U and Th content in the Central Apennines continental crust: a contribution to the determination of the geo-neutrinos flux at LNGS

The regional contribution to the geo-neutrino signal at Gran Sasso National Laboratory (LNGS) was determined based on a detailed geological, geochemical and geophysical study of the region. U and Th abundances of more than 50 samples representative of the main lithotypes belonging to the Mesozoic and Cenozoic sedimentary cover were analyzed. Sedimentary rocks were grouped into four main "Reservoirs" based on similar paleogeographic conditions and mineralogy. Basement rocks do not outcrop in the area. Thus U and Th in the Upper and Lower Crust of Valsugana and Ivrea-Verbano areas were analyzed. Based on geological and geophysical properties, relative abundances of the various reservoirs were calculated and used to obtain the weighted U and Th abundances for each of the three geological layers (Sedimentary Cover, Upper and Lower Crust). Using the available seismic profile as well as the stratigraphic records from a number of exploration wells, a 3D modelling was developed over an area of 2^{\circ}x2^{\circ} down to the Moho depth, for a total volume of about 1.2x10^6 km^3. This model allowed us to determine the volume of the various geological layers and eventually integrate the Th and U contents of the whole crust beneath LNGS. On this base the local contribution to the geo-neutrino flux (S) was calculated and added to the contribution given by the rest of the world, yielding a Refined Reference Model prediction for the geo-neutrino signal in the Borexino detector at LNGS: S(U) = (28.7 \pm 3.9) TNU and S(Th) = (7.5 \pm 1.0) TNU. An excess over the total flux of about 4 TNU was previously obtained by Mantovani et al. (2004) who calculated, based on general worldwide assumptions, a signal of 40.5 TNU. The considerable thickness of the sedimentary rocks, almost predominantly represented by U- and Th- poor carbonatic rocks in the area near LNGS, is responsible for this difference.Comment: 45 pages, 5 figures, 12 tables; accepted for publication in GC

Molecular analysis of pediatric brain tumors identifies microRNAs in pilocytic astrocytomas that target the MAPK and NF-kappa B pathways

RT-qPCR confirms (a) up-regulation of miR-34a, miR-146a, miR-542-3p and miR-503 in pilocytic astrocytomas. (b) low expression of miR-124*, miR-129 and miR-129* in pilocytic astrocytomas. Relative expression shown as Log2 fold change compared to normal adult cerebellum and frontal lobe (normalized to miR-423-3p). Data represent two technical replicates ± SD. (ZIP 516 kb

Styles of tectonic inversion within syn-orogenic basins: examples from the Central Apennines, Italy

The geometry of several thrust-related folds in the Central Apennines of Italy results from a switch in deformation regime, from extension to contraction. This switch in tectonic regime occurred during the deposition of syn-orogenic sediments, and the emplacement and migration of the thrust belt±foredeep system towards the foreland in Neogene time. The styles of positive tectonic inversion result from normal faults that were steepened, rotated and truncated by thrusts, with local development of minor folds due to buttressing. Normal fault-controlled escarpments are also locally preserved in the forelimbs and backlimbs of thrust-related anticlines. The location and amplitudes of contractional structures across the belt re ̄ects the distribution of pre-thrusting normal faults within precursor syn-orogenic basins, a result that may improve our understanding of the evolution of Apennine, as well as other thrust belt±foredeep systems

The interaction of extensional and contractional deformations in orogenic belts: the example of the Central Apennines, Italy

The relationships among normal faults and thrusts in the Apennines of Italy are often unclear, and the local absence of syn-tectonic stratigraphic controls have led to contrasting interpretations on the relative chronology for both classes of structures. The activity of normal faults has been variously regarded as due to pre-, syn- or post-orogenic extension, and the contrasting evidence from different sites has produced an ongoing debate on the normal fault±thrust interaction. The results of a kinematic analysis on selected composite structures of the outer zones of the Central Apennines make it possible to unequivocally establish a relative chronology of extensional and contractional deformations. Detailed mapping, outcrop-scale observations and structural overprinting relationships support a positive inversion tectonic history, where normal faults and fault-controlled escarpments formed ®rst, and were later deformed by thrusts and related folds. All normal faults control the distribution of foredeep deposits, thus indicating that the recognised episode of positive inversion is related to the incipient stages of construction of the Apennine thrust belt. The systematic collection of structural data may help to unravel the evolution of adjacent sectors of the Apennine chain, as well as of other belt-foredeep±foreland systems whose extension±contraction relationships are poorly constrained

Caratterizzazione cinematica ed evoluzione deformativa delle faglie quaternarie con attività olocenica: esempi dall'Appennino centrale

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Kinematic characterization and deformational evolution of quaternary faults displaying a Holocenic activity: Some cases in the Central Apennines (Italy)

Geological and structural researches on Quaternary faults in key-areas of Umbria-Marche and Abruzzi in the Central Apennines, emphasised the occurrence of complex kinematic conditions, which are characterised by various and alternating generations of slip vectors along the same fault plane. Quantitative analyses of these structures allowed the reconstruction of a mean ellipsoid of finite extensional deformation characterised by a NE-SW stretching direction and a vertical shortening axis. The Quaternary tectonic framework is characterised by kine-matically interconnected active thrusting - in the Adriatic off-shore - and normal faulting - in the Apennines ridge -, which gave rise to a progressive deformation with mean shortening and extensional axes both trending NE-SW. Oblique ramps and transfer faults commonly developed along pre-existing N-S and E-W trending structures (such as Jurassic and Cretaceous faults). This complex kinematic situation is interpreted in terms of mechanical interactions caused by the variation of one or more tectonic stress modules, associated with the presence of oblique ramps and transfer faults

Pre-thrusting normal faults within syn-orogenic basins of the Outer Central Apennines, Italy: implications for Apennine tectonics

Extensional deformations are common within foredeep basins, and generally consist of hinterland-dipping normal faults located at the foredeep-foreland transition zones. Normal faults at the belt- foredeep boundaries, by contrast, are far less documented, nor their occurrence is predicted by simple orogenic load models. New sur- face data integrated with available seismic reflection profiles across the Central Apennines of Italy reveal the occurrence normal faults located in the inner edges of foredeep depressions. Extensional def- ormations are systematically found within sequentially younger Tor- tonian, Messinian and Early Pliocene foredeep basins, thus suggest- ing that normal fault development was an intrinsic feature of the evolving belt-foredeep-foreland system. Foreland extension is consis- tent with existing geodynamic models for the Apennines, and could represent the effects of lithospheric bending: its recognition and doc- umentation elsewhere could provide significant insights to improve our understanding of syn-orogenic basin dynamics