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Convergent plate boundaries are often characterized by widely deformed zones, where coexisting tectonic processes and variable fault kinematics can occur. Here, we quantify this variability along the Africa‐Eurasia deformed boundary in southern Italy, based on the evaluation of geodetic strain rate by recent space geodesy observations and plate motions, which are integrated by main geometric properties of detected faults in the area. We propose a compilation of 160 known faults. We use numerical methods to predict fault kinematics and net slip rate, due to the geodetic deformation field with the inclusion of fault strain accommodation. The obtained tectonic setting is compared with the observable, showing a fault rake agreement of the 73%, which allows us to consider this approach potentially favorable to improve the knowledge of fault kinematics along diffuse plate boundaries, when fault properties are not directly available. Plain Language Summary: A boundary between two plates is not a single line but it is often a large area with diffuse deformation, simultaneous tectonic processes and complex geodynamics. Here, we analyze the Africa‐Eurasia convergent and deformed boundary in southern Italy, central Mediterranean, where the lineaments along which crustal blocks move, the faults, show variable motion directions. We integrated the data describing the accurate displacement of the Earth's surface coming from recent satellite observations and from global plate motion models, together with geometric characteristics of 160 known faults, which we compiled for the purpose of computing the deformation field, that is, the geodetic strain rate, and kinematics along the faults of the area, using numerical methods. The procedure to integrate geodetic and geological observed data allows us to model crustal deformation both offshore and onshore the study area, and the agreement of the 73% between observed versus predicted fault kinematics suggests that this approach can help to investigate tectonics deformation along diffuse plate boundaries worldwide, when fault properties cannot be directly observed. Key Points: We combine 392 recent Global navigation satellite system rates and the geometry of 160 faults of southern Italy to compute new strain rate field using numerical methodsWe present fault kinematics of the region and compare it to reference literatureWe obtain a tectonic setting which suggests this approach is useful to investigate fault kinematics along diffuse plate boundaries [ABSTRACT FROM AUTHOR]

A variety of tectonic processes spread along the circum‐Mediterranean orogenic belts driven by the convergence of major plates, episodes of slab retreat and lateral and vertical mantle flows. Here, we provide an updated view of crustal stress and strain‐rate fields for the Albanides belt in the eastern Adria‐Eurasia convergence boundary. We framed a new geodetic‐based source model for the 2019 Mw6.4 Durrёs earthquake in light of the regional deformation, propending for a transpressional west‐dipping seismogenic fault. Our results highlight a fault‐scale complexity which mirrors the long‐time scale deformation of the Albanides plate boundary, where the rotation induced by the fast Hellenic rollback is accommodated also by transpression on inherited structures. [ABSTRACT FROM AUTHOR]

The 24–27 December 2018 flank eruption at Mount Etna (Southern Italy) has been investigated through a multidisciplinary approach in which olivine chemical zoning and diffusion chronometry data were integrated with models inferred by GNSS (Global Navigation Satellite System) measurements. Inspection of the olivine chemical zoning from core to rim allowed the identification of some dominant ways of transfer and interaction between magmas pertaining to different magmatic environments. Most of crystal cores are representative of crystallization at pressure of 290–230 and 160–120 MPa. Olivine rims suggest re‐equilibration at shallow pressure (≤30 MPa). Geodetic‐based models indicate pressurization of near‐vertical prolate spheroidal sources centered at ∼7.2 km below sea level (bsl) between 9 June 2017 and 28 June 2018 and later at ∼5.1 km bsl between 28 June 2018 and the eruption onset. Geodetic data also highlight a change in the inflation rate since late June 2018 and later around November 2018, which has been here related to both replenishment phases and magma uprising across the plumbing system. Timescales of magma replenishment are in agreement with prolonged recharge from deep levels upward to shallow environments started about 6 months before the eruption, with further replenishment involving the upper magmatic environments just 3–16 days before the eruption. At present, the eruptive activity at the volcano is primarily controlled by pressure imbalances affecting extensive sections of the plumbing system, with possibility to develop persistent eruptive activity at the summit versus flank eruptions depending on fortuitous interruptions of the steady magma recharge/discharge rate at shallow levels. Key Points: The Christmas 2018 eruption of Mount Etna has been investigated through olivine chemical zoning, diffusion chronometry and geodetic dataData suggest prolonged recharge occurred since 6 months before the eruption and more importantly 3–16 days before Christmas 2018Pressure imbalances in the plumbing system now control the development of summit activity or flank eruptions at the volcano [ABSTRACT FROM AUTHOR]

