Weighted uncertainties used to detect seismogenic structures

Some new parameters related to the earthquake hypocentral locations are defined. They are based on probabilistic criteria, and their behaviour offers a quantitative representation of the space distribution of the seismicity. They are the hypocentral probability (HP), that is the probability that at least one focus has occurred in the sample volume, the hypocentral density (HD), a simplified assessment of HP, and the energy density (ED), where energetic contents are introduced into the HD. A more unbiased interpretation of the earthquake data set is therefore possible. An application to the Friuli region outlines in detail some evidence previously only partly suggested by standard elaborations.