The application of induced gamma-ray spectroscopy measurements: characterisation of a North Sea reservoir

Implementation of a correct mineral transform model and strategy on elemental chemistry, derived from gamma-ray spectroscopy logging tools, can provide a continuous accurate measurement of mineralogy through a complete reservoir section. A set of reservoir cores from the North Sea (Brent Group) is used to evaluate various models developed for transforming elemental data into geologically meaningful mineralogy. Emphasis is placed on evaluating transform techniques using well-constrained laboratory data before applying the models to elemental data derived from nuclear logging tools. This evaluation procedure aims to determine the most suitable transform model, as well as to quantify some of the inherent problems with mineral inversion. Strategies for overcoming such problems are also addressed