Charles Flaum

Diffusion-relaxation distribution functions of sedimentary rocks in different saturation states

We present diffusion-relaxation distribution functions measured on four rock cores that were prepared in a succession of different saturation states of brine and crude oil. The measurements were performed in a static gradient field at a Larmor frequency of 1.76 MHz. The diffusion-relaxation distribution functions clearly separate the contributions from the two fluid phases. The results can be used to identify the wetting and non-wetting phase, to infer fluid properties of the phases, and to obtain additional information on the geometrical arrangement of the phases. We also observe effects due to restricted diffusion and susceptibility induced internal gradients.

Geologically Consistent Resolution Enhancement of Petrophysical Analysis With Image Log Data

Very thin, laminated sand-shale sequences pose a challenge to petrophysical evaluation. The poor vertical resolution of the log measurements results in pessimistic estimates of hydrocarbon volumes and producibility. An earlier proposal by Flaum to enhance the resolution of the analysis using a high-resolution clay indicator did not account for variations in clay mineralogy and porosity with clay content. We present here a technique to incorporate results of core mineralogy measurements to ensure a geologically consistent resolution enhancement of the petrophysical analysis and we compare the results in an actual field example.