Well geophysics

Question 1

Conventional VSP configuration

Answer 1

Receivers in wellbore: multicomponent receivers, clamped against borehole wall
Source:
close-by (“Zero-offset”) or at a distance
Offshore : airgun(s)
Onshore : airgun, Vibrator, dynamite
Borehole:
Preference for cased and cemented hole

Question 2

Principles of VSP processing

Answer 2

separate up going from downgoing
Process : Pass ONLY Horizontal events
FK Passband - horizontal events only

Question 3

Key steps VSP processing

Answer 3

• Summing of common depth records
• Removal of tube waves
• Separation up- and down-going wavefields
• Deconvolution
• Corridor stack
• VSP - CDP Transform if needed