A Practical Approach to Determine Permeability from Wireline Measurements

Abstract

Permeability is a crucial input to any simulation effort to forecast production. It is available from different sources: core, nuclear magnetic resonance (NMR), wireline formation tester (WFT) and drill stem test (DST). These sources are different in many aspects: the type of permeability they measure, e.g. absolute or effective, the scale of measurement in the vertical and the lateral directions and the degree of inconvenience caused by the data acquisition process in terms of operational constraints, costs, safety issues, etc.Much effort has been invested by the industry to be able to use the most cost effective tools, NMR and WFT, for permeability measurement as substitute for the less convenient ones: core and DST. Results of these efforts are still mostly qualitative.This work is a summary of the senior author's MSc thesis 1 which reviewed the different sources of permeability and their limitations using field data from, an oil bearing, clastic reservoir that included core, NMR, WFT and DST. All these data were analyzed and interpreted for permeability evaluation. The objective of the study was to develop an approach for calibrating the static NMR permeability log with the WFT dynamic data and to compare the results with the traditional approach of calibrating with cores. Permeabilities from both approaches were upscaled for comparing with DSTderived permeabilities.It was found that the upscaled WFT-calibrated NMR permeabilities match the DST permeabilities as satisfactorily as the upscaled core-calibrated NMR permeabilities.

Impacto de los Métodos Aplicados para la Determinación de la Permeabilidad y su Influencia en el Gerenciamiento del Reservorio en el Campo Shushufindi

“…Los datos de permeabilidad de núcleos son obtenidos de varios pozos, a medida que se perfora la zona de interés, estas constituyen una pequeña muestra en comparación al tamaño del yacimiento, es una manera directa de medir la permeabilidad de un medio poroso, esto independientemente del volumen de la muestra en relación al yacimiento en análisis (Al-Harbi et al, 2007).…”

“…Ninguno de los métodos disponibles para determinar la permeabilidad, sean estos análisis de núcleos, registros eléctricos, probadores de formación con cable, pruebas de pozos, y análisis transiente de producción, pueden trabajar individualmente (Al-Harbi et al, 2007).…”

In situ recovery, an alternative to conventional methods of mining: Exploration, resource estimation, environmental issues, project evaluation and economics

“…new wireline tools such as nuclear magnetic resonance (NMR) logging provides a means of direct measurement of in situ permeability, as well as clay:sand ratios and porosity (Harbi et al, 2007). A scoping study or preliminary economical assessment is an early stage evaluation of a mining project.…”