http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Inversion of field-scale partitioning tracer response for characterizing oil saturation distribution
xvi, 153 leaves : illustrations ; 28 cm.
Identifying distribution of remaining oil in the reservoir is vital for evaluation of existing waterflood, design of tertiary recovery projects, and location of infill drilling candidates. In recent years, partitioning interwell tracer tests (PITT) have gained increasing popularity as a means to characterize in-situ distribution of remaining oil. In this thesis, we show an application of an efficient streamline-based inversion technique to the analysis of the PITT data to estimate spatial distribution of remaining oil saturation in the reservoir. During PITT, a conservative and a partitioning tracer are injected into the reservoir. The conservative tracer travels only within the water phase, while the partitioning tracer gets partially absorbed into the oil phase during injection which leads to separation in the tracer responses that can be used to infer remaining oil distribution in the tracer-swept area. Our inversion method relies on analytic computation of the sensitivity of the tracer response to reservoir parameters such as porosity, permeability, and saturation in a single streamline simulation. We follow a two step procedure for PITT analysis in which we first match the conservative tracer response to determine the permeability distribution and then match the partitioning tracer to obtain oil saturation distribution in the reservoir. We first applied the streamline-based inversion method to a synthetic example and then to a large multi-well multi-tracer tracer injection study in McClesky sandstone, Ranger Field, Texas to characterize remaining oil saturation distribution in the reservoir. During the Ranger Field PITT, five conservative and two partitioning tracers were injected in a 320-acre study area through four injection wells and recovered through 13 production wells. We first determined the permeability distribution in the field by matching conservative tracer responses and then matched partitioning tracer responses to determine oil saturation distribution. The results of our work agree well with the analytic method of analysis of PITT also discussed in the thesis. We also show that our results favorably compare with the results of the previous efforts to analyze this PITT by other authors.
Issued also on microfiche from Lange Micrographics.
Includes bibliographical references (leaves 128-130).