This research focuses on the performance of GNSS receiver carrier phase tracking loops for earthquake monitoring systems. An earthquake was simulated using a hardware simulator; position, velocity and acceleration displacements were obtained to recreate the dynamics of the 2011 Tohoku earthquake, Japan. Using a software defined receiver, various tracking bandwidths and integration times were tested. Using the phase lock indicator and carrier-to-noise ratio as metrics, an adaptive carrier tracking loop was successfully designed and tested to maximize performance for this application. Four different simulations were done to assess the performance of the adaptive carrier tracking loop. Two simulations with carrier-to-noise ratios greater and less than 35 dB-Hz were done using the original dynamics of the 2011 Tohoku earthquake. The other two simulations tested were the dynamics of the same earthquake scaled by a factor of 10, with carrier-to-noise ratios greater and less than 35 dB-Hz.