GITANES: A MATLAB Package for Estimation of Site Spectral Amplification with the Generalized Inversion Technique

The site characterization in terms of the frequency-dependent amplification of the ground motion is one of the main topics in engineering seismology. The generalized inversion technique (GIT) is a well-established approach to evaluate the local amplification from the seismic records acquired during a seismological deployment. However, the implementation of GIT is not straightforward, and its application to different cases could be tricky. We present a MATLAB package, GITANES (GIT ANalysis of Earthquake Spectra), which consists of a user-friendly tool based on GIT for the evaluation of the seismic site amplification from earthquake seismograms recorded by a local network. GITANES also provides the amplitude spectra of the source time function of the recorded seismic events as a by-product of the analysis. The user can execute the workflow interactively from the MATLAB command window or with the aid of the provided graphical user interface (GUI). We demonstrate the GITANES functionality with an application to earthquake recordings acquired within a geophysical survey in the Tagliamento River Valley in northeast Italy.