Photographic collection of the coseismic geological effects originated by the 24th August 2016, Amatrice (Central Italy) seismic sequence

Abstract

We present a collection of pictures showing the geological effects produced in the natural or in the built environment by the 2016 Amatrice earthquake sequence in Central Italy. The sequence hit a relatively wide area straddling the conterminous regions of Lazio, Abruzzo, Umbria and Marche, causing almost 300 deaths, thousands of injured and more than 3000 displaced people, severe damage (up to X MCS intensity) of a number of historical centres, and an estimated economic toll of more than 4 billion Euros. The August 24th MW 6.0 mainshock occurred ~1 km west of Accumoli on a ~NW-striking, SW-dipping normal fault; it was followed one hour later by a strong aftershock (MW 5.4) located 4 km east of Norcia. The Emergeo Working Group surveyed a ~750 km2 large area, recording more than 3200 observations of several types of coseismic effects: fractures (i.e. small surface open cracks with ≤1 cm displacement), ruptures (i.e. surface cracks with both vertical and horizontal displacements >1cm), landslides and remobilized deep-seated gravitational slope deformations, and other effects related to shaking (e.g. clast extrusions, soil remobilization, etc.). Most of the coseismic geological effects were collected through field survey; aerial platforms such as helikite and unmanned aerial vehicles (UAVs), along with a helicopter flight, allowed us to achieve additional documentation of the most prominent coseismic surface ruptures. The photographic dataset consists of 100 pictures of coseismic geological effects observed over an area extending ~45 km and ~10-15 km in the NW-SE and in the NE-SW directions, respectively. The pictures – shot between August 24 and October 7 - are grouped into five main geographical areas of occurrence (Castelluccio Plain-Alta Valnerina; Monte Vettore; Monte Vettoretto-Forca di Presta; Valle del Tronto; Monti della Laga) and presented by locality of observation; each photo reports a series of information such as type of effect, site of observation, and geographical coordinates (decimal degrees). Figure 1 shows a map of the pictures sites along with the location of the two main shocks of the sequence; solid rectangles show the location of the five areas of geographical distribution of the photos. The complete description of the coseismic geological effects induced by the Amatrice sequence, their relation with the aftershock area along with the description of the technologies used for data sourcing and processing are shown in Emergeo Working...