Temperature dependence of the thermal parameters of some rocks

The dependence of thermal parameters (conductivity ? diffusivity k and specific heat cp) on temperature for eight rock samples coming from different deep geological formations of the Travale (Tuscany) geothermal area is investigated. The measurements of these thermal parameters were done by Mongelli et al. (1982). The results of the analysis by least square fitting techniques in the temperature range 20 °C ≤ T ≤ 240 °C have shown that: i) the dependence of A on T has the same hyperbolic mathematical form as that worked out by other authors for most crystalline rocks; ii) the dependence of k on T disclosed by our analysis gives the same hyperbolic canonical form of A on T; iii) a new temperature dependence of c can be derived by the functional relations ? (T) and k (T) through the well known expression cp = ?/?k