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We present the first rupture models of the two mainshocks of the 2012 northern Italy sequence, determined by jointly inverting seismic and geodetic data. We aim at providing new insights into the mainshocks for which contrasting seismotectonic interpretations are proposed in literature. Sources' geometric parameters were constrained by seismic reflection profiles, 3‐D relocations and focal mechanisms of mainshocks/aftershocks. Site‐specific velocity profiles were used to model accelerograms affected by strong propagation effects related to the Po basin. Our source models differ significantly from previous ones relying on either seismic or geodetic data. Their comparison against geological sections and aftershock distribution provides new insights about the ruptured thrust faults. The May 20th Mw6.1 mainshock activated the Middle Ferrara thrust‐ramp dipping ∼45° SSW‐wards, breaking a main eastern slip patch 4–15 km deep in Mesozoic carbonates (maximum slip 0.7–0.8 m) and Paleozoic‐Triassic basement rocks, and a small western patch in the basement. The May 29th Mw6.0 mainshock featured two separated asperities along the Mirandola thrust‐ramp dipping ∼42° S‐wards: an eastern asperity 4–15 km deep in Mesozoic carbonates and basement rocks (maximum slip 0.7 m) and a deeper western one (7–16 km depth) mainly in the basement (slip peak 0.8 m). On‐fault aftershocks were concentrated within the basement and Mesozoic carbonates, devoiding high‐slip zones. Slip and aftershock distribution was controlled by the rheological transition between Mesozoic carbonates and Cenozoic sediments. Unlike previous thin‐skinned tectonic interpretations, our results point to a complex rupture process along moderately dipping (40°–45°) thrust‐ramps deeply rooted into the Paleozoic crystalline basement. Plain Language Summary: The two M6 mainshocks of the 2012 Italy sequence are the strongest earthquakes ever observed in the Po Plain, a strategic region for the Italian economy. The mainshocks ruptured blind thrust‐faults, however their source models and seismotectonic interpretation are still debated because the thrust‐system architecture is controversial. Contrasting thick‐skinned and thin‐skinned tectonic models are proposed. In thick‐skinned interpretations, shortening is accommodated by thrust‐ramps rooted into the crystalline basement that represent main seismogenic structures, whereas in thin‐skinned interpretations, shortening and seismicity are controlled by listric faults splaying out from dècollement levels in the sedimentary crust. A comprehensive analysis of the mainshocks' source represents an opportunity to provide new insights into the seismogenesis in northern Italy and on a broader scale into seismotectonics of thrust‐and‐fold belts. We get a complete picture of the mainshocks kinematics by jointly inverting, for the first time, seismic and geodetic data, and unravel rupture heterogeneities not resolved by previous studies. By integrating source models with aftershock locations and geological models, we propose a comprehensive seismotectonic interpretation of the sequence. We conclusively identify the ruptured faults that correspond to thrust‐ramps rooted into the crystalline basement and evidence the key role played by lithological changes in the rupture process. Key Points: Rupture models of the 2012 northern Italy mainshocks obtained by inverting the most comprehensive geodetic and strong motion data set to dateBoth mainshocks ruptured two asperities along moderately dipping thrusts rooted into the Paleozoic crystalline basement down to ∼15 km depthAsperities located in Mesozoic carbonates and Paleozoic basement and slip distribution controlled by lithological and structural barriers [ABSTRACT FROM AUTHOR]

The SW Iberian margin is one of the most seismogenic and tsunamigenic areas in W‐Europe, where large historical and instrumental destructive events occurred. To evaluate the sensitivity of the tsunami impact on the coast of SW Iberia and NW Morocco to the fault geometry and slip distribution for local earthquakes, we carried out a set of tsunami simulations considering some of the main known active crustal faults in the region: the Gorringe Bank (GBF), Marquês de Pombal (MPF), Horseshoe (HF), North Coral Patch (NCPF) and South Coral Patch (SCPF) thrust faults, and the Lineament South strike‐slip fault. We started by considering for all of them relatively simple planar faults featuring with uniform slip distribution; we then used a more complex 3D fault geometry for the faults constrained with a large 2D multichannel seismic dataset (MPF, HF, NCPF, and SCPF); and finally, we used various heterogeneous slip distributions for the HF. Our results show that using more complex 3D fault geometries and slip distributions, the peak wave height at the coastline can double compared to simpler tsunami source scenarios from planar fault geometries. Existing tsunami hazard models in the region use homogeneous slip distributions on planar faults as initial conditions for tsunami simulations and therefore underestimate tsunami hazard. Complex 3D fault geometries and non‐uniform slip distribution should be considered in future tsunami hazard updates. The tsunami simulations also support the finding that submarine canyons attenuate the wave height reaching the coastline, while submarine ridges and shallow shelves have the opposite effect. Plain Language Summary: Deformation along the present‐day plate boundary between Africa and Eurasia off SW Iberia is distributed over a 200‐km‐wide and 600‐km‐long area, and is mainly accommodated by thrusts and strike‐slip faults. The region hosts frequent seismic activity of moderate magnitude punctuated by higher magnitude events, which have also originated major historical and pre‐historical tsunamis. The run‐up and coastal area affected by these tsunamis depend on the characteristics and location of the seismic source, bathymetry, and morphology of the coasts. Previous tsunami hazard assessments in the region used simplified fault models for tsunami simulations, ignoring the detailed 3D fault geometry and slip distribution. To investigate the sensitivity of the tsunami impact and eventually of the hazard to these complexities, we have carried out a series of tsunami simulations using planar and 3D fault surfaces, as well as homogeneous and heterogeneous slips. To build the fault surfaces, we used a large dataset of 2D multichannel seismic profiles that images the active faults in the region. Our study indicates that using the more complex fault models produce significantly larger tsunamis with the modeled wave heights at the coastline that can be several times bigger than those generated using planar fault sources. Key Points: The tsunami is sensitive to both the fault geometry and the slip distributionIntroducing complexity into the fault geometry and slip distribution can strongly enhance the simulated wave height at the coastOversimplified source models may hinder the prediction of the tsunami intensity, hence the tsunami hazard analysis [ABSTRACT FROM AUTHOR]

