Overview:
- Pumps On surveys have shown to be helpful to identify magnetic mud
- Sensitivity Analysis should be performed to help determine wellbore position error
- Avoid unnecessary trips caused by directional survey QC failure
- Pumps On surveys can help confirm SFE correction performed with MSA
- Basic survey QC failure doesn’t always represent significant azimuth error and
vice versa
What is Magnetic Mud?
- The term “magnetic mud” is often used when magnetic material is retained
within the mud, influencing the accuracy of directional MWD measurements
- The magnetic field is attenuated through the magnetic mud resulting in a
scale factor error on the cross axial magnetometers
Directional MWD Survey QC
- Basic Survey QC acceptance criteria
- Gtotal +/- 0.003
- Btotal (magnetic field strength) +/- 300nT
- Dip (magnetic field inclination) +/- 0.30 deg
....
View the entire Presentation:
A Quick Method to Identify Magnetic Mud
Timothy Allen - Sperry Drilling