# Surface ruptures following the 30 October 2016 Mw 6.5 Norcia earthquake, central Italy

R. Civico, S. Pucci, F. Villani, L. Pizzimenti, P. de Martini, R. Nappi,

Matthieu Ferry, Frédérique Leclerc, A. Delorme

► To cite this version:

R. Civico, S. Pucci, F. Villani, L. Pizzimenti, P. de Martini, et al. Surface ruptures following the 30 October 2016 Mw 6.5 Norcia earthquake, central Italy. Journal of Maps, 2018, 14 (2), pp.151 - 160. 10.1080/17445647.2018.1441756. hal-01738142

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# Surface ruptures following the 30 October 2016 M<sub>w</sub> 6.5 Norcia earthquake, central Italy

R. Civico, S. Pucci, F. Villani, L. Pizzimenti, P. M. De Martini, R. Nappi & the Open EMERGEO Working Group

To cite this article: R. Civico, S. Pucci, F. Villani, L. Pizzimenti, P. M. De Martini, R. Nappi & the Open EMERGEO Working Group (2018) Surface ruptures following the 30 October 2016 M<sub>w</sub> 6.5 Norcia earthquake, central Italy, Journal of Maps, 14:2, 151-160, DOI: 10.1080/17445647.2018.1441756

To link to this article: https://doi.org/10.1080/17445647.2018.1441756

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# Surface ruptures following the 30 October 2016 M<sub>w</sub> 6.5 Norcia earthquake, central Italy

R. Civico ID, S. Pucci ID, F. Villani ID, L. Pizzimenti ID, P. M. De Martini ID, R. Nappi ID and the Open EMERGEO Working Group*

Istituto Nazionale di Geofisica e Vulcanologia, Italy

## ABSTRACT

We present a 1:25,000 scale map of the coseismic surface ruptures following the 30 October 2016 M<sub>w</sub> 6.5 Norcia normal-faulting earthquake, central Italy. Detailed rupture mapping is based on almost 11,000 oblique photographs taken from helicopter flights, that has been verified and integrated with field data (>7000 measurements). Thanks to the common efforts of the Open EMERGEO Working Group (130 people, 25 research institutions and universities from Europe), we were able to document a complex surface faulting pattern with a dominant strike of N135°-160° (SW-dipping) and a subordinate strike of N320°-345° (NE-dipping) along about 28 km of the active Mt. Vettore-Mt. Bove fault system. Geometric and kinematic characteristics of the rupture were observed and recorded along closely spaced, parallel or subparallel, overlapping or step-like synthetic and antithetic fault splays of the activated fault systems, comprising a total surface rupture length of approximately 46 km when all ruptures were considered.

## ARTICLE HISTORY

Received 10 July 2017
Revised 27 December 2017
Accepted 9 February 2018

## KEYWORDS

Surface faulting; coseismic ruptures; normal faulting; geological prompt surveys; 2016–2017 seismic sequence; central Italy

## 1. Introduction

Initiating in August 2016, a series of moderate to large earthquakes struck the central Apennines producing severe damage in several small towns including Amatrice, Norcia and Visso (Figure 1). The earthquakes resulted in almost 300 casualties and left more than 20,000 homeless. These events came seven years after the 6 April 2009 M<sub>w</sub> 6.1 L’Aquila earthquake (Herrmann, Malagnini, & Munafò, 2011). The seismic sequence (Chiaraluce et al., 2017 and references therein; Figure 1) started with an M<sub>w</sub> 6.0 mainshock (24 August), which was followed by an M<sub>w</sub> 5.9 mainshock on 26 October located 25 km to the northwest

to culminate on 30 October 2016, in the largest shock of the sequence, an M<sub>w</sub> 6.5 near the town of Norcia. Other events occurred in the southern sector of the sequence on 18 January 2017, with a maximum M<sub>w</sub> of 5.5 (Figure 1).

The 30 October 2016 (06:40 UTC) M<sub>w</sub> 6.5 Norcia mainshock was the strongest Italian seismic event since the 1980 M<sub>s</sub> 6.9 Irpinia earthquake (Bernard & Zollo, 1989; Westaway & Jackson, 1987). The Norcia mainshock occurred less than 5 km NE of the village of Norcia (Figure 1) as a result of upper crustal normal faulting on a nearly 30-km-long, NW-SE oriented and SW dipping fault system known as Mt. Vettore-Mt. Bove (VBFS). The aftershocks of the 2016–2017 central

