Evaluate cement with radioactive tracers, directional gamma ray logs

Journal Article · Mon Jul 01 04:00:00 EDT 1996 · Petroleum Engineer International

OSTI ID:390321

Use of radioactive tracers to evaluate hydraulic fractures has recently been extended through the use of directional gamma ray measurements. The directional gamma ray logging tool determines the azimuthal direction of gamma rays from radioactive isotope-tagged fracture proppants to estimate the fracture direction in well-controlled circumstances. The technology also provides new ways of evaluating primary and squeeze cement jobs by enhancing information from directional gamma ray data with advanced image processing techniques. By tagging the cement with a uniform quantity per unit volume of radioactivity, different levels of gamma ray log response must be attributed to variances in cement quality. Cement evaluation with tracers can help detect: thin cement sheaths; light-weight or low compressive strength cements where the acoustic impedance is near that of water; gas cut cement where the acoustic signal is attenuated; wells with microannulus that cannot be pressured to obtain valid log data; poor casing centralization; and multiple cement stage placement. The paper describes the logging tool, operational procedures, and a log example.

• OSTI ID: 390321
• Journal Information: Petroleum Engineer International, Journal Name: Petroleum Engineer International Journal Issue: 7SUP Vol. 69; ISSN 0164-8322; ISSN PEEID4
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
ANTIMONY 124
CEMENTING
CEMENTS
DESIGN
GAMMA LOGGING
GOLD 198
IODINE 131
IRIDIUM 192
MONITORING
OIL WELLS
OPERATION
QUALITY CONTROL
SCANDIUM 46
TRACER TECHNIQUES
WELL COMPLETION
WELL LOGGING EQUIPMENT