4:14 The challenge
- →Re-enter a legacy well for permanent P&A by locating its casing stump.
- →Target casing stump near ~1,008–1,013 ft MD with uncertain position.
- →MWD magnetometers saturated near the stump, the strongest-signal zone was unusable.
Our solution
Passive magnetic ranging with gyro surveys homed in on the casing stump. Where the MWD magnetometers saturated near the source, Gunnar reconstructed the magnetic field theoretically to fill the gap and resolve distance and direction to the target.
Casing stump located to ~1 ft, re-entry for permanent P&A
The result
~1 ft
to target, casing stump located at ~1,010 ft MD
- ·Passive ranging + gyro located the casing stump at ~1,008–1,013 ft MD
- ·Distance to target ~0.7–1.3 ft; azimuth resolved
- ·Overcame MWD magnetometer saturation via theoretical field reconstruction
- ·Set up the milled re-entry for permanent plug & abandonment
Ranging
PMR
Deployment
BHA While Drilling / Wireline
Re-entry
Yes
Location
Colorado, USA
Year
2023
Watch, related footage
Full video library → 4:14 
7:02 Intersecting Two Abandoned Wells Under Los Angeles (Part 1) | P&A Case Study
4:22