Geophysical Journal InternationalGeophys. J. Int. (2014) doi: 10.1093/gji/ggu116

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Reply to ‘Comments on the paper “Are the source modelsof the M 7.1 1908 Messina Straits earthquake reliable?Insights from a novel inversion and sensitivity analysisof levelling data” by Aloisi et al. (2012)’

M. Aloisi,1 V. Bruno,1 F. Cannavo,1 L. Ferranti,2 M. Mattia1 and C. Monaco3

1Istituto Nazionale Geofisica e Vulcanologia - Osservatorio Etneo, I-95125 Catania, Italy. E-mail: aloisi@ct.ingv.it2Dipartimento di Scienze della Terra, dell’Ambiente e delle Risorse DiSTAR, Universita degli Studi di Napoli Federico II, Napoli, Italy3Dipartimento di Scienze Biologiche, Geologiche e Ambientali, Universita degli Studi di Catania, Catania, Italy

Accepted 2014 March 25. Received 2014 March 24; in original form 2014 February 12

S U M M A R YWe reply to the comments of De Natale and Pino (2013) on the paper ‘Are the source modelsof the M 7.1 1908 Messina Straits earthquake reliable? Insights from a novel inversion andsensitivity analysis of levelling data’ by Aloisi et al. (2012, Geophys. J. Int., 192, 1025–1041). We entirely reject their speculative comments and confirm our viewpoint about theimpossibility of discriminating between the two oppositely dipping fault models on the basisof the levelling data alone; we state again that their role as a keystone for modellers is untenable.The comments of De Natale and Pino (2013) are welcomed insofar they give us the possibilityto improve our previous analysis, and to criticize the mainstream hypothesis favouring to alow-angle East dipping fault in the Sicilian side of the Messina Straits as responsible of the1908 destructive earthquake.

Key words: Transient deformation; Earthquake dynamics; Earthquake source observations.

1 I N T RO D U C T I O N

We acknowledge the comments by and Pino & De Natale (2014,from now on P14), to our work on the source model of the 1908Messina Straits earthquake (Aloisi et al. 2012, from now on A13),because they stimulate us to clarify some fundamental aspects ofour research. We recall that the paper was aimed to define limits andusefulness of levelling data collected more than 100 yr ago. For thispurpose, we carried out a novel inversion of the original data col-lected by Loperfido (1909) as we retain that the ongoing debate onthe source, highlights potential pitfalls in the use of levelling dataas model constraints. In our opinion, indeed, seismogenic sourcemodels derived from old geophysical or geodetic data must be cor-roborated by geological data, otherwise any attempt to retrieve arealistic interpretation can be affected by wrong assumption and,consequently, lead to wrong final products. However, contrary towhat is stated by the authors in their comments, we do not offera unique solution: our analysis highlights that there is no model,among those proposed so far, which is able to explain the availabledata, and the data themselves are not able to constrain a modelsolution.

We think that the authors have missed to take some of our ba-sic methodological statement, particularly regarding the concept ofdata integration. In fact, in the ‘Summary’ they write: ‘Moreover,especially when dealing with such old events and data, we consider

that it is more prudent not to derive conclusions on the basis of a sin-gle data set, as all of the available information should be included inany interpretation.’ This is precisely what we did, because we basedour analysis on integration of geodetic, structural and geomorpho-logical data set. In the following, we reply to the comments pointingout that in our approach we have tried to analyse the geodetic datacollected by Loperfido (1909) in their geological context.

2 G E O D E T I C DATA A N D A NA LY T I C A LI N V E R S I O N S

Before analysing the geodetic data collected by IGM (IstitutoGeografico Militare) in 1909, we critically read the report ofLoperfido (1909). He clearly affirms that many of the benchmarksmeasured during the 1909 levelling survey are affected by land-slides, due to coupled effects of the devastating earthquake, ofthe tsunami wave and to the ground lithology where some of thebenchmarks were installed. Loperfido also remarked the need ofmeasuring the large horizontal displacements induced by landslidesall along the levelling route. Furthermore, the study of De Stefani(1910) seriously warns about the risk of using the levelling mea-surements performed after the 1908 earthquake to draw geologicalconclusions. De Stefani, one of the most important Italian geol-ogist between the 19th and 20th century, among the founders of

C© The Authors 2014. Published by Oxford University Press on behalf of The Royal Astronomical Society. 1