Abstract: The eruptions of December 2015 and May 2016 at Voragine crater were among the most explosive recorded during the last two decades at Mt. Etna volcano. Here we present data coming from geophysics (infrasound, LP, VLP, volcanic tremor, VT earthquakes, and ground deformations) and petrology (textural and microanalytical data on plagioclase and olivine crystals) to investigate the preeruptive magma storage and transfer dynamics leading to these exceptional explosive eruptions. Integration of all the available data has led us to constrain chemically, physically, and kinetically the environments where magmas were stored before the eruption, and how they have interacted during the transfer en‐route to the surface. Although the evolution and behavior of volcanic phenomena at the surface was rather similar, some differences in storage and transfer dynamics were observed for 2015 and 2016 eruptions. Specifically, the 2015 eruptions have been fed by magmas stored at shallow levels that were pushed upward as a response of magma injections from deeper environments, whereas evidence of chemical interaction between shallow and deep magmatic environments becomes more prominent during the 2016 eruptions. Main findings evidence the activation of magmatic environments deeper than those generally observed for other recent Etnean eruptions, with involvement of deep basic magmas that were brought to shallow crustal levels in very short time scales (∼1 month). The fast transfer from the deepest levels of the plumbing system of basic, undegassed magmas might be viewed as the crucial triggering factor leading to development of exceptionally violent volcanic phenomena even with only basic magma involved. [ABSTRACT FROM AUTHOR]

Terra Nova, 24, 148-155, 2012 Abstract GPS measurements on Mount St. Helens spanning the 2004.00-2010.85 time interval, encompassing the 2004-2008 dome-building eruption, were analysed. First, a local reference frame was derived to isolate the volcanic ground deformation from the background tectonic pattern related to the interactions between the Pacific, Juan de Fuca and North American plates. Secondly, the resulting ground deformation patterns were modelled to constrain magmatic sources. Results suggest a vertically elongated magma chamber centred at 8-9 km depth beneath the summit area that deflated during the beginning of the dome growth and inflated since January 2008, indicating that the same primary magma reservoir was active both during and after the eruption in a magmatic system that is persistent over the time. [ABSTRACT FROM AUTHOR]

Terra Nova, 23, 339-348, 2011 Abstract Several volcanoes worldwide have shown changes in their stress state as a consequence of the deformation produced by the pressurization of a magmatic body. This study investigated seismic swarms occurring on the western flank of Mt. Etna in January 1997-January 1998. Integrating seismic observations and geodetic data, we constrained the seismogenic fault system, and on the basis of stress tensor inversion and SHMAX analyses, we inferred an inflating pressure source located at 5.5 km b.s.l. beneath the west portion of summit area. Evaluation of Coulomb failure stress related to the proposed model showed how a large part of the seismogenic fault underwent a significant Coulomb failure stress increase (500 kPa). We inferred the presence of a sub-vertical faulted region, potentially weak, N50°E-oriented beneath the western sector of Mt. Etna. This structure could be brought closer to failure, thereby generating seismic swarms as the effect of elastic stress transfer induced by movement and/or overpressure of magmatic masses within the upper crust under the volcano. [ABSTRACT FROM AUTHOR]

The tectonic deformation of the Lipari–Vulcano complex, one of the most important active volcanic areas of the Mediterranean region, is studied here through the analysis of 10 years (1996–2006) of GPS data from both three permanent and 13 non-permanent stations. This area can be considered crucial for the understanding of the interaction between the Eurasian and African plates in the Mediterranean area, and, in general, this work emphasizes a methodological approach, already applied in other areas worldwide ( J. Geophys. Res., 1996, 101, 27 957 ; J. Geodyn., 1999, 27, 213 ) where geodetic data and strain parameters maps of critical areas can help to improve our understanding of their geodynamical aspects. In this framework, this study is aimed at providing a kinematic deformation model on the basis of the dense geodetically estimated velocities of the Lipari–Vulcano complex. In particular, the observed deformation pattern can be described by a combination of (1) the main N–S regional compression and (2) a NNE–SSW compression with a small right-lateral strike slip component acting along a tectonic structure trending N°40W between the two islands. This pattern was inspected through a simplified synthetic model. [ABSTRACT FROM AUTHOR]

Volcanic eruptions are usually preceded by measurable signals of growing unrest, the most evident of which are the increase in seismicity and ground deformation. It is also important to identify precursors of a possible renewal of the volcanic activity and to distinguish between an eruptive activity characterized by an intrusion (with the related destructive power) and a migration of magma stored in the main conduits. The 2005–2006 eruption at Mt. Augustine (Alaska, USA) is a good example of a massive migration of magmatic fluids from depth (about 1 km b.s.l.) under the effect of gas overpressure. The movements, recorded by High Rate GPS (HRGPS) data (15 s of sampling and processing rate) from the stations deployed on the volcano, define the dimensions and the characteristics of the shallow plumbing system. In this study, we propose a model of the different stages preceding the effusive phase (the ‘precursory phase’), where gas overpressure in the body of the volcano opens the terminal conduit. [ABSTRACT FROM AUTHOR]