SUGLI EFFETTI MECCANICI DI PROCESSI INDOTTI DA INCREMENTI LOCALIZZATI E TRANSIENTI DELLA PRESSIONE DEI FLUIDI E IMPLICAZIONI SULLE MODALITA' ED I TEMPI DI ACCREZIONE DEL SISTEMA A THRUST UMBRO-MARCHIGIANO

Abstract

The results of a geometrie analysis of the external zones of the Umbria - Marche thrust system allowed us to derive the aspect ratio of the system, whereas chronological data relative to the closing time of activity (CT A) of single thrusts fournished a linear relationship between CT A and the dis­tance X of a thrust from a reference point within the system. The computed values and the stability of the above parameters over a regional domain suggest that they can be related to processes that might play a major role in thrust tectonics. In particular they seem to support a model in which localized and transient increases of pore fluid pressure dominate rock behaviour during thrusting. [...]