Formation pressure equal to the pressure exerted by a vertical column of water with salinity normal for the geographic area.
Source: API RP 59, Recommended Practice for Well Control Operations, Second Edition, May 2006. Global Standards
“Normal pressure” means a formation pore pressure, proportional to depth, which is roughly equal to the hydrostatic pressure gradient of a column of salt water (.465 psi/ft).
Source: Corporation Commission, Oil and Gas Conservation, Oklahoma Administrative Code 165:10, February 2013. Regulations