high frequency noises.
X
X
X
(3) -wave first break arrivals
X
X
(4) Hodogram analysis on -wave arrivals from a far vertical source
(5) Hodogram analysis on -wave arrivals from a few horizontal sources
X
(6) 3C amplitude analysis
X
X
(7) Receiver reorientation
X
X
(8) Fixing vibrator polarity
X
X
(9) Rotating data to the local coordinate system (radial-transverse)
X
(10) Calculating inclination of transmitted shear wave for each receiver
X
(11) Tilting each receiver based on calculated inclination
X
(12) 2C rotation analysis
X
(13) Alford rotation analysis
X
(14) Rotating data to the natural coordinate system
X
(15) Creating velocity model and true amplitude recovery
X
X
X
(16) Applying median filter to isolate upgoing shear wave
X
(17) Applying dual median filter* to isolate desirable upgoing wave
X
X
(18) Applying deconvolution filter on upgoing waves using downgoing waves
X
X
(19) Aligning upgoing events and making corridor stack
X
X
(20) Normalizing amplitude for different shots
X
(21) Applying VSP-CDP transformation on 2D VSP lines
