Introduction to Gyro Surveys
Gyro surveys will be taken when the casing has been run if it was not possible to perform an MMS in the open hole. There are two distinct groups of slim, surface reading, gyro surveying tools:
- those that require orientation to a foresight reference bearing on the surface (‘surface referenced’) and,
- those that seek True North.
Gyro Single Shots (GSS) surveys shall be used in place of magnetic based instruments where magnetic interference is suspected.
A GMS survey shall be taken whenever MMS surveys have . . .