Using Images in Real-Time Interpretation

Ultra high-resolution logging-while-drilling (LWD) resistivity images successfully identified fracture zones in real time while drilling heavily fractured and complexity heterogeneous carbonate formations in Well “X”. Geological interpretation of the high-resolution resistivity images revealed the presence of a few major conductive fractures that were possibly enhanced by drilling and a large number of partial, discontinuous conductive and resistive fractures. The identification of zones contributing to drilling-mud losses allowed timely design of a completion plan to effectively isolate the fractured zones and select perforation locations away from the open fractures. With the added capability to collect data from different depths of investigation, the subsequent analysis of fluid invasion provided input data for petrophysical formation evaluation and helped to differentiate near-wellbore features deep in the formation. Following drilling of the well, geological interpretation of the recorded log data, which provides better sampling and data density, identified and characterized borehole structural features such as structural dip of intersected bed boundaries, fracture type (conductive, resistive), fracture morphology and geometry (continuous, discontinuous), and fracture density and distribution along the logged interval. Images also provided identification of minor faults.