Topic:
Markers and the significance of marker indexed as MD, TVD or TIME.

Description:
 

Solution:
Markers interpreted along the well bore can have a marker index as measured
depth (MD), true vertical depth (TVD) or TIME.

Significance of marker with marker index of TIME: The marker will not change
position in TIME with change in time/depth DVT or any change in datum elevation.

Significance of marker with marker index of TVD: The marker will change position
with change in datum elevation and change in the time/depth DVT.  Changes in
deviation survey will not affect the time position of the marker but will
affect the depth position.

Significance of marker with marker index of MD: The marker is tied to the
borehole and will change position with any change in the borehole. This will be
affected by datum elevation, time/depth DVT as well as deviation survey changes.




Last Modified on: 04-DEC-98