Changes

==Fluids==

==Fluids==

A fluid is “a substance (as a liquid or gas) tending to flow or conform to the outline of its container” (Webster, 1991). Thus, the explorationist should think of oil, gas, and water as fluids to understand their behavior in the subsurface. In this chapter, where the fluid state (liquid or gaseous) is important, the state (or phase) is specified.

A fluid is “a substance (as a liquid or gas) tending to flow or conform to the outline of its container.”<ref name=Webster_1979>Webster's New Twentieth Century Dictionary, Unabridged, 2nd ed., 1979: New York, Simon and Schuster, 2129 p.</ref> Thus, the explorationist should think of oil, gas, and water as fluids to understand their behavior in the subsurface. In this article, where the fluid state (liquid or gaseous) is important, the state (or phase) is specified.

==Fluid pressure==

==Fluid pressure==

==Properties of hydrostatic pressure==

==Properties of hydrostatic pressure==

Normal hydrostatic pressure has the following properties:<ref name=ch05r5>Dahlberg, E., C., 1994, Applied Hydrodynamics in Petroleum Exploration, 2nd ed.: New York, Springer-Verlag, 295 p. Excellent subsurface fluid pressure reference. Covers hydrodynamic and static fluids.</ref>

Normal hydrostatic pressure has the following properties:<ref name=ch05r5>Dahlberg, E., C., 1994, Applied Hydrodynamics in Petroleum Exploration, 2nd ed.: New York, Springer-Verlag, 295 p.</ref>

* Amount of pressure increases with depth.

* Amount of pressure increases with depth.

==See also==

==See also==

* [[Geostatic and lithostatic pressure]]

* [[Geostatic and lithostatic pressure]]

* [[Normal hydrostatic pressure gradients]]

* [[Normal hydrostatic pressure gradients]]