Abstract: In some embodiments, apparatus and systems, as well as methods, may operate to acquire signature data representing a plurality of nuclear magnetic resonance (NMR) echo trains associated with a material comprising a first fluid and a second fluid, force a subset of the signature data associated with the first fluid or the second fluid to correspond to single-peak signatures in the T1 and/or T2 domains, and solve for the first fluid and second fluid saturation. The first fluid may include oil, gas, or water and the second fluid may include oil-based mud filtrate or water-based mud filtrate, among others.

Abstract: In some embodiments, apparatus and systems, as well as methods, may operate to acquire data representing a plurality of nuclear magnetic resonance (NMR) echo trains associated with a material, such as a geological formation. Additional operations may include inverting a model of at least one of the plurality of NMR echo trains to provide an estimated distribution of transverse relaxation time constants, inverting models of selected ones of the plurality of NMR echo trains using the estimated distribution of transverse relaxation time constants to provide an estimated diffusion distribution, and inverting a model of selected ones of the plurality of NMR echo trains, using the estimated distributions of transverse relaxation time constants and diffusion, to provide an apparent and an intrinsic probability density function to identify fluid types in the material.

Abstract: In some embodiments, apparatus and systems, as well as methods, may operate to acquire signature data representing a plurality of nuclear magnetic resonance (NMR) echo trains associated with a material comprising a first fluid and a second fluid, force a subset of the signature data associated with the first fluid or the second fluid to correspond to single-peak signatures in the T1 and/or T2 domains, and solve for the first fluid and second fluid saturation. The first fluid may include oil, gas, or water and the second fluid may include oil-based mud filtrate or water-based mud filtrate, among others.

Abstract: In some embodiments, apparatus and systems, as well as methods, may operate to acquire fluid signature data representing a plurality of nuclear magnetic resonance echo trains associated with fluids in a material, to simultaneously invert a plurality of relaxation time models to provide inverted results, and to determine fluid properties using the inverted results. The relaxation time models may be associated with the fluids using the fluid signature data after constraining ratios of T1 relaxation times to T2 relaxation times.

Abstract: In some embodiments, apparatus and systems, as well as methods, may operate to acquire data representing a plurality of nuclear magnetic resonance (NMR) echo trains associated with a material, such as a geological formation. Additional operations may include inverting a model of at least one of the plurality of NMR echo trains to provide an estimated distribution of transverse relaxation time constants, inverting models of selected ones of the plurality of NMR echo trains using the estimated distribution of transverse relaxation time constants to provide an estimated diffusion distribution, and inverting a model of selected ones of the plurality of NMR echo trains, using the estimated distributions of transverse relaxation time constants and diffusion, to provide an apparent and an intrinsic probability density function to identify fluid types in the material.