Survey Tool BGS integration

Description

Well Seeker Pro version 2.2.0.0 includes an integration with the British Geological Survey’s Global Geomagnetic Model (BGGM). This integration allows for real time updates to some of the values in the selected magnetic survey tools Instrument Performance Models (IPM’s). This in turn results in greater accuracy when calculating the ellipse of uncertainty for wellbores and plans. This technical note details how this integration works.

Activation

To activate the BGGM integration, open the Tools menu and select Survey Tool Editor. Within the Survey Tool Editor window, toggle on the option Use BGGM error estimates.

Note that the integration requires an internet connection to function.

Function

The BBGM integration affects the following magnetic error terms:

• DECG: MWD – Declination – Global (degrees)

• DECR: MWD – Declination - Random (degrees)

• DBHG: MWD – BH-Dependent Declination – Global

• DBHR: MWD – BH-Dependent Declination – Random

• MDIG: MWD – Magnetic Dip with Z-Axis Correction – Global (degrees)

• MDIR: MWD – Magnetic Dip with Z-Axis Correction – Random (degrees)

• MFIG: MWD – Total Magnetic Field with Z-Axis Correction – Global (nT)

• MFIR: MWD – Total Magnetic Field with Z-Axis Correction – Random (nT)

Note: If the selected IPM does not contain any of the above error terms, then this feature will not have any effect on the calculations.

When the BGGM integration is turned OFF, the values for these terms are fixed based on the selected survey tool:

When the BGGM integration is turned ON, any time Well Seeker generates an error ellipse or performs an anti-collision scan, Well Seeker will retrieve the time and location specific values for these terms from the BGS BGGM High Definition (degree 1440) model with associated ISCWSA Rev 4 model-specific uncertainties. These values are then used in place of the fixed values that are defined in the selected IPM.

Note that the values in the IPM will never physically be changed when this integration is switched on. The BGGM values are used behind the scenes and the user will not see these.