**CONTACT** R. Civico

<figure><img src="image_15.png" /></figure>

riccardo.civico@ingv.it

<footnote>*Open EMERGEO Working Group: F. Agosta<sup>6</sup>, G. Alessio<sup>1</sup>, L. Alfonsi<sup>1</sup>, M. Amanti<sup>2</sup>, S. Amoroso<sup>1</sup>, D. Aringoli<sup>5</sup>, E. Auciello<sup>9</sup>, R. Azzaro<sup>1</sup>, S. Baize<sup>19</sup>, S. Bello<sup>9</sup>, L. Benedetti<sup>20</sup>, A. Bertagnini<sup>1</sup>, G. Binda<sup>3</sup>, M. Bisson<sup>1</sup>, A. M. Blumetti<sup>2</sup>, L. Bonadeo<sup>3</sup>, P. Boncio<sup>9</sup>, P. Bornemann<sup>25</sup>, S. Branca<sup>1</sup>, T. Braun<sup>1</sup>, F. Brozzetti<sup>9</sup>, C.A. Brunori<sup>1</sup>, P. Burrato<sup>1</sup>, M. Caciagli<sup>1</sup>, C. Campobasso<sup>2</sup>, M. Carafa<sup>1</sup>, F. R. Cinti<sup>1</sup>, D. Cirillo<sup>9</sup>, V. Comerci<sup>2</sup>, L. Cucci<sup>1</sup>, R. De Ritis<sup>1</sup>, G. Deiana<sup>5</sup>, P. Del Carlo<sup>1</sup>, L. Del Rio<sup>11</sup>, A. Delorme<sup>21</sup>, P. Di Manna<sup>2</sup>, D. Di Naccio<sup>1</sup>, L. Falconi<sup>7</sup>, E. Falcucci<sup>1</sup>, P. Farabollini<sup>5</sup>, J.P. Faure Walker<sup>16</sup>, F. Ferrarini<sup>9</sup>, M.F. Ferrario<sup>3</sup>, M. Ferry<sup>22</sup>, N. Feuillet<sup>21</sup>, J. Fleury<sup>20</sup>, U. Fracassi<sup>1</sup>, C. Frigerio<sup>3</sup>, F. Galluzzo<sup>2</sup>, R. Gambillara<sup>3</sup>, G. Gaudiosi<sup>1</sup>, H. Goodall<sup>15</sup>, S. Gori<sup>1</sup>, L. C. Gregory<sup>15</sup>, L. Guerrieri<sup>2</sup>, S. Hailemikael<sup>7</sup>, F. Iezzi<sup>14</sup>, C. Invernizzi<sup>5</sup>, D. Jablonska<sup>5</sup>, E. Jacques<sup>21</sup>, H. Jomard<sup>19</sup>, V. Kastelic<sup>1</sup>, Y. Klinger<sup>21</sup>, G. Lavecchia<sup>9</sup>, F. Leclerc<sup>23</sup>, F. Liberi<sup>9</sup>, A. Lisi<sup>1</sup>, F. Livio<sup>3</sup>, L. Lo Sardo<sup>8</sup>, J. P. Malet<sup>24</sup>, M. T. Mariucci<sup>1</sup>, M. Materazzi<sup>5</sup>, F. Mazzarini<sup>1</sup>, K. J. W. McCaffrey<sup>17</sup>, A. M. Michetti<sup>3</sup>, Z. K. Mildon<sup>16</sup>, P. Montone<sup>1</sup>, M. Moro<sup>1</sup>, R. Nave<sup>1</sup>, M. Odin<sup>24</sup>, B. Pace<sup>10</sup>, S. Paggi<sup>5</sup>, N. Pagliuca<sup>1</sup>, G. Pambianchi<sup>5</sup>, D. Pantosti<sup>1</sup>, A. Patera<sup>1</sup>, E. Pérouse<sup>20</sup>, G. Pezzo<sup>1</sup>, L. Piccardi<sup>4</sup>, P. P. Pierantoni<sup>5</sup>, M. Pignone<sup>1</sup>, S. Pinzi<sup>1</sup>, E. Pistolesi<sup>5</sup>, J. Point<sup>24</sup>, A. Pozzi<sup>3</sup>, M. Proposito<sup>7</sup>, C. Puglisi<sup>7</sup>, I. Puliti<sup>12</sup>, T. Ricci<sup>1</sup>, L. Ripamonti<sup>13</sup>, M. Rizza<sup>20</sup>, G. P. Roberts<sup>14</sup>, M. Roncoroni<sup>13</sup>, V. Sapia<sup>1</sup>, M. Saroli<sup>8,1</sup>, A. Sciarra<sup>1</sup>, O. Scotti<sup>19</sup>, G. Skupinski<sup>25</sup>, A. Smedile<sup>1</sup>, G. Tarabusi<sup>1</sup>, S. Tarquini<sup>1</sup>, S. Terrana<sup>3</sup>, J. Tesson<sup>20</sup>, E. Tondi<sup>5</sup>, A. Valentini<sup>10</sup>, R. Vallone<sup>1</sup>, J. Van der Woerd<sup>24</sup>, P. Vannoli<sup>1</sup>, A. Venuti<sup>1</sup>, E. Vittori<sup>2</sup>, T. Volatili<sup>5</sup>, L. N. J. Wedmore<sup>15,16</sup>, M. Wilkinson<sup>18</sup>, M. Zambrano<sup>5</sup></footnote>
<figure><img src="image_16.png" /></figure>

<figure><img src="image_17.png" /><figcaption>**Figure 1.** The 2016–2017 central Italy seismic sequence as recorded by the INGV Italian National Seismic Network (data from ISIDe – Italian Seismological Instrumental and Parametric Data-Base – http://iside.rm.ingv.it) for the time period 24 August 2016 through 23 January 2017. Stars indicate the mainshocks of the sequence. Time Domain Moment Tensor focal mechanisms of the three main earthquakes of the sequence are from the INGV web page (http://cnt.rm.ingv.it). Historical seismicity form CPTI15 (Rovida et al., 2016). Faults are compiled from Centamore et al. (1992), Pierantoni et al. (2013) and Galli et al. (2008). The white-dashed box encloses the area of the Main Map.</figcaption></figure>

Italy seismic sequence are confined to the upper crust (10–12 km maximum depth) and follow a roughly NW-SE trend for ca. 80 km between the towns of Camerino to the north and Pizzoli to the south (Chiaraluce et al., 2017).

This area of the central Apennines chain is characterized by a Quaternary NE-SW oriented extensional regime overprinting NE-verging thrust sheets

(Lavecchia, Brozzetti, Barchi, Menichetti, & Keller, 1994; Vai & Martini, 2001), which mostly comprise Meso-Cenozoic carbonate rocks and Miocene flysch deposits. In the past 30 years, several attempts have been made to explain the space–time migration of the coupled extension–compression system affecting the Apennines. The most accepted idea is that backarc extension related to the subduction roll-back
<figure><img src="image_18.png" /></figure>

(Carminati & Doglioni, 2012 and references therein) may be a reliable large-scale underlying mechanism. Mantle uplift sustaining long-wavelength topography is invoked by D'Agostino, Jackson, Dramis, and Funi-ciello (2001) and by Chiarabba and Chiodini (2013). Extension is accommodated by a complex array of NW-SE and NNW-SSE striking, mainly SW dipping, up to 30-km-long, active normal fault systems. The cumulative rate of extension across the region is ~1-3 mm/year based on the modeling of geodetic obser-vations (Carafa & Bird, 2016; D'Agostino, 2014). The main active tectonic structures in the area affected by the 2016-2017 seismic sequence are the Mt. Vettore-Mt. Bove (Calamita, Pizzi, & Roscioni, 1992; Calamita & Pizzi, 1992, 1994; Cello, Mazzoli, Tondi, & Turco, 1997; Pizzi, Calamita, Coltorti, & Pieruccini, 2002), the Laga Mountains (Boncio, Lavecchia, Milana, & Rozzi, 2004; Galadini and Galli, 2000, 2003; Galli, Galadini, & Pantosti, 2008, also known as Mt. Gorzano fault), the Norcia (Galli, Galadini, & Calzoni, 2005) and the Montereale (Lavecchia et al., 2012; Civico et al., 2016) fault systems (Figure 1), which show Qua-ternary geologic slip rates ranging between 0.5 and 1.3 mm/year (Barchi et al., 2000; Boncio et al., 2004; Pizzi et al., 2002). Geological and paleoseismological studies conducted by Galadini and Galli (2003) along the VBFS anticipated that this active tectonic structure was one of the main seismic gaps of the central Apennines, potentially responsible for up to M 6.5 seismic event.

