We provide the first 3‐D resistivity image of the Pian Grande di Castelluccio basin, the main Quaternary depocenter in the hangingwall of the Mt.Vettore–Mt. Bove normal fault system (VBFS), ...responsible for the October 30, 2016 Mw 6.5 Norcia earthquake (central Italy). The subsurface structure of the basin is poorly known, and its relation with the VBFS remains debated. Using the recent Fullwaver technology, we carried out a high‐resolution 2‐D transect crossing the 2016 coseismic ruptures coupled with an extensive 3‐D survey with the aim of: (a) mapping the subsurface of the basin‐bounding splays of the VBFS and the downdip extent of intrabasin faults; (b) imaging the infill and pre‐Quaternary substratum down to ∼1 km depth. The 2‐D resistivity section highlights under the coseismic ruptures a main dip‐slip fault zone with conjugated splays. The 3‐D resistivity model suggests that the basin consists of two depocenters (∼300 and ∼600 m deep, respectively) filled with silty sands and gravels (resistivity <300 Ωm), bounded and cross‐cut by NNE‐, WNW‐, and NNW‐trending faults with throws of ∼200–400 m. We hypothesize that the NNE‐trending system acted during the early basin development, followed by NNW‐trending and currently active splays of the VBFS that overprint pre‐existing structures and locally control the infill architecture. Moreover, beneath the basin we detect a shallow NW‐dipping blind fault. The latter is likely a hangingwall splay of the adjacent regional Mts. Sibillini Thrust, which may have been partly involved in the rupture process of the Norcia mainshock.
Key Points
We show the first 3‐D shallow resistivity image of the Mw 6.5 Norcia earthquake fault system and its main Quaternary hangingwall basin
The mainshock fault system overprints NNE‐ and WNW‐trending faults that promoted the complex evolution of the Castelluccio hangingwall basin
We detect two main depocenters, 300 and 500–600 m deep, and a low‐angle fault to the south‐east of the basin, likely related to thrusting
Seismically induced ground effects characterize moderate to high magnitude seismic events, whereas they are not so common during seismic sequences of low to moderate magnitude. A low to moderate ...magnitude seismic sequence with a Mw = 5.16 ± 0.07 main event occurred from December 2013 to February 2014 in the Matese ridge area, in the southern Apennines mountain chain. In the epicentral area of the Mw = 5.16 main event, which happened on December 29th 2013 in the southeastern part of the Matese ridge, field surveys combined with information from local people and reports allowed the recognition of several earthquake-induced ground effects. Such ground effects include landslides, hydrological variations in local springs, gas flux, and a flame that was observed around the main shock epicentre. A coseismic rupture was identified in the SW fault scarp of a small-sized intermontane basin (Mt. Airola basin). To detect the nature of the coseismic rupture, detail scale geological and geomorphological investigations, combined with geoelectrical and soil gas prospections, were carried out. Such a multidisciplinary study, besides allowing reconstruction of the surface and subsurface architecture of the Mt. Airola basin, and suggesting the occurrence of an active fault at the SW boundary of such basin, points to the gravitational nature of the coseismic ground rupture. Based on typology and spatial distribution of the ground effects, an intensity I = VII−VIII is estimated for the Mw = 5.16 earthquake according to the ESI-07 scale, which affected an area of at least 90 km2.
Geochemical and geophysical surveys were carried out in the Cagno valley (Sila massif, central-northern Calabria, Italy) to investigate the gas bearing properties of a seismogenic fault (Lakes Fault, ...LF), discovered by paleoseismological analysis. Soil gas measurements (N2, O2, Rn, CO2, CH4 and light hydrocarbons) and exposure to γ radiations were performed along two detailed profiles (about 150m long), trending almost parallel to a trench crossing the LF. The highest values of Rn, γ radiation, CO2, CH4 and light hydrocarbons were detected in the area around the LF and 100m far away. In the central part of the profiles, where a hanging valley is present, geo-gas distribution is likely controlled by both lithology (colluvial deposits and peaty silt deposits, characterized by medium to low permeability) and the presence of a local cold aquifer. In particular, water table influences the circulation of the gas species in the sub-surface environment, as well as their distribution at the surface by playing a sort of sealing effect for the gas migration. In the area located about 100m westward of the fault, characterized by soils originated from altered granodiorites, the occurrence of a previously unknown blind fault is supposed. The multidisciplinary approach of this work allows to better understand the relationship between geochemical and geophysical analyses linked to migration processes of deep fluid through preferential leakage pathways providing some hints on the spatial influence of active tectonic.
► Application of soil gas and aquifers surveys in an natural gas storage site. ► Aquifers and soils are affected by shallow-derived degassing without any deep input. ► Gathered results represent the ...baseline for future storage purposes.
A geochemical survey, in shallow aquifers and soils, has been carried out to evaluate the feasibility of natural gas (CH4) storage in a deep saline aquifer at Rivara (MO), Northern Italy. This paper discusses the areal distribution of CO2 and CH4 fluxes and CO2, CH4, Rn, He, H2 concentrations both in soils and shallow aquifers above the proposed storage reservoir. The distribution of pathfinder elements such as 222Rn, He and H2 has been studied in order to identify potential faults and/or fractures related to preferential migration pathways and the possible interactions between the reservoir and surface. A geochemical and isotopic characterization of the ground waters circulating in the first 200m has allowed to investigation of (i) the origin of the circulating fluids, (ii) the gas–water–rock interaction processes, (iii) the amount of dissolved gases and/or their saturation status. In the first 200m, the presence of CH4-rich reducing waters are probably related to organic matter (peat) bearing strata which generate shallow-derived CH4, as elsewhere in the Po Plain. On the basis of isotopic analysis, no hints of thermogenic CH4 gas leakage from a deeper reservoir have been shown. The δ13C(CO2) both in ground waters and free gases suggests a prevalent shallow origin of CO2 (i.e. organic and/or soil-derived). The acquisition of pre-injection data is strategic for the natural gas storage development project and as a baseline for future monitoring during the gas injection/withdrawing period. Such a geochemical approach is considered as a methodological reference model for future CO2/CH4 storage projects.
The evaluation and management of prostate cancer (PCa) are based mainly on parameters such as the serum prostate-specific antigen level, clinical stage, and pathologic findings at biopsy or after ...surgery. The aim of this paper was to review the current roles of conventional imaging and multiparametric magnetic resonance imaging (mpMRI) techniques in the diagnosis of PCa. A non systematic literature search using the Medline and Cochrane Library databases was performed up to January 2012. Bibliographies of retrieved articles and review articles were also examined. Only those articles reporting complete data with clinical relevance for the present review (i.e., diagnosis, staging) were selected. The advent of a high performance (1.5T) and higher fields strength (3T), and thus, higher spatial resolution, increased the potentiality and the diffusion of MR examinations. Intense research has focused on the use of complementary techniques to improve the detection, characterization, and staging of PCa by MRI. This review article is divided into two major parts: the first one considers the technical aspects of mpMRI; the second part is intended to provide the impact of this technique on patients with PCa. Published data indicate an emerging role for MRI (particularly mpMRI combining T2 weighted imaging, diffusion weighted imaging, contrast enhanced MR, and spectroscopy) as the most sensitive and specific tool available for imaging PCa. MpMRI can provide metabolic information, characterize tissue and tumor vascularity, as well as tissue cellularity and correlate with tumor aggressiveness.
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