Analysis of Aftershock Parameters for the Alaskan Subduction Zone Tectonic Region

On 29 July 2021, a magnitude 8.2 earthquake was felt by over 200 people near Perryville, Alaska. The early aftershock forecasts issued by the USGS use default parameters based on expected productivity within a given tectonic region. These forecasts predicted a slower decrease in aftershock activity than what was observed. Even after the USGS adjusted the aftershock forecast parameters, the forecasts did not improve in the long term. Accurate aftershock predictions are important for maintaining public confidence in disaster alert systems. The question I want to explore is: are the generic parameters used in aftershock forecasting accurately describing the observed aftershock behavior in Alaska? To answer this question, I will use my own R code, USGS aftershock forecasting tools, and linear regression to compare the default parameters with modified ones. This comparison will help determine if this over-prediction is seen in other aftershock sequences.