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Late Quaternary faulting within the Southern Apennines seismic belt: new data from Mt. Marzano area (Southern Italy)
No full textcon allegata Carta Morfostrutturale fuori test
An integrated geophysical investigation of the upper crust in the epicentral area of the 1980 Ms=6.9 Irpinia earthquake (Southern Italy).
No full textEffects of metformin on plasma glucose, insulin, FFA, glucagon, growth hormone and cortisol responses to oral glucose in subjects with chemical diabetes
No full textFluid-Triggered Aftershocks in an Anisotropic Hydraulic Conductivity Geological Complex: The Case of the 2016 Amatrice Sequence, Italy
Full text linkThe mechanism by which faults interact each other is still a debated matter. One of the main issues is the role of pore-pressure diffusion in the delayed triggering of successive events. The 2016 Amatrice–Visso–Norcia seismic sequence (Central Apennines, Italy) provides a suitable dataset to test different physical mechanisms leading to delayed events. The sequence started on August 24, 2016, with the Amatrice mainshock (MW = 6), and was followed after more than 60 days by events in Visso (MW = 5.4) and Norcia (MW = 5.9). We analyzed the contribution of the static stress change and the role of fluids in the delayed triggering. Through 3D poroelastic modeling, we show that the Amatrice mainshock induced a pore-pressure diffusion and a normal stress reduction in the hypocentral area of the two aftershocks, favoring the rupture. Our parametric study employs a simple two-layered conductivity model with anisotropy in the seismogenic layer, characterized by larger conductivity values (K > 10−5 m/s) along the NNW-SSE direction. The one-way coupled pore-pressure 3-D diffusion modeling predicts the maximum increase of the pore pressure at the location of the two Visso earthquakes 60 days after the mainshock. The occurrence of anisotropic diffusivity is supported by the pattern of active faults and the strong crustal anisotropy documented by S-wave splitting analysis. We conclude that the temporal evolution of the sequence was controlled by the anisotropic diffusion of pore-pressure perturbations through pre-existing NNW-trending fracture systems
The effect of acetylsalicylic acid on insulin response to glucose and arginine in normal man
No full textLate Quaternary faulting within the Southern Apennines seismic belt: new data from Mt. Marzano area (Southern Italy)
No full textcon allegata Carta Morfostrutturale fuori test
Inferences on the upper crustal structure of the Southern Apennines(Italy) from seismic refraction investigations and subsurface data
No full textOrthogonal relation between wavefield polarization and fast S wave direction in the Val d'Agri region: An integrating method to investigate rock anisotropy
No full textWavefield polarization is investigated using 200 seismograms recorded by a network of 20 stations installed on rock outcrops in the Val d'Agri region that hosts the largest oil fields in the southern Apennines (Italy). Polarization is assessed both in the frequency and time domains through the individual-station horizontal-to-vertical spectral ratio and covariance-matrix analysis, respectively. We find that most of the stations show a persistent horizontal polarization of waveforms, with a NE-SW predominant trend. This direction is orthogonal to the general trend of Quaternary normal faults in the region and to the maximum horizontal stress related to the present extensional regime. According to previous studies in other areas, such a directional effect is interpreted as due to the presence of fault-related fracture fields, polarization being orthogonal to their predominant direction. A comparison with S wave anisotropy inferred from shear wave splitting indicates an orthogonal relation between horizontal polarization and fast S wave direction. This suggests that wavefield polarization and fast velocity direction are effects of the same cause: The existence of an anisotropic medium represented by fractured rocks where shear wave velocity is larger in the crack-parallel component and compliance is larger perpendicularly to the crack strike. The latter is responsible for the observed anisotropic pattern of amplitudes of horizontal ground motion in the study area
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