Fast 2D Inversion for Enhanced Real-Time Reservoir Mapping While Drilling

The new reservoir mapping-while-drilling technology provides enough data so that a real-time reservoir map can be created through inversion for a layered medium. These reservoir maps are used to optimize well placement and to improve reservoir understanding. Complex reservoirs can be imaged, but the assumption of a layered medium loses its validity when the reservoir cannot be approximated using 1D model locally, i.e., when the reservoir structure varies on the scale of the tool spacing. To improve reservoir mapping performance in such scenarios, an unbiased approximate 2D inversion is introduced that minimizes the error to the layer medium approximation of the reservoir. It is suited for any mildly 2D scenario in which the reservoir does not change abruptly. The method is validated on synthetic and field datasets.