The area hit by the 2016–2017 seismic sequence has been repeatedly struck by $5.2 < M_w < 6.2$ earthquakes in the last 400 years, with the largest local earthquake occurring in 1639 (Io 9–10 MCS, $M_w$ 6.2 – Rovida, Locati, Camassi, Lolli, & Gasperini, 2016). Apart from the 1703 earthquake sequence (with $M_w$ up to 6.9), the broader region was the locus of other damaging moderate-sized earthquakes that struck central Italy in recent times: the $M_w$ 5.8 1979 Norcia to the west (Brozzetti & Lavecchia, 1994; Deschamps, Iannaccone, & Scarpa, 1984), the $M_w$ 6.0 1997 Umbria-Marche (Colfiorito) earthquake sequence to the northwest (Amato et al., 1998; Boncio & Lavecchia, 2000; Ferrarini, Lavecchia, de Nardis, & Brozzetti, 2014) and the $M_w$ 6.1 2009 L’Aquila sequence to the southeast Chiaraluce et al., 2011; Lavecchia et al., 2012; Valoroso et al., 2013).

Within the Apennine chain, evidence of surface faulting was documented after the catastrophic $M_s$ 6.9–7.0, 1915 Avezzano earthquake (Galadini & Galli, 1999; Michetti, Brunamonte, Serva, & Vittori, 1996; Oddone, 1915; Serva, Blumetti, & Michetti, 1988) as well as after the $M_s$ 6.9, 1980 Irpinia earthquake (Pantosti & Valensise, 1990; Westaway & Jackson, 1984). More recently, for the $M_w$ 6.1, 2009 L’Aquila earthquake, geologic data (Boncio et al., 2010; EMERGEO Working Group, 2010; Vittori et al., 2011) documented the occurrence of surface faulting. Conversely, the

occurrence of primary seismogenic surface rupture remains controversial for the $M_w$ 6.0 1997 Colfiorito earthquake (e.g. Basili et al., 1998; Cello et al., 2000; Cinti, Cucci, Marra, & Montone, 1999; Mildon, Roberts, Faure Walker, Wedmore, & McCaffrey, 2016).

Coseismic surface ruptures were observed following the $M_w$ 6.0 24 August 2016 normal-faulting Amatrice earthquake (Figure 1). Ruptures trending ~N155° with prevalent dip-slip kinematics, SW side down (average displacement of ~0.13 m) were mapped for ~5.2 km along the southern portion of the VBFS (EMERGEO Working Group, 2016; Lavecchia et al., 2016; Pucci et al., 2017). These coseismic features were interpreted as the result of primary surface fault-ing by Livio et al. (2016), Aringoli et al. (2016) and Pucci et al. (2017), while much less clear (1–2 cm of surface displacement) and discontinuous coseismic features were recorded along the Laga Mts. fault system by most of the research groups working in the area. Following the 26 October 2016, $M_w$ 5.9 Visso earthquake (Figure 1), only sparse and discontinuous (each up to few hundred of meters long) ground rup-tures were observed for a minimal length of about 7–10 km (Bendia et al., 2017) along the northern portion of the VBFS (approximately between the villages of Cupi and Casali, Figure 1), with an average vertical dis-placement of ~0.15 m. Similar to the preceding event, the Visso earthquake surface ruptures show an average N145° strike and prevalent dip-slip kinematics, with the SW side down. Noteworthy, the field survey of the coseismic effects of the Visso event was not fully achieved having been overprinted by the occurrence of the 30 October $M_w$ 6.5 mainshock.

The 30 October mainshock occurred with an epi-center close to the town of Norcia (Figure 1), and pro-duced surface coseismic effects on the natural environment over a >400 km² wide area. The coseismic effects mainly consist of primary surface ruptures (those directly related to the earthquake fault; Figures 2 and 3), together with other coseismic effects related to ground shaking and permanent deformation (e.g. landslides, hydrological variations and liquefaction). An almost continuous NW-SE pattern of primary sur-face ruptures was observed for an overall extent of about 28 km along the VBFS, clearly overprinting and magnifying all the 24 August and, partially, the 26 October 2016 ground breaks. Surface rupture dis-placement exhibits predominantly normal dip-slip kin-ematics, with an average coseismic throw of ~0.3 m. However, more than 2 km of almost continuous rup-ture in the southernmost portion of the activated fault system displayed >1 m average throw, and excep-tionally high local peak throws up to ~2.4–2.6 m were observed along the so-called Cordone del Vettore. In general, the ruptures are organized in a systematic pat-tern of dominantly synthetic (N135°-160° striking, SW-dipping) and subordinately antithetic (N320°-
<figure><img src="image_19.png" /></figure>

<figure><img src="image_20.png" /></figure>

**Figure 2.** Examples of coseismic ruptures along the Mt. Vettore–Mt. Bove fault system as seen from helicopter surveys. White arrows mark the trace of the surface ruptures. (a) View of the continuous and stepping splay of the coseismic ruptures along the western Mt. Vettoretto flank (42.8083 N, 13.2630 E); (b) antithetic coseismic rupture in the middle sector of the VBFS (42.8489 N, 13.2213 E); (c) set of parallel coseismic ruptures along the western Mt. Vettore flank (42.8261 N, 13.2454 E); (d) Cordone del Vettore ruptured splay (42.8165 N, 13.2554 E); (e) coseismic ruptures along the Piano Grande di Castelluccio fault splay (42.8194 N, 13.2230 E) and (f) antithetic coseismic free-face following a cumulative fault scarp in both bedrock and alluvium (42.8531 N, 13.2119 E).
<figure><img src="image_21.png" /></figure>

<figure><img src="image_22.png" /></figure>

**Figure 3.** Examples of coseismic ruptures along the Mt. Vettore–Mt. Bove fault system as seen in the field. (a) Bedrock fault plane with freshly exposed free-face at Mt. Redentore (42.8189 N, 13.2522 E); note that the upper part of the free-face was exposed during the 24 August earthquake (10–20 cm); (b) right-stepping ruptures affecting colluvium, white arrows mark the trace of the ruptures in the distance (42.8488 N, 13.2213 E); (c) close view of decimetric throw affecting soil (42.8820 N, 13.2267 E); (d) metre-scale coseismic scarp cutting a small gully (42.9139 N, 13.1917 E); (e) frozen coseismic rupture (42.8751 N, 13.2290 E); (f) coseismic exhumation of buried bedrock fault plane covered by thin soil (42.8138 N, 13.2460 E).

