Lateral Survey Enhancements

Manage Positional Uncertainty for Precise Well Placement

With accurate azimuthal surveys, directional drillers can maximize the efficiency of operations by drilling close to lease lines and landing in smaller targets according to plan. Schlumberger azimuthal optimization surveys provide the real-time measurements and answers that enable this precise well placement and verify the quality of MWD azimuthal measurements. The GRS geomagnetic referencing service, used worldwide, applies local magnetic field effects at the drillsite to magnetic directional survey data. The GRS service reduces drilling risk with enhanced survey accuracy and reduces the errors that contribute to the positional uncertainty of the well path.

About GRS geomagnetic referencing

• No disruption of drilling operations
• Real-time wellbore positioning
• Correction and modeling for magnetic field components—main, crustal, and disturbance
• Time and depth varying reference
• Real-time diurnal correction using magnetic observatory (if necessary)
• Correction for drillstring interference, including BHA magnetization and BHA sag or deflection
• Multitiered approach tailored to local challenge/budget
• Survey of local crustal variations that can be used for adjacent wells
• Real-time magnetic observatory data for optimal accuracy

Reducing the ellipsoid of uncertainty & landing on target

The primary benefit of surveying is confidence in positioning the wellbore within the ellipsoid of uncertainty (EOU). With GRS services, the EOU is significantly reduced to give directional drillers pinpoint accuracy. And as drillers’ targets become smaller or more difficult to land in, shrinking the EOU is paramount to avoiding costly sidetracks or colliding with other wells.