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the Italian Geological Society and President of the same Societyin 1896, affirmed that, although the measurements were performedaccurately by IGM, most of the levelling benchmarks were placed:(1) along railways or carriage roads that, due to incoherent mate-rials (crushed stones) used for their foundations, were not suitableto measure ground changes caused by coseismic displacement, be-cause of subsidence related to shacking or to continuous transit oftrains or heavy vehicles; (2) on light parapets that were subject toaccidental crushes or to tilt for many reasons and (3) on bridges,buildings or houses exposed to damages, collapses or displacementsfor the violent earth shacking occurred during the 1908 event. Healso warned the users of Loperfido (1909) levelling data for geodeticreasons related to the starting points of both levelling routes. More-over, he reminded that the levelling route in the Sicilian side of theMessina Straits was completed in 1898, and the benchmarks mighthave been affected by displacements caused by the 1905 September8 (Mw = 7; Rovida et al. 2011) earthquake in Southern Calabria.

According to these technical remarks, we suspect that the level-ling data are not thoroughly reliable to model the seismogenic fault.Thus, our aim was to verify if the levelling data could neverthelesshold a meaningful signal able to discriminate between different tec-tonic sources. In this sense, we now want to define the limits of thelevelling data and reopen the debate about this important argumentincluding morphotectonic, geophysical and geodetic observationsthat were presented by A13.

Before discussing the criticisms raised by P14 about the choiceswe made to model the seismogenic fault and the statistical analysiswe performed to compare different models, we want to reply to theircomments about the data from a ‘physical point of view.’

P14 state that the zones of maximum subsidence correspond tothe three promontories that are the sites of the western-most level-ling points on the Calabrian coast and that, considering the verticaldeformation field shown in fig. 4 of A13 it implies that these bench-marks are points of minimum distance from the fault. Hence, thedeformation pattern should be consistent with a fault located west-wards with respect to the Calabrian coast. We believe that theseobservations cannot exclude faults located on the Calabrian side ofthe Straits. In fact, considering the observations done by De Stefani(1910) soon after the 1908 event along the levelling route measuredby Loperfido (1909), the benchmarks that show the maximum sub-sidence (and that are considered by P14 to exclude the hypothesis offaults located on the Calabrian side of the Straits) were installed incollapsed or damaged buildings. In detail, as shown in Fig. 1, thesebenchmarks were located (1) in Villa San Giovanni, in the Imma-colata church that was ruined and on light parapets; (2) in ReggioCalabria, in the Saint Lucia church, Palazzo Municipale, Garibaldimemorial and in the cathedral that collapsed or were damaged, orSouth of Reggio Calabria, along a little bridge near the railway and(3) near the Pellaro station, that was completely razed to the ground.

Furthermore, we retain wrong that the benchmarks of the har-bour of Messina can be used during the analytical inversion. In fact,many reports (Baratta 1910; Rizzo 1910) described this area asdevastated by the 1908 events, because strong liquefaction affectedthe sands filling the Messina natural harbour and gravitational col-lapses occurred where docks and benchmarks were located (see mapand photographs in Fig. 2). So, in contrast with P14, we hold thatthe large elevation variations measured on benchmarks of Messinaharbour are unusable.

We consider incongruous the following comment: ‘In A13, thereare also questionable and confusing choices made. On the one hand,they tested a Sicilian source with the dip fixed at 60◦, when it is clearthat this kind of model must have a low angle to fit the data.’ In this

statement the authors show a serious prejudice since they decide inadvance that the fault must be low angle, contrary to all the geolog-ical observations in the Straits. We used an open-minded approachin that we preferred to firstly perform an unconstrained inversionof the data, followed by a further inversion with a 60◦ constraineddip of east-dipping and west-dipping planes, as suggested by me-chanical models and field observations (see below). Moreover, theauthors omit to comment that our inversion performed by constrain-ing the dip of an east-dipping plane to 60◦ resulted in a normal faultvery close the Calabrian side of the Straits, not compatible with thegeological framework.

As concerns the inversion of levelling data we want to stress thata mere statistical test without comparison with geological data canlead to unrealistic interpretations. Published geological data suggestus to exclude a low-angle fault (e.g. Ghisetti 1984, 1992; Tortoriciet al. 1995; Monaco & Tortorici 2000; Ferranti et al. 2007, 2008;Argnani et al. 2009; Scarfi’ et al. 2009; D’Amico et al. 2010a,2011). Thus, in Aloisi et al. (2012), we also chose to constrainthe fault dip parameter to the most likely value in inverting thelevelling data. We found a solution that minimize the WRMSE(i.e. Sicilian source dip-fixed) and compared this mathematicallyglobal and constrained optimum model with a west-dipping modelcorresponding to the Armo fault (i.e. Calabrian source dip-fixed).

