1. n. [Reservoir Characterization, Formation Evaluation]

A phenomenon by which a nucleus absorbs electromagnetic radiation of a specific frequency in the presence of a strong magnetic field. Isidor Isaac Rabi (1898 to 1988), an American physicist born in Austria, first detected magnetic resonance in 1938. Since then, magnetic resonance has been applied to the detection of light atoms (such as hydrogen in hydrocarbons) and as a nondestructive way to study the human body.

Alternate Form: NMR,  nuclear magnetic resonance measurement