Elias Rafn Heimisson , Jean-Philippe Avouac 

Oscillatory stresses are ubiquitous on earth and other solid-surface bodies. Tides and seasonal signals perpetually stress faults in the crust. Relating seismicity to these stresses offers fundamental insight into earthquake triggering. We present a simple model that describes seismicity rate due to perpetual oscillatory stresses. The model applies to large amplitude, non-harmonic, and quasi-periodic stressing. However, it is not valid for periods larger than the characteristic time $t_a$. We show that seismicity rate from short-period stressing scales with the stress amplitude, but for long-periods with the stressing rate. Further, that background seismicity rate $r$ is equal to the average seismicity rate during short-period stressing. We suggest $A\sigma_0$ may be underestimated if stresses are approximated by a single harmonic function. We revisit Manga et al. (2019), which analyzed the tidal triggering of Marsquakes, and provide a re-scaling of their seismicity rate response that offers a self-consistent comparison of different hydraulic conditions.