QA/QC of gamma-gamma geophysical well logging data applied to the characterization of high density rock masses

Abstract

This paper proposes a set of procedures for quality control of gamma-gamma geophysical well logging data applied to the study of high density rock masses, which: (1) linearity verification between different spaced gamma-gamma sensors; (2) verification of the recorded densities range; (3) comparison between the internal diameters of the borehole walls and the nominal drilling diameter; and (4) verification of the proportionality between the densities measured by the sensors of short and long spacing by means of residual analysis. The quality control allows to mitigate any omissions of data interpretation (human factor), and to minimize the computational time, as well as facilitate any changes to the quality control criteria.