Fluid contact monitoring in some western Canadian reefs
Thirty years have passed since oil was first discovered in reefal reservoirs in the Western Canadian Sedimentary Basin. The early giants such as Redwater, Leduc, and the large Swan Hill pools have been followed in subsequent years by the development of reef pools of declining size, culminating with the discovery of the Keg River reefs of the Rainbow Zama area some 10 years ago. Unfortunately the majority of reef pools are reaching a mature stage in their productive cycle. With this maturity comes an increasing need for the log analyst to diversify his role from merely recognizing hydrocarbons during the discovery process, to the analysis of remaining hydrocarbon distribution within the depleting reservoir. The monitoring of fluid movement has become an integral part of reservoir description. Geologist, log analyst, reservoir and production engineer must work as a coordinated team to explain the often anomalous fluid distributions that occur in the well bore. Oil recovery from the Devonian Leduc age reef at Golden Spike, Alberta has been, until recently, by displacement with a miscible solvent bank. The monitoring of gas--fluid interfaces has been accomplished by the use of pulsed neutron logs in cased holes and the combination of SNP-Density and SNP-Acoustic data in open hole situations. At Judy Creek premature advances of formation water and inefficient reservoir depletion resulted from a highly stratified reefal reservoir. Pulsed neutron logs, used after the recognition of the production problems, have helped define oil-water distributions in the reservoir and led to an improvement in recovery efficiency. Rainbow Devonian Keg River reefs are subjected to gas, miscible and water injection recovery schemes. A pool that has been converted from a primary gas expansion drive to water drive by injection has used the pulsed neutron log to monitor the effectiveness of this change.
- OSTI ID:
- 6771629
- Journal Information:
- Log Anal.; (United States), Journal Name: Log Anal.; (United States) Vol. 19:2; ISSN LGALA
- Country of Publication:
- United States
- Language:
- English
Similar Records
Refined reservoir description to maximize oil recovery
Middle Devonian reefs of the Rainbow region of Northwestern Canada--exploration and exploitation
Related Subjects
020300* -- Petroleum-- Drilling & Production
440105 -- Radiation Instrumentation-- Radiometric Instruments-- (-1987)
440400 -- Well Logging Instrumentation
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
47 OTHER INSTRUMENTATION
CANADA
DATA ANALYSIS
ENGINEERING
ENHANCED RECOVERY
FLUID INJECTION
IRRADIATION
MONITORING
NEUTRON LOGGING
NEUTRON-NEUTRON LOGGING
NORTH AMERICA
OIL WELLS
PULSED IRRADIATION
RADIOACTIVITY LOGGING
RESERVOIR ENGINEERING
WATERFLOODING
WELL LOGGING
WELLS