The tsunami source of the 2021 MW 8.1 Raoul Island earthquake in the Kermadec subduction zone was estimated by inverting the tsunami signals recorded by Deep‐ocean Assessment and Reporting of Tsunamis (DART) bottom pressure sensors and coastal tide‐gauges. The main asperity of up to 5 m of slip is located northeastward from the hypocenter, with features compatible with the aftershock distribution and rapid back‐projection analysis. Three earthquakes of MW ∼8 or larger which also produced moderate tsunamis happened in the 20th century in the same portion of the subduction zone. This is the first great tsunamigenic event captured by the new New Zealand DART network in the South West Pacific, which proved valuable to estimate a robust image of the tsunami source. We also show a first proof of concept of the capability of this network to reduce the uncertainty associated with tsunami forecasting and to increase the lead time available for evacuation for future alerts. Plain Language Summary: We estimated the tsunami source for the 4 March 2021 Raoul Island earthquake (MW 8.1), obtained by inverting tsunami data from tide‐gauges and open ocean Deep‐ocean Assessment and Reporting of Tsunamis (DART) stations. The main asperity of up to 5 m of slip is located northeastward from the hypocenter, with features compatible with the aftershock distribution and rapid back‐projection analysis. This event is important because it was the strongest one of three earthquakes that occurred within hours during the same day. Moreover, it caused the largest of three tsunami that altogether represent a great test for the New Zealand DART new network. The results demonstrate the potential importance of this new DART network for resolving the tsunami source and for early warning purposes as it can reduce the uncertainty of the tsunami forecasts and at the same time increase the lead time available for evacuation. Key Points: Tsunami source of the 2021 MW 8.1 Raoul Island earthquake by inverting tsunami waveformsThe main slip peaks at 5 m and is located at a depth of ∼20–30 and ∼100 km north of the epicenterNew Deep‐ocean Assessment and Reporting of Tsunamis network was crucial for characterizing the source and will significantly reduce the uncertainty and speed up future warnings [ABSTRACT FROM AUTHOR]

Increasingly, economies that have traditionally benefited from offshoring are losing some of their strategical advantages, with a consequent increase in backshoring by developed economies. This paper describes the phenomenon and tries to shed light on the current challenges, trends, and debates in the area, and on the main determinants of backshoring. A new phenomenon known as nearshoring is also analysed—this consists of relocating some previously offshored manufacturing activities so that they are now close to previous core locations, but not so close as to suffer from disagglomeration effects. This combines the advantages of offshoring and backshoring. [ABSTRACT FROM AUTHOR]

We investigate the rupture process of the 2016, Mw6.1 Amatrice earthquake, the first shock of a seismic sequence characterized by three damaging earthquakes occurred in central Italy between August and October. We jointly invert strong motion, High‐Rate GPS data, GPS, and DInSAR displacements and we adopt ad hoc velocity profiles of the crust below each station. The retrieved source model reveals a high degree of complexity, characterized by a prominent bilateral rupture with low slip at the hypocenter, two well‐separated slip patches and a rupture front accelerating when breaking the largest patch. The rupture of the main asperity features a slip‐velocity pulse that is impeded ahead of its current direction and splits into two pulses. In this fault section we find clues of structural and rheological control of the rupture propagation due to the fault system segmentation. Plain Language Summary: This work provides relevant information for Seismology community and the results may have important implications for earthquake hazard assessment. Indeed, indication of the role played by the fault segmentation in limiting the size of single earthquake in Central Italy is gained.In particular, we retrieve the source process of the 2016 Amatrice, central Italy, earthquake by jointly invert for a comprehensive dataset (strong motion, HRcGPS, GPS and DInSAR measurements).The main outcome of our study is that the rupture process has been characterized by a strong geometrical and rheological control due to the presence of important segmentation of the thrust fault system, distinctive of the central Apennines. Indeed, our results provide a complete description of the rupture propagation and inhibition due to the presence of inherited tectonic structures, which role in the seismic sequence evolution could be due to the favourable or unfavourable orientation within the active stress regime geometries and rheological variations between fault blocks. We believe that, in this context, our results are of potential impact for a broad readership because the interaction between new and/or inherited faults, strongly influences the fault segmentation and fault lengths, determining the maximum magnitude of individual earthquakes and consequently the seismic hazard. Key Points: Full kinematic rupture process of the 2016 Amatrice earthquake was retrieved from nonlinear joint inversion of Strong Motion, HRcGPS, GPS, and DInSAR dataThe complexity of the rupture history has been investigated by means of a rupture velocity and rupture mode propagation detailed analysisThe rupture process of the 2016 Amatrice earthquake has been characterized by a strong geometrical and rheological control due to the fault system segmentation in the central Apennines [ABSTRACT FROM AUTHOR]