The foundation for multiwell geologic models, core description produces stratigraphic and geologic information used for interpretation of depositional environments, diagenetic transformations, and fracture identification. This information provides a framework for linking other measurements and developing scaling relationships for petrologic evaluation.
X-ray diffraction (XRD)
Semiquantitative bulk and clay XRD determines mineralogy, clay type, and clay abundance. Results are reported as bulk mineralogy and clay-weight percent, individual clay species, and percent expandability. These data are vital to diagenetic studies, facies analysis, log calibration, and prediction of fluid sensitivity. Measurements are critical for the proper evaluation of shale plays.
Fourier transform infrared spectroscopy (FTIR)
FTIR provides the bulk mineralogy and concentrations of both crystalline materials and amorphous phases in rocks and other solid phases. Dual-range FTIR (merged mid-infrared and far-infrared spectra) is especially useful in distinguishing between different types of hydroxyl and hydrous phases, opaline and paracrystalline silica phases, order of kaolinite clays, and micas versus illite clays.