Page 369 - Geology and Geochemistry of Oil and Gas

330 APPENDIX C

Pressure head The height (h) of a column of liquid supported by
pressure at a point in a liquid: h ¼ p/g, where h is the
head of liquid (e.g., in ft), p is the pressure (e.g., in lb/
2
ft ), and g is the specific weight of liquid (e.g., in lb/
3
ft ). Syn: Hydrostatic head.
Pressure log Measurement of the formation pressure at various
depths.
Pressure solution Process in which carbonate dissolution occurs at
burial as a result of increased pressure due to
overburden stress; usually results in the formation of
stylolites and interpenetrative grain contacts. Syn:
Pressure dissolution.
Primary cementing The cementing operation that takes place immediately
after the casing has been run into the hole.
Primary recovery The production obtained using the initial reservoir
energy.
Probability [stat] A statistical measure of the likelihood of occurrence
of an event.
Production log Measurement of production status of a completed
well. Yields information on the nature and movement
of fluids within the well.
Production test A test of the well’s producing potential usually done
during the initial completion phase.
Productivity index It is equal to PI ¼ q/( p r p wf ), where q is the flow rate
(e.g., bbl/d); p r is the average reservoir pressure (e.g.,
psia); and p wf is the flowing bottom-hole pressure at
the wellbore (psia).
Progradation The seaward accretion and migration of sedimentary
bodies and corresponding depositional environments.
Cf: Regression [sed].
Protodolomite Term used in reference to dolomite that is poorly
ordered and compositionally impure (i.e., calcic).
Provenance The source or place of origin of detrital sediments.
Pseudospar Fabric of carbonate crystals, resulting from
recrystallization of micrite-size crystals or grains, that
are larger than 30 mm in size.
Pumping Lifting fluids from the production well to the surface
by an artificial lift method.
Pumping off Pumping the reservoir fluids out of the well faster
than they can enter the wellbore.
PVT analysis An examination of reservoir fluid in a laboratory
under various pressures, volumes, and temperatures
to determine the characteristics and behavior of the
fluid.