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The SE part of Turkey is characterized by a transtensional regime within the complex collision zone between the Anatolian, Arabian and African plates, which is bounded by two main faults, Dead Sea Fault and its splays on east and the Karasu Fault on west. In this tectonic and geodynamic context developed the Amik and further North, Erzin and Toprakkale districts, which are located onshore the Iskenderun Gulf, with the occurrence of a widespread and young alkaline volcanism dated from 1.57 to 0.05 Ma in Amik, and 2.25 to 0.61 Ma in Toprakkale. Here we present the results of a petrochemical and noble gases (He–Ar) study performed in basalts and basanites from the Basins in order to constrain the features of the mantle source. The major and trace elements composition indicate that the involved mafic melts could be the result of 0.8–2% partial melting of a predominantly spinel and garnet + spinel mantle, which has typical features of intra-plate OIB magmatism. The 4He/40Ar* ratios display two distinct ranges, roughly < 1 and > 1, for basalts and basanites respectively. The 3He/4He ratio of fluid inclusions in olivine crystals ranges from 7.29 to 8.03 Ra (being Ra the atmospheric 3He/4He ratio of 1.39 × 10− 6), which implies a rather homogenous helium isotope signature of the mantle source. Such values are commonly recorded in MORB-like reservoirs (namely 8 ± 1 Ra), confirming that lavas erupted in SE Turkey did not suffer any important process of crustal contamination. Combining the main evidences from the geochemical data of both rocks and noble gases of fluids inclusions, we suggest that the melt generation of the alkaline magmas was triggered by a stretching lithosphere resulting from asthenosphere upwelling and decompression melting, analogous to geodynamic models of the coeval Syrian alkaline volcanic rocks and the older NW Anatolian rocks, rather than by subduction or plume-related processes. Finally, the combined results of noble gas-rock geochemistry point

The SE part of Turkey is characterized by a transtensional regime within the complex collision zone between the Anatolian, Arabian and African plates, which is bounded by two main faults, Dead Sea Fault and its splays on east and the Karasu Fault on west. In this tectonic and geodynamic context developed the Amik and further North, Erzin and Toprakkale districts, which are located onshore the Iskenderun Gulf, with the occurrence of a widespread and young alkaline volcanism dated from 1.57 to 0.05 Ma in Amik, and 2.25 to 0.61 Ma in Toprakkale. Here we present the results of a petrochemical and noble gases (HeAr) study performed in basalts and basanites from the Basins in order to constrain the features of the mantle source. The major and trace elements composition indicate that the involved mafic melts could be the result of 0.8–2% partial melting of a predominantly spinel and garnet + spinel mantle, which has typical features of intra-plate OIB magmatism. The 4He/40Ar* ratios display two distinct ranges, roughly < 1 and > 1, for basalts and basanites respectively. The 3He/4He ratio of fluid inclusions in olivine crystals ranges from 7.29 to 8.03 Ra (being Ra the atmospheric 3He/4He ratio of 1.39 × 10− 6), which implies a rather homogenous helium isotope signature of the mantle source. Such values are commonly recorded in MORB-like reservoirs (namely 8 ± 1 Ra), confirming that lavas erupted in SE Turkey did not suffer any important process of crustal contamination. Combining the main evidences from the geochemical data of both rocks and noble gases of fluids inclusions, we suggest that the melt generation of the alkaline magmas was triggered by a stretching lithosphere resulting from asthenosphere upwelling and decompression melting, analogous to geodynamic models of the coeval Syrian alkaline volcanic rocks and the older NW Anatolian rocks, rather than by subduction or plume-related processes. Finally, the combined results of noble gas-rock geochemistry point to a w

