NOTE: This item is not available outside the Texas A&M University network. Texas A&M affiliated users who are off campus can access the item through NetID and password authentication or by using TAMU VPN. Non-affiliated individuals should request a copy through their local library's interlibrary loan service.
Design and history matching of a waterflood/miscible CO₂ flood model of a mature field: the Wellman Unit, West Texas
MetadataShow full item record
The Wellman Unit is located in Terry County, West Texas. It is a Wolfcamp massive limestone reef. The reservoir is considered geologically unique due to the double cone-shape structure with a maximum closure of 825 feet above the OWOC. Three stages of depletion occurred over 50 years of production: 1) Primary depletion under a combination of solution gas drive and bottom water drive 2) Secondary recovery was initiated in 1979 via water injection into the flank of the reservoir and 3) CO₂ miscible injection was implemented in three wells on top of the structure in 1983. In this research, production and reservoir data was revised and integrated to develop a full field, 3-D, black oil simulation model. The primary objective was to reproduce via history matching, the historical performance of the reservoir under primary, secondary and tertiary stages of depletion. A secondary objective was developing a calibrated model that can be used to evaluate, design and plan future reservoir management decisions. To accomplish this task, a reservoir model was built that honors the structural configuration of the reservoir. A flexible grid system comprised of 16,767 grid blocks was built based on corner point - non orthogonal geometry. During the matching process, parameters were ranked according to uncertainty. The most uncertain parameter was the transmissibility and physical size of the under-lying aquifer system. Finally, the pseudo-miscible option based on the Todd and Longstaff theory was implemented as a modification to model behavior of the CO₂ miscible flood. The results can be summarized by the following: 1) History matching the primary depletion stage was satisfactory. 2) Extensive aquifer tuning was required to maintain sufficient reservoir pressure for CO₂ injection and match the field data during the waterflooding phase. 3) A complete pressure match was achieved through primary depletion, waterflooding and CO₂ injection, however the match on liquid production rate was compromised in order to tune the final pressure match from 1986-1995. The results of this work provide a foundation for future research into this hydraulically complicated reservoir. Once the complete calibrated model has been built, the simulation can be used to forecast future operations like blow-down or gas storage.
DescriptionDue to the character of the original source materials and the nature of batch digitization, quality control issues may be present in this document. Please report any quality issues you encounter to firstname.lastname@example.org, referencing the URI of the item.
Includes bibliographical references (leaves 180-181).
Issued also on microfiche from Lange Micrographics.
Rojas Barile, Jose Humberto (2002). Design and history matching of a waterflood/miscible CO₂ flood model of a mature field: the Wellman Unit, West Texas. Master's thesis, Texas A&M University. Available electronically from
Request Open Access
This item and its contents are restricted. If this is your thesis or dissertation, you can make it open-access. This will allow all visitors to view the contents of the thesis.