345° striking, NE-dipping) strands. Notably, the alignment of ground ruptures typically follows the trace of mapped faults (Pierantoni, Deiana, & Galdenzi, 2013

and references therein), although in some cases, the coseismic ruptures occurred along fault splays that were not previously recognized. Subordinate and very
<figure><img src="image_23.png" /></figure>

discontinuous ruptures affected the SW edge of the Piano Grande basin and the Norcia town area.

Detailing all coseismic surface effects is crucial to identify and define primary surface faulting and its structural arrangement. This contributes to image the shallow-crust brittle deformation complexities and may provide useful information for describing the seismic source. Moreover, understanding the relations between the seismic source at depth and its evidence at the surface creates the basis for using the active faults at the surface to image which are the faults that can rupture next. Furthermore, this work provides new data on surface faulting in extensional domains, both on the earthquake causative fault splays and on other fault segments where deformation is distributed, implementing the community-sourced, worldwide and unified database of surface ruptures associated with earthquakes (SURface Rupture Earthquake (SURE) database, International Union for Quaternary Research (INQUA) project 2016–2019 – http://www. earthquakegeology.com/index.php?page=projects&s=4). The final goals of this database are: (1) to generate a standardized method for describing surface ruptures and (2) to improve Probabilistic Fault Displacement Hazard Analysis (PFDHA) models through the assimilation of surface ruptures data from different earthquakes. Our data may also contribute updating the empirical relationships used to estimate the hazard related to surface faulting and to define the approximate magnitude of paleo-earthquakes (Stirling, Goded, Berryman, & Litchfield, 2013; Wesnousky, 2008).

The widespread occurrence of the ruptures, the large extent of the affected area, the amount of displacement and the complexity of the rupture geometry required a huge effort to document the impact that an $M_w$ 6.5 seismic event had on the territory. Rapid and spatially dense collection of accurate surface rupture data after earthquakes can support emergency response, help coordinate scientific response and constrain coseismic slip that may be erased by degradation of fault scarps or by road/infrastructure repair, as well as overprinted by postseismic slip.

This paper represents a first synthesis of the common efforts of several European teams of earth scientists (Open EMERGEO Working Group – 130 people from 25 different research institutions and universities coordinated by the Istituto Nazionale di Geofisica e Vulcanologia – INGV). This is the first time that such a broad coordination of geoscientists was successful in studying together the geological coseismic effects following a large European earthquake. The response of the Open EMERGEO Working Group was focused on the detailed recognition and mapping from aerial and field surveys of: (1) the total extent of coseismic surface ruptures following the 30 October earthquake, (2) their geometric and kinematic characteristics and (3) the coseismic displacement distribution along the

activated fault system. The full dataset supporting points 2 and 3 is presented in Villani et al., 2018.

In this study, we present a detailed and comprehensive report (Main Map) of the post-30 October 2016 $M_w$ 6.5 earthquake surface ruptures along the VBFS and adjacent fault systems (e.g. Norcia Fault System). Mapping was carried out using both field observations and aerial surveys. It should be noted that due to the complex behavior of this seismic sequence with multiple mainshocks occurring close in time, our mapping includes surface deformation related to all of the mainshocks that occurred in the area (namely: the 24 August, 26 October and 30 October 2016 events).

## 2. Methods

Rapid and spatially dense collection of accurate surface rupture data after earthquakes can support emergency response, help coordinate scientific response and constrain coseismic slip that may be erased by degradation of fault scarps or by road/infrastructure repair, as well as overprinted by postseismic slip. Therefore, the Open EMERGEO Working Group began surveying the coseismic geological effects at the surface within hours of the 30 October 2016 mainshock. One of the main challenges for mapping the post-30 October coseismic surface rupture was to identify and locate the primary rupture path through a complex network of faults (Calamita et al., 1992; Pierantoni et al., 2013; Pizzi et al., 2002) within a wide and rugged terrain region (>400 km²) with elevations up to ~2400 m. By the end of 31 October, a first picture of the surface rupture extent and of its general pattern was established by means of a helicopter flight, which formed the basis for planning the subsequent field and aerial surveys. Priorities were set to rapidly examine and document features that: (a) were likely to be quickly degraded by possible snowfall/rain and (b) posed a potential risk to people (e.g. coseismic ruptures in close proximity or intersecting roads/infrastructures, or incipient landsliding along steep slopes).

Comprehensive mapping of the extent and the geometric characteristics of the surface ruptures was facilitated by oblique photographs (more than 11,000 digital images, see Figure 2) taken with six helicopter flights, for a total of 12 h flight. This was particularly useful in scarcely accessible or dangerous areas. Oblique photographs were taken with two handheld cameras equipped with almost the same 24-megapixel APS-C CMOS sensor (Sony ILCE-5100 and Nikon D5300) and capable of a maximum resolution of 6000 × 4000 pixels. Photographs were acquired as raw image files with shutter speeds (a.k.a exposure times) between 1/320 and 1/2000 to avoid motion blur and using focal lengths variable from 24 to 75 mm (35 mm equivalent focal length). Each photo was then associated to its own geographical coordinates (latitude, longitude and
<figure><img src="image_24.png" /></figure>

altitude) using track files recorded with an external
GPS receiver.

The coseismic ruptures detected from aerial surveys
were traced on screen at up to 1:500 scale with the help
of satellite and aerial imagery from Bing Maps Aerial
and World Imagery web services. In addition, 0.5 m
resolution Pleiades satellite images were provided by
European Space Agency (ESA – CEOS_seismic pilot
program) and *Centre National des Etudes Spatiales*
(CNES) from France following the 24 August and the
30 October shocks. All the data were subsequently
checked and integrated with field measurements, also
taken in forested areas where remote surveys resulted
less effective. Field measurements were greatly aided
by the use of mobile devices equipped with a specific
software employing GPS, compass and orientation sen-
sors (Rocklogger© mobile app, www.rockgecko.com),
which allowed for quick and accurate structural data
collection and real-time sharing (see details of the
method in EMERGEO Working Group, 2012). The
huge amount of structural data collected was stored,
managed and shared through a georeferenced database.
The field measurements database (>7000 observation
points) of the coseismic geological effects at the surface
following the 30 October 2016 M<sub>w</sub> 6.5 event is available
in Villani et al., 2018. This database is presented in a
specifically designed spreadsheet containing the full
dataset of the geometric and kinematic characteristics
of the ruptures.

