1. vt. [Geology]

To seek a comparison or equivalence. Scientists attempt to compare or match up well log signatures, chemical signatures, seismic signatures, fossils and rock samples across wide areas to determine the equivalence, extent, thickness, quality, relative age or other properties of stratigraphic units and rock bodies.

Alternate Form: correlation

See: check-shot survey,  chronostratigraphy,  lithostratigraphy,  marker bed,  pick,  signature,  stratigraphy,  stratum,  tie,  two-dimensional survey

2. vb. [Production Logging, Well Completions, Formation Evaluation, Reservoir Characterization]

To compare and fix measured depths with known features on baseline logs of the wellbore tubulars and the surrounding formation.

Synonyms: depth correlation