Well Control - Hydrostatic Pressure

Hydrostatic Pressure

Hydro means water, or fluid, that exerts pressure and static means not moving or at rest. Therefore, hydrostatic pressure is the total fluid pressure created by the weight of a column of fluid, acting on any given point in a well.In oil and gas operations, It is represented mathematically as; Hydrostatic pressure = pressure gradient × true vertical depth or Hydrostatic pressure = fluid density × conversion factor × true vertical depth .

The figure shows two wells, well X and Y. Well X has measured depth of 9800 ft and a true vertical depth of 9800 ft while well Y has measured depth of 10380 ft and its true vertical depth is 9800 ft.To calculate the hydrostatic pressure of the bottomhole, the true vertical depth is used because gravity acts (pulls) vertically down the hole. The figure also illustrates the difference between true vertical depth (TVD) and measured depth (MD).