The SE part of Turkey is characterized by a transtensional regime within the complex collision zone between the Anatolian, Arabian and African plates, which is bounded by two main faults, Dead Sea Fault and its splays on east and the Karasu Fault on west. In this tectonic and geodynamic context developed the Amik and further North, Erzin and Toprakkale districts, which are located onshore the Iskenderun Gulf, with the occurrence of a widespread and young alkaline volcanism dated from 1.57 to 0.05 Ma in Amik, and 2.25 to 0.61 Ma in Toprakkale. Here we present the results of a petrochemical and noble gases (HeAr) study performed in basalts and basanites from the Basins in order to constrain the features of the mantle source. The major and trace elements composition indicate that the involved mafic melts could be the result of 0.8–2% partial melting of a predominantly spinel and garnet + spinel mantle, which has typical features of intra-plate OIB magmatism. The 4He/40Ar* ratios display two distinct ranges, roughly < 1 and > 1, for basalts and basanites respectively. The 3He/4He ratio of fluid inclusions in olivine crystals ranges from 7.29 to 8.03 Ra (being Ra the atmospheric 3He/4He ratio of 1.39 × 10− 6), which implies a rather homogenous helium isotope signature of the mantle source. Such values are commonly recorded in MORB-like reservoirs (namely 8 ± 1 Ra), confirming that lavas erupted in SE Turkey did not suffer any important process of crustal contamination. Combining the main evidences from the geochemical data of both rocks and noble gases of fluids inclusions, we suggest that the melt generation of the alkaline magmas was triggered by a stretching lithosphere resulting from asthenosphere upwelling and decompression melting, analogous to geodynamic models of the coeval Syrian alkaline volcanic rocks and the older NW Anatolian rocks, rather than by subduction or plume-related processes. Finally, the combined results of noble gas-rock geochemistry point to a w

Optics for future X-ray telescopes will be characterized by very large aperture and focal length, and will be made of lightweight materials like glass or silicon in order to keep the total mass within acceptable limits. Optical modules based on thin slumped glass foils are being developed at various institutes, aiming at improving the angular resolution to a few arcsec HEW. Thin mirrors are prone to deform, so they require a careful integration to avoid deformations and even correct forming errors. On the other hand, this offers the opportunity to actively correct the residual deformation: a viable possibility to improve the mirror figure is the application of piezoelectric actuators onto the non-optical side of the mirrors, and several groups are already at work on this approach. The concept we are developing consists of actively integrating thin glass foils with piezoelectric patches, fed by voltages driven by the feedback provided by X-rays. The actuators are commercial components, while the tension signals are carried by a printed circuit obtained by photolithography, and the driving electronic is a multi-channel low power consumption voltage supply developed in-house. Finally, the shape detection and the consequent voltage signal to be provided to the piezoelectric array are determined in X-rays, in intra-focal setup at the XACT facility at INAF/OAPA. In this work, we describe the manufacturing steps to obtain a first active mirror prototype and the very first test performed in X-rays., Comment: Preprint version. The fully published paper is found at https://doi.org/10.1117/12.2189990

Optics for future X-ray telescopes will be characterized by very large aperture and focal length, and will be made of lightweight materials like glass or silicon in order to keep the total mass within acceptable limits. Optical modules based on thin slumped glass foils are being developed at various institutes, aiming at improving the angular resolution to a few arcsec HEW. Thin mirrors are prone to deform, so they require a careful integration to avoid deformations and even correct forming errors. On the other hand, this offers the opportunity to actively correct the residual deformation: a viable possibility to improve the mirror figure is the application of piezoelectric actuators onto the non-optical side of the mirrors, and several groups are already at work on this approach. The concept we are developing consists of actively integrating thin glass foils with piezoelectric patches, fed by voltages driven by the feedback provided by X-rays. The actuators are commercial components, while the tension signals are carried by a printed circuit obtained by photolithography, and the driving electronic is a multi-channel low power consumption voltage supply developed in-house. Finally, the shape detection and the consequent voltage signal to be provided to the piezoelectric array are determined in X-rays, in intra-focal setup at the XACT facility at INAF/OAPA. In this work, we describe the manufacturing steps to obtain a first active mirror prototype and the very first test performed in X-rays., Comment: Preprint version. The fully published paper is found at https://doi.org/10.1117/12.2189990

Una ridefinizione delle forme e dei confini della cittadinanza portano sempre più a concepire il consumo come nuova sfera dei diritti sociali e come nuovo spazio di azione pubblica