Workflow of Digital Field Mapping and Drone-Aided Survey for the Identification and Characterization of Capable Faults: The Case of a Normal Fault System in the Monte Nerone Area (Northern Apennines, Italy)

Abstract

Field work on the search and characterization of ground effects of a historical earthquake (i.e., the Cagli earthquake in 1781) was carried out using terrestrial and aerial digital tools. The method of capturing, organizing, storing, and elaborating digital data is described herein, proposing a possible workflow starting from pre-field project organization, through reiteration of field and intermediate laboratory work, to final interpretation and synthesis. The case of one of the most important seismic events in the area of the northern Umbria–Marche Apennines provided the opportunity to test the method with both postgraduate students and researchers. The main result of this work was the mapping of a capable normal fault system with a great number of observations, as well as a large amount of data, from difficult outcrop areas. A GIS map and a three-dimensional (3D) model, with the integration of subsurface data (i.e., seismic profiles and recent earthquake distribution information), allowed for a new interpretation of an extensional tectonic regime of this Apennines sector, similar to one of the southernmost areas of central Italy where recent earthquakes occurred on 2016.

Keywords

• GIS
• GPS
• structure-from-motion
• 3D modeling
• historical earthquake
• instrumental seismicity