GNGTS 2024 - Atti del 42° Convegno Nazionale

Session 3.1 GNGTS 2024 Mapping the thermophysical propertes of Apennines rocks (Central Italy): implicatons for the temperature state of crust. Sabatni A. 1 , C. Pauselli 1 , S. Fuchs 2 , M. Ercoli 1 , P. Mancinelli 1 1 Università degli Studi di Perugia, Dip. Fisica e Geologia, Italy. 2 GFZ German Research Centre for Geosciences, Germany. This work presents the results obtained from the laboratory analysis of the thermophysical propertes of carbonate rocks and turbidites present in the northern Apennines. The aim was to determine and relate the thermophysical propertes of outcropping carbonate rocks belonging to the main geological formatons that characterize western Umbria (central Italy). The determinatons were carried out to observe the heat transfer capacity of these rocks, with varying temperatures and both in dry and saturated conditons; the porosites, that results less than 5%; the densites and the mineralogical compositon of 70 samples. The thermal conductvity values measured in dry conditons with three diferent devices based on the transient technique, difer by percentages of less than 10%. Mineralogical analysis indicates that the formatons under examinaton are mainly composed of calcite, with an abundance of quartz for some samples. The thermal conductvity values at ambient temperature of 20 – 25°C measured in dry conditons vary from 1.8 to 3.0 W/mK for samples with predominant calcite, and greater than 3.6 W/mK for samples with larger quanttes of quartz. The decrease in conductvity up to 200°C is about 30% for most samples. Theoretcal equatons based on the mineralogical compositon and porosity were analysed to fnd the right ft with the measured values, with the possibility of extending the results to other parts of the world. The results obtained from the study represent the basis for a more complete evaluaton of the temperature trend with depth, useful for the evaluaton of geothermal systems and for defning the rheological behaviour of the crust. Corresponding author: alessandro.sabatni1@student.unipg.it