For this reply, as suggested by P14, we performed the statisticalcomparison by using the ‘simple and powerful’ Fisher’s test onresidue variances. We tested the two sets of residuals coming fromthe two dip-fixed sources for the null hypothesis H0 that they havethe same variance against the alternative hypothesis (H1) that theyhave different variance. For the n = 110 degrees of freedom (i.e.the measurements) and the commonly adopted significance level ofα = 5 per cent we have a limit value for the Fisher-distribution ofF−1

1− α2 ;n−1;n−1 = 1.4560. Our analysis results in a ratio of sampled

variances of 1.4366, thus the null hypothesis cannot be rejected evenif the two compared models are different. This result, together withthe other indexes reported in A13, corroborates the idea that thelevelling data, without considering benchmark instability and theirdoubtful application for fault modelling, are also not definitive infault identification.

3 S E I S M O L O G I C A L DATA

P14 state that ‘Indeed, when the joint results of the seismologicaland geodetic analyses are taken into account, a consistent and robustsource model can be derived that indicates that a low angle, east-dipping fault is the most likely source of the 1908 Messina Straitsearthquake’. We are puzzled by this apodictically formulated state-ment about the reliability of both geodetic and seismic data. Wehave already demonstrated that there are many doubts about theuncritical use of geodetic data, and now we submit to the attentionof the reader some statements found in literature about the originalseismic data collected during the 1908 earthquake and the derivedanalysis:

(1) From Pino et al. (2000): ‘Besides, some of the stations arealmost nodal, and the polarity is not always clear. Because of thepoor azimuthal and distance coverage of the usable waveforms it isnot possible to obtain an unambiguous discrimination between thedifferent solutions of Fig. 2’. In Fig. 2 the authors propose the focalmechanisms for the 1908 Messina Straits earthquake as determinedby six different authors.

(2) Always from Pino et al. (2000): ‘With the assumption ofa realistic rupture propagation velocity we determined the slip

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Figure 1. Redrawn from Aloisi et al. (2012). Seismotectonic setting of the Messina Straits region. Faults (thick solid lines barbed on the downthrown side,dashed where inferred or submerged) after Ghisetti (1992), Monaco & Tortorici (2000), Jacques et al. (2001), Ferranti et al. (2007), Argnani et al. (2009):ARF, Armo Fault; CF, Cittanova Fault; MSGF, Motta San Giovanni Fault; RCF, Reggio Calabria Fault; SCF, Southern Calabria Fault; SEF, S. Eufemia Fault;SF, Scilla Fault. The levelling data of Loperfido (1909) are reported as yellow circles. Green circles placed along the three promontories are the sites of thewestern-most levelling points on the Calabrian coast. According to De Stefani (1910) these benchmarks were strongly affected by ground shacking induced bythe 1908 event.

distribution. Because of the poor azimuthal and distance cover-age, we could not determine a focal mechanism, nor discriminatebetween the published solutions which generally display only minordifferences’.For the sake of clarity, the azimuthal coverage of the recordingpoints (except for one among the 6 used stations) spans from 12◦ to16◦ and the minimum distance of the recording station is 1000 km.The seismic data from stations closer to Messina and Reggio wereunusable because the limited dynamic range produced waveformsseverely saturated and distorted.

(3) From Amoruso et al. (2002): ‘The 1908 Messina earthquakewas recorded by 110 seismographic stations around the world (Rizzo1910). Since it occurred before a global homogeneous network wasorganized and installed, ‘seismological data are far from being pre-cise, and many original records are no longer available. As a con-sequence seismological analyses have to rely mostly upon polaritydeterminations dating back to that period, and the focal mechanism

is not well constrained because of the poor coverage of the focalsphere by the stations for which data are available’.

Moreover, in general, finite fault inversions using seismologicaldata could be not completely reliable because of several assump-tions (e.g. D’Amico et al. 2010b; Koper et al. 2012; Sufri et al.2012). In fact, the method requires knowledge of the fault planeand the moment tensor solution. For these reasons, the problemis highly underdetermined and requires constraints and dampingwhich can bias the result and often there is a strong trade-off be-tween rupture length and velocity, though rupture duration could beconstrained.

