Nuclear magnetic resonance method and apparatus for remote detection and volumetric measurement of petroleum reserves.

摘要

The nucleons chemically bound in water and oil present in formation are preferentially aligned in the earth's magnetic field causing natural nuclear paramagnetism within the formation. This paramagnetism causes a slight alteration in the strength of the earth's magnetic field in the vicinity of a borehole adjacent to the formation. Repeated application of an A.C. magnetic field at the Larmor frequency of the nucleons present yields an amplitude modulation of the earth's magnetic field. The magnitude of such modulation yields the total number of nucleons present and the phase contains information used to provide information regarding oil and water present in the formation.