Least squares estimation of formation bedding orientation from electromagnetic measurements

One of the challenging aspects in directional electromagnetic measurements is to accurately estimate the formation bedding orientation angle, which is critical to help maintain drilling the wellbore in the sweetest spots of the reservoir. Various existing methods can be both noisy and susceptible to phase wrapping issues. Here we present a new approach for accurately computing the bedding orientation angle, based on least squares technique applied to the acquired voltages. It successfully avoids the phase wrapping issues. Moreover, the angle is computed by minimizing the weighted sum of squared residuals of acquired voltages, which provides more accurate angle estimation owing to a robust mathematic model. This novel approach has been well validated with a large number of cases. The results demonstrate the accuracy and robustness of the method.