Patent ID: 8214151
Filing Date: 2012-07-03
Classification: G01V

Abstract:
1. For use in a subterranean formation traversed by a borehole, a method of determining the presence of a high thermal neutron capture cross section-containing proppant in the formation, the method comprising the steps of: moving a logging tool through a length of the borehole along the formation, the logging tool having (1) a neutron emitting source, (2) a plurality of thermal neutron or capture gamma ray logging detectors located at different distances from the neutron source, and, during operation of the logging tool, generating (3) a plurality of detector count rates, and (4) a detector count rate ratio of two of the detector count rates; establishing a first predetermined relationship between a detector count rate and a hydrogen index of the formation without proppant therein, establishing a second predetermined relationship between the detector count rate ratio and a hydrogen index of the formation without proppant therein; utilizing the first predetermined relationship and detector count rates to generate computed first apparent hydrogen index values along the length of the logged formation; utilizing the second predetermined relationship and detector count rate ratios to generate computed second apparent hydrogen index values along the length of the logged formation; and comparing the computed first and second apparent hydrogen index values to identify differentials therein indicative of the presence of proppant in the formation.