Qualitative Rock Mechanical Characterization from Advanced Mud Logging XRF-Derived Mineralogy

This study presents a novel workflow designed to address these challenges by enabling comprehensive formation evaluation and borehole geomechanical modeling through X-ray fluorescence (XRF) analysis of mudlog cuttings. From the XRF- obtained mineralogy, intrinsic rock properties including dominant mineral constituents, matrix density (calculated from constituents densities), and a brittleness index (derived from brittle and ductile mineral content) are determined. Furthermore, compressional (DTC) and shear (DTS) wave slowness curves, alongside key mechanical properties such as Unconfined Compressive Strength (UCS), Poisson’s ratio (ν), and Young’s modulus (E), are systematically derived.

An example will be discussed from an application in Kuwait demonstrating how Qualitative Geomechanical characterization from cutting’s XRF is a very valuable formation evaluation workflow in long horizontal wells where acoustic logging and traditional rock mechanical characterization is cost prohibited. Qualitative geomechanical properties such as Young’s modulus, Poisson’s ratio, and unconfined compressive strength as used to optimize horizontal multi-stage stimulation treatments and perforation’s cluster location along the wellbore completion design.