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compatible scales

1. n. [Formation Evaluation]
Scales for different logs that are chosen so that the logs will overlay in certain conditions. For example, a sandstone-compatible scale may have the neutron log scaled from 0.45 to -0.15 vol/vol and the density from 1.9 to 2.9 g/cm3. Then, in a pure quartz sandstone filled with fresh water, the two logs will overlay as the porosity varies.