User Guide Seasonal trends

One key time patterns of anthropogenic activity is to be non uniform in time, as driven by georesource production time patterns. When seasonal patterns for geo-energy production are known, we test in the application how these patterns impact the time series of anthropogenic seismicity. The users choose to test the time pattern a the hourly or daily basis (e.g. mining, injection) or monthly patterns (e.g. reservoir water level, oil and gas production). The service further tests if the time patterns we observed is significant as tested against reshuffled series with the same number of events, in the same range of value (e.g. Lemarchand and Grasso, 2007, Tahir et al. 2012). It allows to accept or to reject the change at a given (e.g. 95%) confidence level. It corresponds to Monte Carlo techniques (e.g. Kelly and Sear, 1984; Lemarchand and Grasso, 2007, Tahir et al. 2012), involving 1000 random sets of key events. This is assessed by random sampling, (including bootstrap procedure), 1000 sets of "synthetic event catalogues". The 1000 sets of synthetic catalogues are then analyzed in the same manner as the real seismicity catalogue to assess the confidence levels for the observed episode distribution.

Allow to capture anthropogenic trends in time series that correspond/fit to geo-resource production type. It allows to extract relationship to production patterns and departure from uniform tectonic seismicity background.