Finally, in our opinion the seismological data, although usefulfor a generic determination of the main parameters of the causativefault of the 1908 earthquake, should be used with a precautionaryapproach with respect to the one proposed by P14 and works citedthere. Furthermore, we retain that it is impossible to obtain a robust

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Figure 2. Top, map of the Messina natural harbour showing collapsed sectors inside (dark areas) and ground fractures (small lines parallel to the coastline).Bottom, photographs showing the collapsed docks where benchmarks were located.

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source model even with the joint results of the seismological andgeodetic analyses.

4 I N S I G H T S F RO M S T RU C T U R A L A N DG E O M O R P H O L O G I C A L DATA

P14 states: ‘On these grounds, and based on geological consider-ations, they argued in favour of the Armo fault – a high-angledstructure on the Calabrian side of the Messina Straits – as respon-sible for the this 1908 earthquake’. This statement is only in parttrue and deserves a more careful reading. We simply stated thatour ‘result contradicts the conventional conclusion that the geode-tic data favour the latter (the east-dipping fault as the most likelysource), and places another possible candidate seismogenic sourceof the 1908 earthquake near to the Armo Fault’. In other words, wedo not use, like many previous authors before including P14, thegeodetical or seismological data to propose a causative fault, butlook into the geological record for the best candidate seismogenicsource. Our investigation pointed out the existence of west-dippinghigh-angle active faults on the one hand, and on the other handthe lack of east-dipping low-angle faults with evidence of activity.We take the opportunity from the P14 criticism to better clarify theresults of the geological review and new analysis.

A13 presented a documented activity of the Armo fault duringthe late Pleistocene and up to the Late Holocene (see the upliftedbeachrock on the fault footwall). Although, as commented by P14,we do not present clear evidence in support of reactivation of thisstructure during the 1908 earthquake, submerged archaeological re-mains on the hanging wall of the Motta San Giovanni fault couldbe an important indication of very recent tectonic mobility. More-over, the area of greatest damage was located in Calabria, alongthe outcropping master faults, where also subsidence and groundfractures were recorded after the event (e.g. Baratta 1910; Blumettiet al. 2008). As regards the Motta San Giovanni fault, P14 wronglyaffirms that it is NW–SE striking. Actually, it is a ∼N-S orientedsplay of the Armo fault, falling together very close to the modelledwest-dipping source.

However, we need to recall that the complex geology and higherosion rate in the on-land and submerged part of the Straits con-spire to mask any evidence of recent earthquake scarps, and socould be for the 1908 event. Bearing this in mind, we think moresignificant to give credit to a fault with evidence of repeated LateQuaternary deformation rather than fulfilling the likely impossi-ble task of searching evidence of improbable geodetically definedcausative fault for the 1908 earthquake.

As regards the latter task, the geological expression of a low-angleeastern-dipping faults has never been observed in seismic reflectionsurveys. Recent seismic profiles analysis (Argnani et al. 2009) ledto conclude that ‘It is worth noting that the faults inferred by inversemodelling (e.g. Amoruso et al. 2002 and reference therein) as re-sponsible for the 1908 earthquake do not show up on seismic data.In fact, the undisrupted and subparallel Plio-Quaternary strata seenon seismic profiles argue against the occurrence of active faults’.The fault criticized by Argnani et al. (2009) is the low angle east-dipping one on the Sicilian margin, considered by P14 as the onlyreliable source. In the same paper, the author show evidences offaulting on the Calabrian margin.

Moreover, Ridente et al. (2014) perform a morpho-bathymetricstudy of the Messina Strait and surroundings, investigated by meansof high-resolution swath bathymetry. In this paper the authors areskeptical about the possibility that a fault lying in the Messina Strait

could be considered as the causative source of the 1908 earthquakefor the ‘lack of clear evidence of seafloor rupture, as would havebeen expected in the case of a Mw 7.1 > 30 Km long fault’ andthis aspect, always following Ridente et al. (2014) ‘may indicatethat the source of the 1908 event was not a shallow one or that (incontrast with source modelling data) it is outside (likely south of)the Messina Strait area’. Another interesting result of the analysis ofRidente et al. (2014) is that ‘by assuming that geomorphic anoma-lies in the drainage patterns and clustering of slope failure maybe indicative of tectonic processes (superimposed on sedimentarydynamics), the Calabrian margin appears more actively deformedcompared to the Sicilian margin’. The morpho-batymetric analysisagrees with seismic profile data about the quite undisturbed strataon the Sicilian margin of the Strait, not compatible with the pres-ence of a 30–35-km-long active fault that should be responsible ofthe 1908 earthquake. The assumption that this fault should be blindis also not proven.

