دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: (am) modulation of the amplitude of a radio carrier wave in accordance with the strength of the audio or other signal. amplitudes n pi: shapes and heights of the peaks in a spontaneous potential curve.

n: finely crystalline, generally lightcoloured extrusive igneous rock com- posed largely of plagioclase feldspar with smaller amounts of dark-coloured minerals. Compare diorite.

n: sandstone composed largely of feldspar grains and deriving from granitic source rocks.

A sandstone containing 25% or more of feldspar, usually derived from igneous rock.

n: the average of all the instantaneous values of current or voltage in one-half a cycle of AC electricity;equal to 0.636 times the maximum value.

n: an extrusive igneous rock that is dense, fine grained, and often dark gray to black. Compare gabbro.

the most common volcanic rock. Usually fine grained.

n: igneous or metamorphic rock, which seldom contains petroleum. Ordinarily, it lies below sedimentary rock. When it is encountered in drilling, the well is usually abandoned.

unproductive rocks, usually igneous or metamorphic, at the bottom of a sedimentary rock sequence.

an irregular intrusion of an igneous rock into another rock.

the simultaneous flow of two immiscible fluids.

n: a substance of dark to black colour consisting almost entirely of carbon and hydrogen with very little oxygen, nitrogen, or sulphur. Bitumens occur naturally and can also be obtained by chemical decomposition.

pyrogeneous, essentially non reactive, hydrocarbon. Most bitumen is not considered as movable through the reservoir under normal conditions of flow unless heated.