Rupture traces are included in the Main Map as a
line coverage. Rupture traces with measured or
observed vertical offset are plotted with a red continu-
ous line with tick marks on the downthrown side, while
a blue continuous line has been used to show a rupture
trace without measured or observed vertical offset. The
traces of the recognized landslide head scarps are also
reported (green lines). Rupture and landslide head
scarps traces are drawn over a topographic base map
built as a multilayer of: (a) hillshaded relief from the
TINITALY (Triangular Irregular Network of Italy)
10-m-resolution digital elevation model (Tarquini
et al., 2007), (b) World Imagery web service and (c)
contour lines (20-m interval) and toponyms from vec-
torial topographic maps at 1:10,000 scale (C.T.R. from
Regione Umbria and Regione Marche). The Main Map
is reduced at 1:25,000 scale, as this is the best compro-
mise between the paper size, the extent of the study
area and the desired map detail.

**3. Conclusions**

Following the 30 October 2016 M<sub>w</sub> 6.5 Norcia earth-
quake, a complex surface faulting pattern was observed
and recorded along the causative VBFS and the nearby
fault systems (e.g. Norcia Fault System). Thanks to the
common efforts of the Open EMERGEO Working
Group (130 people from 25 different research

institutions and universities from Europe), we were
able to record in high resolution the total extent of
the coseismic surface ruptures and their geometric
and kinematic characteristics. Noteworthy, the mapped
ruptures also include all those that occurred after the
24 August M<sub>w</sub> 6.0 event and partially those related to
the 26 October M<sub>w</sub> 5.9 shock.

Remote sensing surveys verified and integrated with
field data showed an almost continuous alignment of
ground ruptures for an overall NW-SE extent of
about 28 km along the VBFS. Field observations after
the 30 October 2016 earthquake reveal that the surface
rupture pattern of this earthquake, involving closely
spaced, parallel or subparallel, overlapping or step-
like synthetic and antithetic fault splays pertaining to
the VBFS, can be considered to be one of the most
complex recorded in Italy and in the Mediterranean
in the past 40 years, in terms of the number of involved
fault splays, in a normal faulting earthquake context.

The earthquake ruptured mapped faults and (subor-
dinately) previously unknown fault strands of different
fault systems for a total cumulative surface rupture
length of about 46 km, when all strands of the surface
ruptures related to the three mainshocks of the
sequence are considered (see Main Map). The struc-
tural pattern and kinematics of the coseismic ruptures
appear to be independent of morphology and lithology,
affecting both bedrock and different bodies of uncon-
solidated deposits (Figures 2 and 3). This resulted in
primary surface faulting with a dominant strike of
N135°-160° (SW-dipping) and a subordinate strike of
N320°-345° (NE-dipping) in very good agreement
with the long-term surface expression of the VBFS
and with seismological data (Chiaraluce et al., 2017).
The large-scale deformation zone of the VBFS at the
surface ranges from 70 to 3200 m in width (distance
between fault splays), while the width of each displace-
ment zone (single fault splay) ranges from 3 to 60 m
 dista nces between overlapping or en echelon ruptures).
The average coseismic throw derived from all the
mapped ruptures is ~0.3 m; notably, more than 2 km
of these ruptures display >1 m average throw, with
maxima of ~2.4–2.6 m along the so-called Cordone
del Vettore fault scarp (Villani et al., 2018).

This map is based on two very dense datasets of
photographs and field measurements (taken on average
every ca.10 m), and as a result probably represents so
far the most detailed and comprehensive collection of
ground-surface fault rupture characteristics of any
earthquake in Italy, and one of the richest documenta-
tions of earthquake surface ruptures worldwide (e.g.
DeLong et al., 2016; Fletcher et al., 2014; Stirling
et al., 2017). From a methodological perspective, a
combined approach integrating remote surveys and
field reconnaissance proved to be effective in mapping
the extent and details of the surface ruptures even in
limited accessibility or dangerous areas.
<figure><img src="image_25.png" /></figure>

By providing a detailed map of the coseismic ruptures at the surface, the Main Map helps in understanding how slip is distributed at surface among the different fault splays thus resulting in a valuable contribution to surface faulting hazard assessment to better anticipate the potential location of future ruptures. In fact, the marked variability in the width of the rupture zone at surface observed for the 30 October 2016 M<sub>w</sub> 6.5 Norcia earthquake, as well as for other recent earthquakes (e.g. 2010 M<sub>w</sub> 7.2 El Mayor-Cucapah earthquake - Teran et al., 2015), has important implications in terms of support to decision makers for siting and designing facilities to be constructed in the vicinity of active faults (Boncio, Galli, Naso, & Pizzi, 2012). The results of this work represent also an important implementation to the worldwide database of earthquake surface ruptures (SURE, INQUA project 2016-2019). As a consequence, the presented data are valuable to enlarge the dataset used for the calculation of the empirical relationships applied to estimate the magnitude of paleo-earthquakes and the surface faulting hazard, which suffer to be based on a limited number of case studies (Stirling et al., 2013; Wesnousky, 2008).

Finally, this enormous collaborative experience has a twofold relevance: on the one side, it allowed for accurate and rich documentation of the earthquake ruptures before their deterioration; on the other hand, it represents the first large European survey of coseismic surface effects. In conclusion, we should use the Open EMERGEO Working Group experience as a leading example in order to establish, at the Euro-Mediterranean scale, geological survey teams who are prepared to respond rapidly to future seismic crises.

## Software

Most of the field surveying of the coseismic effects at the surface (type of observation, strike, vertical dislocation, fracture opening, etc.) was performed using the Rocklogger® Android App for mobile devices. The data collected in the field have been managed and stored in a georeferenced database using Esri ArcGIS 10.5 and Google Earth Pro. The pictures taken during the aerial surveys have been organized and edited with Adobe Photoshop Lightroom 6.4. Adobe Illustrator CS6 was used for final map production.

## Acknowledgements

We thank the Italian Civil Protection Department for the logistics. We are grateful to Corpo Nazionale dei Vigili del Fuoco (National Fire Corps) and Corpo Forestale dello Stato (State Forestry Corp) for the support on the aerial surveys; we also thank Corpo Nazionale Soccorso Alpino e Speleologico (Mountain Rescue) for the logistic support. We are grateful to the Editor and Associated Editor for the editorial handling. Juliane Cron, Mark Williamson Stirling and Christopher Milliner provided thoughtful comments that greatly

improved the early version of this manuscript and of the Main Map. Digital cartographic elements of the Carta Tecnica Regionale 1:10,000 scale by courtesy of Regione Umbria and Regione Marche. We acknowledge ESA CEOS seismic pilot program and CNES for their prompt response in providing us with Pleiades satellite images of the epicentral area.

