This is part of the regular Seismcity Seminar Series

Talk 1: Abdelhak Talbi - Analysis of Earthquake Interevent Time Distribution

A simple mixed model is presented and fitted to earthquake interevent time distribution. The model uses power law and Weibull distributions at short and long interevent time ranges respectively. The implementation and limitations of the former proposed model are discussed with some applications in the study of earthquake clustering and seismicity forecast.

Talk 2: Paul A. Rydelek - Tidal analysis of data from pressure sensors located at the Sagami trough, central Japan

At the sea-bottom of the Sagami trough subduction zone, south of the metropolitan area, central Japan, both temperature and pressure are continuously monitored with on-line tsunami sensors. These sensors are capable of measuring the changes in the corresponding thickness of the sea water layer to an accuracy of order mm, which suggests that the semidiurnal and diurnal oceanic tides are recorded with high resolution. We determined the amplitudes and phases of the major components of the periodic oceanic tides from a least squares analysis of a 1.5-year record of pressure data that partly included a temperature dependence. These results were then compared against those predicted from an oceanic model based on TOPEX/Poseidon data. Whereas we find good overall agreement between the observations and predictions, we also find some systematic differences. On average, the amplitudes of the tides in the oceanic model are found to mainly exceed the observed tides by several percent. Phase differences between observations and predictions are very small in the semidiurnal band but show departures in the diurnal band where observations lead predictions. Uncertainties in the oceanic models and unmodeled temperature effects may be able to explain these differences.