Groundwater – Geothermal preliminary model of the Acque Albule Basin (Rome): future perspectives of geothermal resources exploitation

This work presents the preliminary results of a groundwater and geothermal model applied to the hydrothermal system of the Tivoli- Guidonia plain, located in the east surroundings of Rome. This area, which is characterized by a thick outcropping travertine deposit, has been an important quarry extraction area since roman age. Today the extraction is in deepening helped by a large dewatering action. By an hydrogeological point of view, the travertine aquifer of the Tivoli- Guidonia Plain, is recharged by lateral discharge in the Lucretili and Cornicolani Mts., and by piping trough important regional faults, located in the basal aquiclude, in the central area of the basin. Piping hydrothermal groundwater is the main contribution on flow in the basin. Preliminary simulations of the groundwater-geothermal model, reproduce quite well the heat and mineralization plumes of groundwater observed in the travertine aquifer.

Organic components and diagenetic products in the travertine deposit at Villers-devant-Orval (S. Belgium)

The travertine deposit at Villers-devant-Orval (S. Belgium) formed during the Preboreal till the Boreal. In the first terrace studied in this paper, five lithostratigraphic units were distinguished, based on the presence of gravel, loam, peat and fine, medium grained and coarse travertine. Within the latter, encrusted branches and algal and cyanobacterial filaments are the most important organic components. Vadose diagenesis of the deposit is indicated by the presence of needle-crystals, fiber calcite crystals and dendrites. Meteoric phreatic diagenetic products occur as gothic-arch calcite crystals and euhedral crystals, which cement the pores.