When a [[Normal hydrostatic pressure#Fluid pressure|fluid pressure]] is higher than estimated from the [[Normal hydrostatic pressure gradients|normal hydrostatic fluid gradient]] for a given depth, it is called overpressure. For this situation to occur, the fluid must first be trapped within a rock unit (pressure compartment). | When a [[Normal hydrostatic pressure#Fluid pressure|fluid pressure]] is higher than estimated from the [[Normal hydrostatic pressure gradients|normal hydrostatic fluid gradient]] for a given depth, it is called overpressure. For this situation to occur, the fluid must first be trapped within a rock unit (pressure compartment). |