← Back to Sessions

Time Series Analysis From a High-Definition Italian Catalog: Seismicity Rates and Gutenberg-Richter b-Value Evaluation

Description: 

The high-resolution earthquake catalog related to the seismic activity of the Alto Tiberina fault system (Northern Apennine, Central Italy), constructed from the seismic network of the Alto Tiberina Near Fault Observatory (TABOO), was analysed by statistical methods from a seismological perspective.

To bring new information on the study of earthquakes preparatory phases and to identify possible tectonic stress indicators, we focused on the reliable time series computation of the seismicity rates and of the Gutenberg-Richter b-value.

In this work, the time series were evaluated starting from the generation of the stochastic declustered catalog obtained using the 2D ETAS Model.

The capability of the algorithm based on the ETAS model to recognize and distinguish the triggered seismicity from the background allowed evaluating the daily seismicity rates and b-value variations for both the spontaneous and triggered earthquakes.

Moreover, to overcome the problems due to building b-value time series for a non-uniform temporal distribution of seismicity, we considered the weighted likelihood approach for a more robust b-value estimation and we implemented the weighted likelihood algorithm using weights obtained by 2D ETAS declustering, in order to evaluate changes in b-values both for background and triggered seismicity.

The obtained time series, in particular the b-value time series, are different from the ones obtained using the classical rolling window approach for the b-value computation, indicating that some of the b-value fluctuations are related to the natural statistical variability of the parameter.

Session: New Methods and Models for More Informative Earthquake Forecasting [Poster]

Type: Poster

Date: 4/19/2023

Presentation Time: 08:00 AM (local time)

Presenting Author: Giuseppe Falcone

Student Presenter: No

Invited Presentation: 

Authors