Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Lithology-independent, high-resolution porosity logs

Conference ·
OSTI ID:207269
A unique attribute of nuclear magnetic resonance (NMR) logging is the ability to measure a lithology-independent porosity. New NMR tools have generated renewed interest in measurements related to producibility, such as permeability and definition of water production potential. Industry discussion of those parameters has sometimes overshadowed the value of a lithology-independent porosity measurement. Such a porosity log can be easily understood by and utilized by non-specialists as well as log interpretation experts. The log reflects true porosity even in a complex lithology that changes over the well interval, such as limestone to dolomite transitions with evaporate inclusions. Similarly, since the log reads near zero in compacted shale, the measurement closely approaches effective porosity in clastic environments. A new pad-type NMR logging tool produces such a porosity measurement with excellent vertical resolution. Investigation is focused within a volume whose vertical dimension is only 6 in. Examples from a number of wells illustrate excellent repeatability and resolution of thin reservoir components that are not visible with other NMR devices or conventional porosity logs. Logs are verified by core data and electrical images. The measurement is unaffected by borehole salinity, and the tool is combinable with other wireline tools.
OSTI ID:
207269
Report Number(s):
CONF-951002--
Country of Publication:
United States
Language:
English

Similar Records

Automatic determination of lithology from well logs
Journal Article · Tue Sep 01 00:00:00 EDT 1987 · SPE (Society of Petroleum Engineers) Format. Eval.; (United States) · OSTI ID:5992175

Automatic determination of lithology from well logs
Conference · Sat Sep 01 00:00:00 EDT 1984 · Soc. Pet. Eng. AIME, Pap.; (United States) · OSTI ID:6326778

Determination of lithology from well logs by statistical analysis
Journal Article · Mon Nov 30 23:00:00 EST 1987 · SPE (Society of Petroleum Engineers) Format. Eval.; (United States) · OSTI ID:5537199