... In the frequency range of this study, 1-300 MHz, the dominant relaxation mechanism encompasses interfacial polarization, where the restricted charge movement in complex structures adds to the dielectric storage through a structure-dependent polarization process. These complex systems exhibit...

...., spherical shape, with a smooth surface ( Brownstein and Tarr, 1979 ). However, the solid-pore interface is irregular and full of roughness ( Chen et al., 2007 ). The irregularity and roughness increase the surface area, accelerate NMR relaxation and result into smaller T 2 values. Without accounting...

...) stress-shadow relaxation around the monitor well fracture as fluid leaks-off from the nearby treatment well fracture into the formation. We present a new method to estimate the permeability of the stimulated region around the created fractures. We show that, along with the permeability of the SRV region...

.... The results show that the relaxation of the generated kerogen matrix after the deletion of dummy atoms should be part of the process. Without the relaxation, the pore volume will be overestimated significantly. The transport diffusivity in flexible kerogen matrix is generally higher than in rigid kerogen...

... on magnetization decay can be ignored ( Mohnke and Klistzch 2010 ). Brownstein and Tarr (1979) proposed the mixed boundary condition that governs the decay of spins on the boundary surfaces of porous media and introduced the theoretical basis for surface relaxation. The exact formulation of the boundary...

... strength – up to 15,000 psi (1034 bar) – and elasticity (>6%). When compared to elastomers, ECC generates much higher sealing and anti-extrusion forces, and shows significantly less or no stress relaxation at high temperatures. In addition, the low density and self-lubricating property observed from...

...) to estimate wettability has been predicated on the earlier recognition of the enhanced surface relaxation of wetting fluids,( Fatt et al. 1956 ). An approach that acquires the formation MR signal, and then extracts a fluid sample for bulk fluid MR measurement to decouple the formation's apparent T 2...

... Optimization (PSO, a global search technique), a PSO-MADS hybrid and Branch and Bound (B&B, a rigorous search procedure that requires relaxation of the categorical variables). Two example cases involving channelized reservoir models are presented. The PSO-MADS hybrid is shown to outperform the standalone...

... Abstract NMR relaxation measurements are routinely used in the petroleum industry to estimate permeability and to partition fluids to estimate irreducible water saturation. The shape of the relaxation time distribution is controlled by many mechanisms like pore-coupling in the presence...

... Abstract The Nuclear Magnetic Resonance (NMR) response of gas in gas shale nanopores is different from that of bulk gas, where relaxation is dominated by spin rotation and diffusion is unrestricted. Gas shales are characterized by very low porosity and ultra low permeabilities. Their porosity...

... measurement to determine the fluid levels was developed using differential thermal relaxation. Cold water was pumped around a U tube containing an optic fiber and clamped outside the perforated tubing across the open hole until the temperature at the reservoir depth inside this U tube was considerably less...

.... By analogy to the electrical conductors, permeability represents the reciprocal of the resistance that the porous medium offers to the fluid flow ( Daniel and Bass, 1987 ). Introduction relaxation porosity equation upstream oil & gas flow in porous media permeability hydrocarbon saturation...

... For these reasons, alternative methods for saturation determination in carbonates are being sought. One candidate is nuclear magnetic resonance (NMR) due to its sensitivity to the fluids inside the formation. In some cases, a simple relaxation (T1 or T2) distribution is sufficient to separate...

... and management. log analysis Modeling & Simulation Upstream Oil & Gas application rock type plug pore size distribution borehole NMR entry pressure saturation well logging pressure curve carbonate reservoir relaxation capillary pressure curve capillary pressure drainage capillary...

..., and indicate that NMR has great potential as a tool for in-situ viscosity determination. nmr spectrum viscosity prediction viscosity model relaxation crude oil emulsion oil viscosity droplet size emulsion viscosity bitumen spe 77329 viscosity upstream oil & gas log analysis heavy oil...

... because of surface relaxation of the wetting phase fluid. The surface relaxation rate, however, must be significant compared to the bulk relaxation rate in order for wettability to noticeably affect the NMR response. We present results showing that the surface relaxation rate at lower wetting phase...

... permeability permeability correlation nmr permeability correlation numerical simulation relaxation sandstone microstructure formation factor reconstruction porosity gradient correlation micro-ct image flow in porous media simulation fluid dynamics fontainebleau sandstone...

... pore structure magnetization pore size uncoupled pore structure relaxation algorithm multiphase fluid saturation log analysis simulation result geometry simulation well logging saturation magnetic field gradient carbonate rock fluid saturation spe 77399 simulation algorithm...

... methods. porosity permeability model pore amplitude fraction relaxation upstream oil & gas permeability characterization evaluation low field nmr well logging fraction reservoir carbonate secondary porosity fraction application spe 77401 log analysis correlation carbonate...

... on the permeability calculation. In field practice, a T2 cut-off of 100 msec is used for carbonate reservoirs. In general, the oil bulk relaxation falls in the free fluid area. However, for 28 cp oil viscosity, the bulk relaxation time for the oil is around 40 to 60 msec. This means that the oil signature is coming...