Search

Nowadays, groundwater is the most important resource on our planet. However, due to population growth, urbanisation, and climate change, this resource is often overexploited or contaminated. In this context, carbonate aquifers provide drinking water to approximately 25% of the global population. Due to aquifers heterogeneities and anisotropic fracture systems, they can be affected by potential contamination and their optimal exploitation represents a challenge aspect. In this particular scenario, carbonate mountain aquifers encompass valuable groundwater resources due to their high recharge rates and excellent water quality; therefore, the understanding of their hydrogeological characteristics are vital for aquifers protection and water management. A valid solution to explore water movement within such aquifers and to quantify the groundwater amount can be offered using artificial tracers. At the same time, the geomechanical surveys can deep the knowledge on fracture density and orientation, providing valuable insights about fracture connection and conductivity. This study combines the advantages of six artificial tracer tests performed in four deep wells (260-500 m b.g.l.) and a geomechanical survey used, among other, to estimate hydraulic conductivity of a mountainous carbonate aquifer located in Central Italy. The results obtained by different methods highlighted the presence of multiple layers with higher conductivity values, able to sustain the groundwater flow without significant piezometric level drawdown during water pumping operations. This approach provides an effective support to the water management company operating. [ABSTRACT FROM AUTHOR]

Carbonate aquifers are characterised by strong heterogeneities and their modelling is often a challenging aspect in hydrological studies. Understanding carbonate aquifers can be more complicated in the case of strong seismic events which have been widely demonstrated to influence groundwater flow over wide areas or on a local scale. The 2016–2017 seismic sequence of Central Italy is a paradigmatic example of how earthquakes play an important role in groundwater and surface water modifications. The Campiano catchment, which experienced significant discharge modifications immediately after the mainshocks of the 2016–2017 seismic sequence (Mmax = 6.5) has been analysed in this study. The study area is within an Italian national park (Sibillini Mts.) and thus has importance from a naturalistic and socio-economic standpoint. The research strategy coupled long-period artificial tracer tests (conducted both before and after the main earthquakes), geochemical and discharge analyses and isotope hydrology with hydrogeological cross-sections. This study highlights how the seismic sequence temporarily changed the behaviour of the normal faults which act predominantly as barriers to flow in the inter-seismic period, with water flow being normally favoured along the fault strikes. On the contrary, during earthquakes, groundwater flow can be significantly diverted perpendicularly to fault-strikes due to co-seismic fracturing and a consequent permeability increase. The interaction between groundwater and surface water is not only important from the point of view of scientific research but also has significant implications at an economic and social level. [ABSTRACT FROM AUTHOR]