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<p> </p><p>Satellite Differential Synthetic Aperture Radar Interferometry (DInSAR) is a well-known technique that allows investigation surface displacements affecting large areas (km-scale) on the Earth, in both natural and anthropogenic hazard scenarios, with rather limited costs and a centimeter accuracy. In particular, in the last two decades, the effectiveness of the satellite DInSAR technology for ground deformation analysis induced by seismic events, and its crucial role in the emergency, have been largely demonstrated. In this context, we present a complete open-source tool of DInSAR technique, starting from the dataset download up to the data processing and interpretation of the deformation field. SAR imageries from Sentinel-1 satellite of the Copernicus are collected. Data processing is executed thanks to SNAP software from ESA (https://earth.esa.int/eogateway/tools/snap), and using snappy module in Python that allows interacting with the Java API of SNAP to avoid eventual bugs and to automatize the process. The workflow will include not only the work chain to obtain the displacement map along the satellite Line of Sight (LOS), but also several modules that the operator can exploit to retrieve the vertical and horizontal (east-west) displacement field when, obviously, on the same seismic event, at least two independent acquisitions geometries (at least one ascending and one descending orbit), are available. The workflow is applied to three case studies characterized by compressional and strike-slip tectonics: Bandar-Abbas seismic sequence, Iran (November 2021); Petrinya earthquake, Croatia (December 2020) and Menuyan earthquake, China (January 2022). The final scope of this research is to provide a single, automatic and repeatable product to create a two-dimensional deformation map with only open-source tools. This method is helpful not only for its simplicity as it can be adopted also by beginning users in the very first stage of approaching DInSAR technique, but also for the extension of studies related to seismic areas as a combination with the on-field observation in order to mitigate their seismic risk.</p>

<p>In the last three decades, remote sensing techniques, such as Differential Synthetic Aperture Radar Interferometry (DInSAR), have been exploited for investigating, with high accuracy, ground displacement phenomena. Large seismic events can trigger deformations at the surface, which are controlled by the active faults and the intercepted lithologies.<br />In 2016-2017, a long earthquake sequence struck the Apennines in central Italy, producing impressive surface ruptures attributed to the 24 August Mw 6.0 and 30 October Mw 6.5 mainshocks. These ruptures were investigated and mapped by field geologists soon after the earthquakes, and during the following years also by remote sensing data.</p> <p>We present detailed maps of the surface deformation pattern produced by the M. Vettore Fault System (VFS) during the October 2016 earthquakes. The DInSAR analysis has been retrieved from ALOS-2 SAR data, via the Parallel Small BAseline Subsets (P-SBAS) algorithm. At the local scale, we identify a large number of surface ruptures, most of which already observed in the field. At the large scale, we trace a set of five geological cross-sections to inspect a possible link between the coseismic vertical displacement, the lithology distribution and the tectonic structures of the area (i.e., thrusts, normal faults). On these sections, we also project the seismicity distribution recorded during October 2016.</p> <p>The integration of such datasets allows the recognition of an important geological control in the overall distribution of the deformation, which shows maximum values in correspondence of the carbonatic multilayer and minimum values within the clastic succession. The distribution of seismicity allows also us to distinguish seismogenic by aseismic slip associated with fault ruptures.</p> <p>Along the sections, we observe a typical long-wavelength convex curvature of the subsiding block, not directly recognizable in the field.  In the area of maximum subsidence, this curvature is interrupted by an anthitetic fault at which is not associated with any seismicity. In addition, we observe that further deformation is localized at the footwall of the VFS, corresponding to the hangingwall block of an important thrust fault, where shallow seismicity was also recorded. Here, we observe that the coseismic deformation tends to decrease toward the outcropping thrust. In the south sector, instead, we do not observe a control of regional thrusts acting as a barrier to the deformation.</p> <p>The results of this work demonstrate that the integration of surface geology, remote sensing data and seismicity, can lead to a better understanding of the influence of geological structures on the distribution of the surface deformation associated with earthquakes.</p>