Chapter 3A: Petrophysics

The term “petrophysics” was coined by G.E. Archie and J.H.M.A. Thomeer in a quiet bistro in The Hague. ¹  By their definition, petrophysics is the study of the physical and chemical properties of rocks and their contained fluids. It emphasizes those properties relating to the pore system and its fluid distribution and flow characteristics. These properties and their relationships are used to identify and evaluate hydrocarbon reservoirs, hydrocarbon sources, seals, and aquifers.

The petrophysicist or petrophysical engineer practices the science of petrophysics as a member of the reservoir management team (RMT). (See the chapter on reservoir management in this section of the Handbook .) The petrophysicist provides answer products needed and used by team members, as well as physical and chemical insights needed by other teammates. The reservoir and fluid characteristics to be determined are thickness (bed boundaries), lithology (rock type), porosity, fluid saturations and pressures, fluid identification and characterization, permeability (absolute), and fractional flow (oil, gas, water).