Stress Reorientation and LURR: Implication for Earthquake Prediction using LURR

After reviewing the problems associated with the current implementation of LURR theory, we suggest that taking account of stress field complexity and stress reorientation may resolve these problems. By introducing the concept of Maximum Faulting Orientation (MFO), we propose a new approach for calculating LURR. If the plane on which we choose to define LURR happens to be the MFO, we will obtain an LURR curve with a high peak. Otherwise, if that plane is not the MFO, the LURR anomaly may not appear, even if the plane is the main shock fault plane. Since tectonic stress may change from time to time both regionally and locally, LURR values calculated on a fixed plane will inevitably undulate. Results presented for the cases of California earthquakes provide encouragement for the stress-reorientation explanation and new approach.