Neutrinos from San Marco and Below

Order of magnitude estimates of radiogenic heat and antineutrino production are given, using the San Marco cathedral as an example. Prospects of determining the radiogenic contribution to terrestrial heat by detection of antineutrinos from natural radioactivity (geoneutrinos) are discussed. A three kton scintillator detector in three years can clearly discriminate among different models of terrestrial heat production. In addition, the study of geoneutrinos offers a possibility of improving the determination of neutrino mass and mixing, by exploiting the knowledge of Th/U abundance in the Earth.