Definition - What does Depth mean?
Generally depth is defined as the distance from the top to the bottom of a surface. It is also referred to as the measurement of the distance to and from the reference points of the well. It is also called depth in a well or the location of oil reservoir. The distance or depth is not essentially measured in a vertical direction of a well.
Petropedia explains Depth
In the oil industry, depth is a term that is usually referred to location underneath or the distance from a point of elevation for a well. There is another term that is used for it, depth in a well. Either ways, the term depth is used to measure the distance of the well from the top to bottom. However, because a well may not always be present in a vertical position, the term depth can vary for every wellbore. There are several different forms of depths such as true vertical depth, measured depth, driller’s depth etc.