More in general, if such a strong earthquake was caused by alow-angle fault, features and fabrics related to active low-angledisplacement should be widespread in the region. However, LateQuaternary low-angle faults have not been mapped in the CalabrianArc (see also Ghisetti 1984, 1992; Tortorici et al. 1995; Monaco& Tortorici 2000; Jacques et al. 2001; Galli & Bosi 2002; Ferrantiet al. 2007, 2008) and in the southern Apennines (e.g. Papanikolaou& Roberts 2007).

P14 mention the topographic and morphological analysis per-formed by Valensise & Pantosti (1992), to support that ‘the presentstructure of the Straits is compatible with repeated 1908-like earth-quakes, with slip distributions similar to what was seen for thepublished east-dipping sources’. To prove this, Valensise & Pan-tosti (1992) claim that there is similarity between coseismic eleva-tion changes predicted by the low angle east-dipping 1908 sourcefault and the elevation of the inner edge of the Tyrrhenian terrace(125 ka). The similarity should be related to stationary long termactivity of this fault at average slip rate of 1.4 mm yr–1. This state-ment can be easily contradicted by the simple observation that afault, active since 125 ka with rates of 1.4 mm yr–1, would cause atleast 175 m of geological offset. Even a blind fault (such as the onesuggested by the authors) should be accompanied by passive fold-ing of the overlying sediments or recorded by seafloor morphology.We pointed out above that such signals have never been observed inseismic reflection or bathymetric surveys along the Sicilian marginof the Straits. Although the Valensise & Pantosti (1992) work hasprovided insights into understanding the relation between regionaluplift and local deformation sources (faults) in shaping the structureof the Messina Strait, no unambiguous evidence in support of theeast-dipping source can be taken from that paper. In fact, the patternof differential uplift of Pleistocene marine terraces is explained bywest-dipping faults as well (Ghisetti 1984, 1992).

As regards the tsunami (cited by P14 in support of a sourcelocated in the Strait), no agreement in the geological communityexists on its source. Actually, most of the recent papers retain thatan individual (Billi et al. 2008) or compound (Anita et al. 2012;Polonia et al. 2012; Ridente et al. 2014) submarine failure couldbe responsible for the 1908 tsunami generation. On this ground, theneed for having a submarine source is obviously released.

5 D I S C U S S I O N A N D C O N C LU S I O N S

We confirm that levelling data alone do not differentiate betweena west-dipping fault on the Calabrian side from an east-dippingfault on the Sicilian side of the Straits. However, we stress here

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that we do not bear conclusive evidence that the Armo fault andits unknown northern and southern (offshore) continuation werethe source of the 1908 event. Rather, our work was intended,once the reliability of Loperfido (1909) data is proved question-able for the unique definition of the seismogenic source location,to drive the research community toward the search of independent(geological or geophysical) evidence for a better model for the 1908event.

In summary, the main arguments that in our opinion should beconsidered for future investigations on the 1908 seismogenic sourceare:

(1) The levelling data collected by Loperfido are surely biasedby many factors such as: (i) secondary effects of the earthquake;(ii) choice of benchmarks involved, directly or not, in local effectsdue to liquefaction processes, landslides, collapses of edifices, poorchoice of benchmark’s pillar, etc. and (iii) geodetic reasons relatedto the starting points of both the levelling routes.

(2) Under the hypothesis that a tectonic signal attributable tothe source of the 1908 earthquake is present in the levelling data,we have demonstrated that the data itself do not contradict thepossibility that this structure lies on the Calabrian side of the Straitand, specifically, that it can be identified with the Armo fault.

(3) The Fisher test, suggested by P14, confirms the non-uniqueness of results of the analytical inversions, if realistic faultsare chosen.

(4) Seismological data suffer of the poor quality of the originalrecord. The polarities are often of doubtful quality and the arealcoverage of the few usable stations is very poor.

(5) The geological arguments (e.g. Valensise & Pantosti 1992)supporting the east-dipping low angle fault are very weak. We areskeptic about the possibility that a low-angle normal fault can beconsidered as realistic in the geological and seismo-tectonic frameof the Straits. Only the Calabrian side of the Straits has evidence ofactive normal faulting, among which the Armo fault (west-dippingat ∼60◦) show Late Pleistocene–Holocene evidence.

