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  | isbn    = 0-89181-602-X

  | isbn    = 0-89181-602-X

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A critical element in detecting the presence of hydrocarbons using [[formation fluid pressure]]s is an accurate hydrostatic pressure gradient for zones of interest. We use the hydrostatic pressure gradient to determine the expected pressures for the zone of interest as if it had no hydrocarbons. Pressures exceeding hydrostatic pressures may be due to the presence of a [[hydrocarbon column]]. Most methods for determining hydrostatic pressures are not very precise. Other petrophysical data can help when the estimated hydrostatic pressure gradient is suspect.

A critical element in detecting the presence of hydrocarbons using formation fluid pressures is an accurate hydrostatic pressure gradient for zones of interest. We use the hydrostatic pressure gradient to determine the expected pressures for the zone of interest as if it had no hydrocarbons. Pressures exceeding hydrostatic pressures may be due to the presence of a [[hydrocarbon column]]. Most methods for determining hydrostatic pressures are not very precise. Other petrophysical data can help when the estimated hydrostatic pressure gradient is suspect.

The goal of constructing a hydrostatic pressure–depth plot is to identify pressures greater than the hydrostatic gradient that may correspond to a hydrocarbon-bearing zone. A hydrostatic pressure–depth plot can be constructed from any of the following:

The goal of constructing a hydrostatic pressure–depth plot is to identify pressures greater than the hydrostatic gradient that may correspond to a hydrocarbon-bearing zone. A hydrostatic pressure–depth plot can be constructed from any of the following: