From shallow to very shallow image of the highly active Kefalonia - Zakynthos fault system

4 pages, 2 figuresIn May 2022 and June 2023 two oceanographic cruises were carried out around the Ionian Islands with the aim of defining the real geometry of the strike-slip fault system of Kefalonia and of the reverse faults present south of Zakynthos. The acquired multidisciplinary and multiresolution data will also allow to understand the dynamics of the area offshore the Peoloponnese peninsula, the deformation of the surface sediments at the transition of the two systems, i.e. from reverse fault system to strike-slip fault system, and the relationship between the recorded seismicity and mapped fault activity. To date, the analysis of the processed data has allowed us to define the tectonic and morphological complexity of the fault system affecting the investigated area. [...]Thanks to the CNR for supporting the cruise with time ship, IONIANS 2022 project. Interpretation of seismic profile has been done using the Kindgom IHS Markit. Poseidon project has been supported by Eurofleet+ SEA02_13_POSEIDONPeer reviewe

Magnetic-dipole corrections to RK and RK* in the Standard Model and dark photon scenarios

In this work we evaluate the long-distance QED contributions, induced by the magnetic-dipole corrections to the final charged leptons, on the B meson decay widths B \u2192 (K, K*)\u2113+\u2113 12 and ratios RK,K* = \u393(B \u2192 (K, K*)\u3bc+\u3bc 12)/\u393(B \u2192 (K, K*)e+e 12), as well as on , 17RK,K 17\u3c4 (with \u3bc replaced by the \u3c4 lepton). QED long-distance contributions induced by the Coulomb potential corrections (Fermi-Sommerfeld factors) were also included. Corresponding corrections to the inclusive decay widths of B \u2192 Xs\u2113+\u2113 12, with \u2113 = e, \u3bc, \u3c4, are also analyzed for completeness. The magnetic-dipole corrections, which are manifestly Lepton Flavor Universality violating and gauge-invariant, are expected to be particularly enhanced in RK* for the dilepton mass region close to the threshold. However, we find that the largest contribution of all these corrections to the RK,K* observables do not exceed a few per mille effect, thus reinforcing the validity of previous estimates about the leading QED corrections to RK,K*. Finally, viable new physics contributions to RK,K* induced by the exchange of a massless dark-photon via magnetic-dipole interactions, which provide the leading contribution to the corresponding B \u2192 (K, K*)\u2113+\u2113 12 amplitudes in this scenario, are analyzed in light of the present RK,K* anomalies

Condition monitoring of railway overhead lines: correlation between geometrical parameters and performance parameters

This paper investigates the correlation between the results of a diagnostic system for overhead line, previously developed, tested and installed on both high-speed and commuter commercial trains, and the standard measures of overhead line geometry carried out by an inspection train. The diagnostic system proposed is rolling stock based, and adopts pantograph collector accelerations to calculate diagnostic indicators of the status of the overhead line. These indexes are computed in real time during the train run by suitable algorithms, and compared with threshold limits. The set-up proposed is inexpensive and easy to install on commercial service trains, aimed at marking an improvement on current time-scheduled methods for quality assessment of infrastructure

Back-Arc Spreading Centers and Superfast Subduction: The Case of the Northern Lau Basin (SW Pacific Ocean)

The Lau Basin is a back-arc region formed by the subduction of the Pacific plate below the Australian plate. We studied the regional morphology of the back-arc spreading centers of the Northern Lau basin, and we compared it to their relative spreading rates. We obtained a value of 60.2 mm/year along the Northwest Lau Spreading Centers based on magnetic data, improving on the spreading rate literature data. Furthermore, we carried out numerical models including visco-plastic rheologies and prescribed surface velocities, in an upper plate-fixed reference frame. Although our thermal model points to a high temperature only near the Tonga trench, the model of the second invariant of the strain rate shows active deformation in the mantle from the Tonga trench to ~800 km along the overriding plate. This explains the anomalous magmatic production along all the volcanic centers in the Northern Lau Back-Arc Basin

Oceanization starts from below during continental rupturing in the northern Red Sea

The role of magmatism in continental rupturing and in the birth of a new ocean is not well understood. Continental rupture can take place with intense and voluminous volcanism, as in the Southern Red Sea or in a relatively amagmatic mode, as in the Northern Red Sea. Mantle upwelling and melting may be affected by the south to north decreasing opening rate of the Red Sea and by the influence of the Afar plume, also decreasing from south to north. The tholeiitic basalts of the Red Sea spreading system contrast with the extensive Cenozoic basaltic lava fields of the western part of the Arabian peninsula that form one of the largest alkali basalt provinces in the world. In order to establish possible relationship between the Red Sea rift evolution and the western Saudi Arabia intraplate alkali volcanism, field work was carried out on Lunayyir, Ishara, al Kura and Khaybar volcanic fields. Collected samples cover a wide range of chemical diversity (from olivine basalt to trachyte) and span over a 20 Ma interval. We attempt a comparison of the geochemistry of igneous rocks from western Arabia dykes and volcanic fields with those from the Red Sea axis and from the islands of Zabargad and Brothers in the northern Red Sea, that represent basaltic melts injected into the thinned continental crust before continental rupturing and initiation of seafloor spreading. Gabbros drilled in the western Red Sea and exposed on the Brothers islands suggest that continental break up in the northern Red Sea, a relatively non-volcanic rift, is preceded by intrusion of oceanic-type basaltic melts that crystallize at progressively shallower crustal depths as rifting progresses towards continental break-up. A seismic reflection profile running across the central part of the southern Thetis basin shows a ~5 km wide reflector that marks the roof of a magma chamber located ~3.5 km below seafloor. The presence of a few kilometers deep subrift magma chamber soon after the initiation of oceanic spreading implies the crystallization of lower oceanic crust intrusives as a last step in a sequence of basaltic melt intrusion from pre-oceanic continental rifting to oceanic spreading. Thus oceanic crust accretion in the Red Sea rift starts at depth before continental break up, emplacement of oceanic basalt at the sea floor, and development of Vine-Matthews magnetic anomalies

Ultra-depleted melt refertilization of mantle peridotites in a large intra-transform domain (Doldrums Fracture Zone; 7–8°N, Mid Atlantic Ridge)

The Doldrums transform system offsets the Equatorial Mid Atlantic Ridge by ~630 km at 7–8° N. This transform system consists of four intra-transform spreading centers (ITRs) bounded by five transform faults. The northernmost ITR is linked to the MAR axis by a ~ 180 km-long transform. Here, during two R/V A. N. Strakhov expeditions (S06 and S09), mantle peridotites were dredged along the transverse and median ridge of the transform, across the western flank of the ITR valley. Residual harzburgites were mainly sampled along the northern Doldrums transform valley, whereas plagioclase-bearing peridotites showing evidence for melt-rock interaction characterize the ITR domain. Petrological and geochemical observations reinforced by geochemical modelling are used to define the behaviour of trace elements during melt extraction and melt-rock reaction in our rocks. Results suggest that residual peridotites derive from mantle rocks that have undergone a degree of partial melting up to 12%, with melting likely starting at the transition of garnet-spinel stability fields, whereas peridotites which suffered melt-rock reactions have been divided into two types: (i) pl-impregnated peridotites, formed by migration of melts at high porosity and high melt-rock ratio; and (ii) refertilized peridotites, generated at reduced porosity, when small fractions of the same percolating melt crystallized clinopyroxene and minor plagioclase. We suggest that the refertilizing agent was a melt highly depleted in incompatible trace elements, in turn produced by an ultra-depleted mantle source. This mantle experienced previous degrees of melt extraction at the ridge axis, before being transposed laterally along the transform where it melted a second time during the opening of the intra-transform spreading segment

Nonvolcanic tectonic islands in ancient and modern oceans

International audienc

Clinical use of cangrelor: a real world multicenter experience from South Italy Insights from the M.O.Ca. registry

Dual antiplatelet therapy (DAPT) with acetylsalicylic acid and oral P2Y12 inhibitor (P2Y12-I) represents the standard of care for patients with acute coronary syndromes (ACS) or with chronic coronary syndromes (CCS) treated with percutaneous coronary intervention (PCI). Cangrelor, the first intravenous P2Y12-I, is deemed to overcome the drawbacks of the oral administration; nevertheless real world data on this new drug are scanty. We sought to investigate routine clinical use of cangrelor in four interventional centers of Italy