(6) Recent morphological and seismic published surveys of theStraits seafloor (and the surroundings areas) confirm that any ev-idence of the presence or of the effects of a 30–35-km-long faultable to generate a Mw 7.1 earthquake is totally absent on the Si-cilian margin, while evidence of tectonic activity is present on theCalabrian margin.

(7) The argument supported by P14 about the origin of thetsunami waves is highly questionable, in light of the recentlyfavoured hypotheses of tsunamigenic submarine landslides (Ridenteet al. 2014, with references).

The above arguments, only partially expressed by A13, point to theneed of more in-depth investigations, always starting from goodgeological assumptions, aimed to a real improvement of the seis-motectonic frame of the Messina Straits. This is necessary in lightof the design of new large infrastructures.

A C K N OW L E D G E M E N T S

The authors wish to thank Sebastiano D’Amico and Randy Kellerfor the useful suggestions that improved this reply.

R E F E R E N C E S

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D’Amico, S., Koper, K. D., Herrmann, R. B., Akinci, A. & Malagnini, L.,2010b. Imaging the rupture of the Mw 6.3 April 6, 2009 L’Aquila, Italyearthquake using back-projection of teleseismic P-waves, Geophys. Res.Lett., 37, L03301, doi:10.1029/2009GL042156.

D’Amico, S., Orecchio, B., Presti, D., Gervasi, A., Guerra, I., Neri, G.,Zhu, L. & Herrmann, R. B., 2011. Testing the stability of moment tensorsolutions for small and moderate earthquakes in the Calabrian-Peloritanarc region, Boll. Geo. Teor. Appl., 52, 283–298.

De Stefani, C., 1910. La livellazione sul litorale calabro-siculo dopo ilterremoto del 1908, Bollettino della Societa geologica Italiana, 29, 223–231.

Ferranti, L., Monaco, C., Antonioli, F., Maschio, L., Kershaw, S. & Verrubbi,V., 2007. The contribution of regional uplift and coseismic slip to thevertical crustal motion in the Messina Straits, Southern Italy: evidencefrom raised Late Holocene shorelines, J. geophys. Res., 112, B06401,doi:10.1029/2006JB004473.

Ferranti, L., Monaco, C., Antonioli, F., Maschio, L. & Morelli, D., 2008.Holocene activity of the Scilla fault, southern Calabria: insights frommorpho-structural and marine geophysical data, Tectonophysics, 453, 74–93.

Galli, P. & Bosi, V., 2002. Paleoseismology along the Cittanova fault: im-plications for seismotectonics and earthquake recurrence in Calabria(southern Italy), J. geophys. Res., 107, B2044, doi:10.1029/2001JB000234.

Ghisetti, F., 1984. Recent deformations and the seismogenic source in theMessina Straits (southern Italy), Tectonophysics, 109, 191–208.

Ghisetti, F., 1992. Fault parameters in the Messina Straits (southern Italy)and relations with the seismogenic source, Tectonophysics, 210, 117–133.

Jacques, E., Monaco, C., Tapponnier, P., Tortorici, L. & Winter, T., 2001.Faulting and earthquake triggering during the 1783 Calabria seismic se-quence, Geophys. J. Int., 147, 499–516.

Koper, K., Hutko, A., Lay, T. & Sufri, O., 2012. Imaging short-periodseismic radiation from the 27 February 2010 Chile (MW 8.8) earthquakeby back-projection of P, PP,and PKIKP waves, J. geophys. Res., 117,B02308, doi:10.1029/2011JB008576.

Loperfido, A., 1909. Livellazione geometrica di precisione eseguitadall’I.G.M. sulla costa orientale della Sicilia, da Messina a Catania,a Gesso ed a Faro Peloro e sulla costa occidentale della Calabriada Gioia Tauro a Melito di Porto Salvo, in Relazione della Com-missione Reale incaricata di designare le zone piu adatte per la ri-costruzione degli abitati colpiti dal terremoto del 28 dicembre 1908o da altri precedenti, pp. 131–156, Accademia Nazionale dei Lincei,Roma.

Monaco, C. & Tortorici, L., 2000. Active faulting in the Calabrian arc andeastern Sicily, J. Geodyn., 29, 407–424.

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