## Disclosure statement

No potential conflict of interest was reported by the authors.

## Funding

We thank the Italian Civil Protection Department for funding. Z. K. Mildon was funded by NERC Studentship NE/L501700/1. The UK team was supported by NERC Urgency grants NE/P018858/1 and NE/P01660X/1, and NERC Standard grant NE/I02318X/1.

## ORCID

R. Civico http://orcid.org/0000-0002-5015-2155

S. Pucci http://orcid.org/0000-0002-3557-2936

F. Villani http://orcid.org/0000-0001-7133-0136

L. Pizzimenti http://orcid.org/0000-0003-1495-8175

P. M. De Martini http://orcid.org/0000-0002-3598-5191

R. Nappi http://orcid.org/0000-0002-1552-4398

## References

Amato, A., Azzara, R., Chiarabba, C., Cimini, G. B., Cocco, M., Di Bona, M., ... Ripepe, M. (1998). The 1997 Umbria-Marche seismic sequence: A first look at the main shocks and aftershocks. *Geophysical Research Letters*. doi:10.1029/98GL51842

Aringoli, D., Farabollini, P., Giacopetti, M., Materazzi, M., Paggi, S., Pambianchi, G., ... Tondi, E. (2016). The August 24th 2016 Accumoli earthquake: Surface faulting and deep-seated gravitational slope deformation (DSGSD) in the Monte Vettore area. *Annals of Geophysics*, 59(5), doi:10.4401/ag-7199

Barchi, M., Galadini, F., Lavecchia, G., Messina, P., Michetti, A. M., Peruzza, ... Vittori, E. (Eds.) (2000). *Sintesi delle conoscenze sulle faglie attive in Italia Centrale: parametrizzazione ai fini della caratterizzazione della pericolosità sismica* (pp. 62). Roma: GNDT, Gruppo Nazionale per la Difesa dai Terremoti, spec. publ.

Basili, R., Bosi, V., Galadini, F., Galli, P., Meghraoui, M., Messina, P., ... Sposato, A. (1998). The Colfiorito earthquake sequence of September-October 1997: Surface breaks and seismotectonic implications for the central Apennines (Italy). *Journal of Earthquake Engineering*, 2, 291-302.

Bendia, F., Giorandi, P., Pasquini, G., Teloni, R., Volatili, T., & Zambrano, M. (2017). Coseismic ruptures related to the 2016 Central Italy earthquake sequence in the northern termination of the Mt. Vettore-Mt. Bove fault system. In: *From 1997 to 2016: Three destructive earthquakes along the central Apennine fault system, Italy. Program and Abstracts* (p. 10). University of Camerino, International Field Trip, 19-22 July 2017. Retrieved from http://convegni.unicam.it/sites/d7.unicam.it.convegni/files/tde/ProgramandAbstract_HR18.42.pdf

Bernard, P., & Zollo, A. (1989). The Irpinia (Italy) 1980 earthquake: Detailed analysis of a complex normal
<figure><img src="image_26.png" /></figure>

faulting. *Journal of Geophysical Research*, **94**(B2), 1631–1647. doi:10.1029/ JB094iB02p01631

Bonzio, P., Galli, P., Naso, G., & Pizzi, A. (2012). Zoning surface rupture hazard along normal faults: Insight from the 2009 Mw 6.3 L'Aquila, Central Italy, earthquake and other global earthquakes. *Bulletin of the Seismological Society of America*, **102**(3), 918–935. doi:10.1785/0120100301

Bonzio, P., & Lavecchia, G. (2000). A geological model for the Colfiorito earthquakes (September-October 1997, central Italy). *Journal of Seismology*, **4**, 345–356.

Bonzio, P., Lavecchia, G., Milana, G., & Rozzi, B. (2004). Seismogenesis in Central Apennines, Italy: An integrated analysis of minor earthquake sequences and structural data in the Amatrice-Campotosto area. *Annals of Geophysics*, **47**, 1723–1742.

Bonzio, P., Pizzi, A., Brozzetti, F., Pomposo, G., Lavecchia, G., Di Naccio, D., & Ferrarini, F. (2010). Coseismic ground deformation of the 6 April 2009 L'Aquila earthquake (central Italy, Mw6.3). *Geophysical Research Letters*, **37**, L06308. doi:10.1029/2010GL042807

Brozzetti, F., & Lavecchia, G. (1994). Seismicity and related extensional stress field: The case of the Norcia Seismic Zone (central Italy). *Annales Tectonicae*, **8**, 36–57.

Calamita, F., & Pizzi, A. (1992). Tettonica quaternaria nella dorsale appenninica umbro-marchigiana e bacini intrapenninici associati. *Studi Geologici Camerti*, **1992/1**, 17–25.

Calamita, F., & Pizzi, A. (1994). Recent and active extensional tectonics in the southern Umbro-Marchean Apennines (central Italy). *Mem. Soc. Geol. It.*, **48**, 541–548.

Calamita, F., Pizzi, A., & Roscioni, M. (1992). I fasci di faglie recenti ed attive di M. Vettore – M. Bove e di M. Castello – M. Cardosa (appennino Umbro-Marchigiano). *Studi Geologici Camerti*, **1992/1**, 81–95.

Carafa, M. M. C., & Bird, P. (2016). Improving deformation models by discounting transient signals in geodetic data: 2. Geodetic data, stress directions, and long-term strain rates in Italy. *Journal of Geophysical Research: Solid Earth*, **121**, 5557–5575. doi:10.1002/2016JB013038

Carminati, E., & Doglioni, C. (2012). Alps vs. Apennines: The paradigm of a tectonically asymmetric earth. *Earth-Science Reviews*, **112**(1–2), 67–96. ISSN 0012-8252. doi:10.1016/j.earscirev.2012.02.004

Cello, G., Deiana, G., Ferelli, L., Marchegiani, L., Maschio, L., Mazzoli, S., ... Vittori, T. (2000). Geological constraints for earthquake faulting studies in the Colfiorito area (central Italy). *Journal of Seismology*, **4**, 357–364.

Cello, G., Mazzoli, S., Tondi, E., & Turco, E. (1997). Active tectonics in the central Apennines and possible implications for seismic hazard analysis in peninsular Italy. *Tectonophysics*, **272**(1), 43–68. ISSN 0040-1951. doi:10.1016/S0040-1951(96)00275-2

Centamore, E., Adamoli, L., Berti, D., Bigi, S., Casnedi, R., Cantalamessa, G., ... Potetti, M. (1992). *Carta geologica dei bacini della Laga e del Cellino e dei rilievi carbonatici cir costanti, in Studi Geologici Camerti, Vol. Spec*. Firenze: Università degli Studi, Dipartimento di Scienze della Terra, SELCA.

