| Přispěvatelé: |
Alessandro Rebez, Paolo Giurco, DI MAIO, R., Piegari, E., Salone, R., DE PAOLA, C. |
| Popis: |
In the last twenty years a growing interest is noticed in studying the process of carbon dioxide degassing from the geosphere in various field of Earth Sciences, with the aim of defining relationship between gas flux on the ground and tectonic structures, quantifying deeply derived CO2 released into the atmosphere and studying volcanic and non-volcanic degassing processes (Frondini et al., 2018). While it is already recognized that volcanic degassing can introduce huge quantities of carbon dioxide into the atmosphere, only recent studies (Kerrick and Seward, 1996; Chiodini et al., 2000) have shown that non-volcanic degassing may be a globally significant input of CO2 into the atmosphere and that many areas where large emissions of non-volcanic carbon dioxide take place are also characterized by a some degree of permeability of the crust that often coincides with seismically active zones. Indeed, seismic data demonstrate the existence of a positive spatial correlation between gas discharges and extensional tectonic regimes and confirms that such processes would play a key role in creating pathways for the rising gases at micro- and macro-scales, increasing the rock permeability and connecting the deep crust to the earth surface. Therefore, the identification and the geometric characterization of the CO2-permeable active faults is fundamental, not only for the definition of the seismic-active zone geometry, but also for the understanding of the processes that govern the flow of fluids along the damage zone that convey the gases towards the surface. In this framework, numerical simulations of fluid flow in three-dimensional faulted models can help to identify the primary control parameters of fault-related fluid flow, their interactions, and to model the temporal evolution of the investigated system. In this work, we present the results of a numerical simulation of CO2 flow along an active fault in the Ciorlano area of Matese Ridge (Southern Apennines, Italy), which recent accurate geological and geochemical analyses classify as the area with the highest non-volcanic natural emissions of CO2 ever measured on Earth (Ascione et al., 2018). |
