Geosteering Driven by Geophysics – Reservoir Structure Prediction Ahead of Bit

LWD tools measure behind the bit and consequently have several operational limitations: For instance, in horizontal wells, the geological structure can be projected ahead but assuming a constant dip trend. Such constraints can impact the drilling operations for Well Placement applications in complex environments. Therefore, Schlumberger Stavanger Research center (SSR) has developed a pioneering workflow that provides a calibrated reservoir structure in real-time via integration of surface seismic with ultra-deep azimuthal resistivity inversions, which enables the prediction of reservoir structure up to hundreds of meters ahead of bit, and so increasing the proactivity level of geosteering decisions.

We will be presenting real examples performed while drilling to demonstrate the technological approach. Among them, the case study in the Visund field, located in the Norwegian Continental Shelf where the real-time prediction of structural changes ahead of bit was field tested during the drilling of the horizontal section.

Besides the integrated while drilling approach for the prediction of the reservoir geometry in front of bit, the pioneering technology also refines both the structural and stratigraphic components from borehole to reservoir scale along the horizontal well. Such workflow enables better well placement in complex geological settings and brings geosteering to the next level.