Chiarabba, C., & Chiodini, G. (2013). Continental delamination and mantle dynamics drive topography, extension and fluid discharge in the Apennines. *Geology*, **41**(6), 715–718. doi:10.1130/G33992.1

Chiaraluce, L., Valoroso, L., Piccinini, D., Di Stefano, R. & De Gori, P. (2011). The anatomy of the 2009 L'Aquila normal fault system (central Italy) imaged by high resolution foreshock and aftershock locations. *J. Geophys. Res.*, **116**, B12311, doi:10.1029/2011JB008352.

Chiaraluce, L., Di Stefano, R., Tinti, E., Scognamiglio, L., Michele, M., Casarotti, E., ... Marzorati, S. (2017). The 2016 central Italy seismic sequence: A first look at the mainshocks, aftershocks, and source models. *Seismological Research Letters*, **88**(3), 757–771. doi:10.1785/0220160221

Cinti, F. R., Cucci, L., Marra, F., & Montone, P. (1999). The 1997 Umbria-Marche (Italy) earthquake sequence: Relationship between ground deformation and seismic structure. *Geophysical Research Letters*, **26**, 895–898. doi:10.1029/1999GL900142

Civico, R., Blumetti, A. M., Chiarini, E., Cinti, F. R., La Posta, E., Papasodaro, F. ... Pantosti, D. (2016). Traces of the active Capitignano and San Giovanni faults (Abruzzi Apennines, Italy). *Journal of Maps*, **12**, 453–459. doi:10.1080/17445647.2016.1239229

D'Agostino, N. (2014). Complete seismic release of tectonic strain and earthquake recurrence in the Apennines (Italy). *Geophysical Research Letters*, **41**, 1155–1162. doi:10.1002/2014GL059230

D'Agostino, N., Jackson, J., Dramis, F., & Funiciello, R. (2001). Interactions between mantle upwelling, drainage evolution and active normal faulting: An example from the central Apennines (Italy). *Geophysical Journal International*, **147**(2001), 475–497. doi:10.1046/j.1365-246X.2001.00539.x

DeLong, S. B., Donnellan, A., Ponti, D. J., Rubin, R. S., Lienkaemper, J. J., Prentice, C. S., ... Parker, J. W. (2016). Tearing the terroir: Details and implications of surface rupture and deformation from the 24 August 2014 M6.0 South Napa earthquake, California. *Earth and Space Science*, **3**, 416–430. doi:10.1002/2016EA000176

Deschamps, A., Iannaccone, G., & Scarpa, R. (1984). The Umbrian earthquake of 19 September 1979. *Annals of Geophysics.*, **2**(1), 29–36.

EMERGEO Working Group. (2010). Evidence for surface rupture associated with the Mw 6.3 L'Aquila earthquake sequence of April 2009 (central Italy). *Terra Nova*, **22**(1), 43–51. doi:10.1111/j.1365-3121.2009.00915.x

EMERGEO Working Group. (2012). Technologies and new approaches used by the INGV EMERGEO Working Group for real time data sourcing and processing during the Emilia Romagna (northern Italy) 2012 earthquake sequence. *Annals of Geophysics*, **55**(4), 2012. doi:10.4401/ag-6117

EMERGEO Working Group. (2016). Coseismic effects of the 2016 Amatrice seismic sequence: First geological results. *Annals of Geophysics*, **59**(5), doi:10.4401/ag-7195

Ferrarini, F., Lavecchia, G., de Nardis, R., & Brozzetti, F. (2014). Fault geometry and active stress from earthquakes and field geology data analysis: The Colfiorito 1997 and L'Aquila 2009 cases (central Italy). *Pure and Applied Geophysics*, doi:10.1007/s00024-014-0931-7

Fletcher, J. M., Teran, O. J., Rockwell, T. K., Oskin, M. E., Hudnut, K. W., Mueller, K. J., ... González-García, J. (2014). Assembly of a large earthquake from a complex fault system: Surface rupture kinematics of the April 4, 2010 El Mayor–Cucapah Mw7.2 earthquake. *Geosphere*, **10**, 797–827. doi:10.1130/GES00933.1

Galadini, F., & Galli, P. (1999). The Holocene paleoearthquakes on the 1915 Avezzano earthquake faults (central Italy): implications for active tectonics in the central Apennines. *Tectonophysics*, **308**(1), 143–170. doi:10.1016/S0040-1951(99)00091-8

Galadini, F. & Galli, P. (2000). Active Tectonics in the Central Apennines (Italy) – Input Data for Seismic
<figure><img src="image_27.png" /></figure>

Hazard Assessment. *Natural Hazards* 22: 225. doi:10.1023/A:1008149531980

Galadini, F., & Galli, P. (2003). Paleoseismology of silent faults in the Central Apennines (Italy): the Mt. Vettore and Laga Mts. Faults. *Annals of Geophysics*, *46*(5), 815–836. doi:10.4401/ag-3457

Galli, P., Galadini, F., & Calzoni, F. (2005). Surface faulting in Norcia (central Italy): A “paleoseismological perspective”. *Tectonophysics*, *403*, 117–130.

Galli, P., Galadini, F., & Pantosti, D. (2008). Twenty years of paleoseismology in Italy. *Earth-Science Reviews*, *88*, 89–117. doi:10.1016/j.earscirev.2008.01.001

Herrmann, R. B., Malagnini, L., & Munafò, I. (2011). Regional moment tensors of the 2009 L'Aquila earthquake sequence. *Bulletin of the Seismological Society of America*, *101*, 975–993. doi:10.1785/0120100184

Lavecchia, G., Brozzetti, F., Barchi, M., Menichetti, M., & Keller, J. V. A. (1994). Seismotectonic zoning in east-central Italy deduced from an analysis of the Neogene to present deformations and related stress fields. *Geological Society of America Bulletin*, *106*, 1107–1120.

