Tvd:

True vertical depth.

Terms Related to Tvd

• True vertical depth

  The vertical depth (tvd) from the surface to the depth of interest. Used for formation comparison and calculation of hydraulic pressures.

• Normal pressure gradient

  The normal pressure divided by true vertical depth.

• Equivalent circulating density (ecd)

  The increase in bottomhole pressure expressed as an increase in pressure that occurs only when mud is being circulated. Because of friction in the annulus ...

• Deviation

  Departure of the wellbore from the vertical, measured by the horizontal distance from the rotary table to the target. The amount of deviation is a ...

• Perforation depth control log (pdc log)

  A special type of nuclear log that measures the depth of each casing collar. Knowing the depth of the collars makes it easy to determine ...

• Driller’s depth

  The depth of a well or features within the wellbore as measured while drilling. The measured length of each joint of drillpipe or tubing is added ...

• Depth reference

  The point in a well from which depth is measured. Alternatively, the depth reference is the point at which the depth is defined as being ...