Lavecchia, G., Castaldo, R., de Nardis, R., De Novellis, V., Ferrarini, F., Pepe, S., ... Tizzani, P. (2016). Ground deformation and source geometry of the 24 August 2016 Amatrice earthquake (central Italy) investigated through analytical and numerical modeling of DINSAR measurements and structural-geological data. *Geophysical Research Letters*, *43*, 12389–12398. doi:10.1002/2016GL071723

Lavecchia, G., Ferrarini, F., Brozzetti, F., de Nardis, R., Boncio, P., & Chiaraluce, L. (2012). From surface geology to aftershock analysis: Constraints on the geometry of the L'Aquila 2009 seismogenic fault system. *It. Journ. Geosciences*, *131*, 330–347. doi:10.3301/IJG.2012.24

Livio, F., Michetti, A. M., Vittori, E., Gregory, L., Wedmore, L., Piccardi, L., ... Central Italy Earthquake, W. G. (2016). Surface faulting during the August 24, 2016, central Italy earthquake (Mw 6.0): preliminary results. *Annals of Geophysics*, *59*(5). doi:10.4401/ag-7197

Michetti, A. M., Brunamonte, F., Serva, L., & Vittori, E. (1996). Trench investigations of the 1915 Fucino earthquake fault scarps (Abruzzo, Central Italy): Geological evidence of large historical events. *Journal of Geophysical Research: Solid Earth*, *101*(B3), 5921–5936.

Mildon, Z. K., Roberts, G. P., Faure Walker, J. P., Wedmore, L., & McCaffrey, K. J. W. (2016). Active normal faulting during the 1997 seismic sequence in Colfiorito, Umbria: Did slip propagate to the surface? *Journal of Structural Geology*, *91*, 102–113. doi:10.1016/j.jsg.2016.08.011

Oddone, E. (1915). Gli elementi fisici del grande terremoto marsicano-fucense del 13 gennaio 1915. *Bollettino Della Società Sismologica Italiana*, *19*, 71–216.

Pantosti, D., & Valensise, G. (1990). Faulting mechanism and complexity of the November 23, 1980, Campania-Lucania earthquake, inferred from surface observations. *Journal of Geophysical Research*, *95*(B10), 15319–15341. doi:10.1029/JB095iB10p15319

Pierantoni, P., Deiana, G., & Galdenzi, S. (2013). Stratigraphic and structural features of the Sibillini Mountains (Umbria-Marche Apennines, Italy), Italy. *Journal of Geosciences*, *132*(3), 497–520. doi:10.3301/IJG.2013.08

Pizzi, A., Calamita, F., Coltorti, M., & Pieruccini, P. (2002). Quaternary normal faults, intramontane basins and seismicity in the Umbria-Marche-Abruzzi Apennine Ridge (Italy): contribution of neotectonic analysis to seismic hazard assessment. *Bollettino della Società Geologica Italiana* (Spec. 1), 923–929.

Pucci, S., De Martini, P. M., Civico, R., Villani, F., Nappi, R., Ricci, T., ... Pantosti, D. (2017). Coseismic ruptures of the 24 August 2016, Mw 6.0 Amatrice earthquake (central Italy). *Geophysical Research Letters*, *44*, doi:10.1002/2016GL071859

Rovida, A., Locati, M., Camassi, R., Lolli, B., & Gasperini, P. (Eds.) (2016). *CPTI15, the 2015 version of the parametric catalogue of Italian earthquakes*. Rome: Istituto Nazionale di Geofisica e Vulcanologia. doi:10.6092/INGV.IT-CPTI15

Serva, L., Blumetti, A. M., & Michetti, A. M. (1988). Gli effetti sul terreno del terremoto del Fucino (13/1/1915); tentativo di interpretazione della evoluzione tettonica recente di alcune strutture. *Mem. Soc. Geol. It.*, 35, 893–907.

Stirling, M. W., Goded, T., Berryman, K., & Litchfield, N. J. (2013). Selection of earthquake scaling relationships for seismic-hazard analysis. *Bulletin of the Seismological Society of America*, *103*(6), 2993–3011. doi:10.1785/0120130052

Stirling, M. W., Litchfield, N. J., Villamor, P., Van Dissen, R. J., Nicol, A., Pettinga, J., ... Zinke, R. (2017, June). The M<sub>w</sub>7.8 2016 Kaikōura earthquake: Surface fault rupture and seismic hazard context. *Bulletin of the New Zealand Society for Earthquake Engineering*, *50*(2), 73–84.

Tarquini, S., Isola, I., Favalli, M., Mazzarini, F., Bisson, M., Pareschi, M. T., & Boschi, E. (2007). Tintaly/01: A new triangular irregular network of Italy. *Annals of Geophysics*, *50*, 407–425. doi:10.4401/ag-4424

Teran, O. J., Fletcher, J. M., Oskin, M. E., Rockwell, T. K., Hudnut, K. W., Spelz, R. M., ... Morelan, A. E. (2015). Geologic and structural controls on rupture zone fabric: A field-based study of the 2010 Mw 7.2 El Mayor-Cucapah earthquake surface rupture. *Geosphere*, *11*(3), 899–920. doi:10.1130/GES01078.1

Vai, G. B., & Martini, L. P. (Eds.). (2001). *Anatomy of an Orogen: The Apennines and adjacent Mediterranean basins* (pp. 633). Dordrecht: Kluwer Academic.

Valoroso, L., Chiaraluce, L., Piccinini, D., Di Stefano, R., Schaff, D., & Waldhauser, F. (2013). Radiography of a normal fault system by 64,000 high-precision earthquake locations: The 2009 L'Aquila (central Italy) case study. *J. Geophys. Res. Solid Earth*, *118*, 1156–1176. doi:10.1002/jgrb.50130

Villani, F., Civico, R., Pucci, S., Pizzimenti, L., Nappi, R., De Martini, P.M., & the Open EMERGEO Working Group (2018). A database of the coseismic effects following the 30 October 2016 Norcia earthquake in Central Italy. *Scientific Data*, doi:10.1038/sdata.2018.49.

Vittori, E., Di Manna, P., Blumetti, A. M., Comerci, V., Guerrieri, L., Esposito, E., ... Cowie, P. A. (2011). Surface faulting of the 6 April 2009 Mw 6.3 L'Aquila earthquake in central Italy. *Bulletin of the Seismological Society of America*, *101*(4), 1507–1530. doi:10.1785/0120100140

Wesnousky, S. G. (2008). Displacement and geometrical characteristics of earthquake surface ruptures: Issues and implications for seismic-hazard analysis and the process of earthquake rupture. *Bulletin of the Seismological Society of America*, *98*, 1609–1632. doi:10.1785/0120070111

Westaway, R., & Jackson, J. (1984). Surface faulting in the southern Italy Campania-Basilicata earthquake of 23 November 1980. *Nature*, *312*, 436–438.

Westaway, R., & Jackson, J. (1987). The earthquake of the 1980 November 23 in Campania-Basilicata (southern Italy). *Geophysical Journal International*, *90*(2), 375–443. doi:10.1111/j.1365-246X.1987.tb00733.x