Paleomagnetic Evidence of Non Rotational Tectonism in the Tuscan-Latium Geothermal Province (Italy)

Abstract

New paleomagnetic data, referring to the Late Miocene-Pliocene Autocthonous" sedimentaty in the extensional basins of Tuscan-Latium Tyrrhenian margin, demonstrate that no significant rotations affected this region since the Mcssinian-Early Pliocene time. These data suggest an evolution in the area hetween the and Rome that is different from that in the southern Apennines, where diffuse Plio- Pleistocene rotations were previously recognized. This geodynamic can better explain some different hehaviour between volcanic areas to the north and south of Rome: strong crustal influence in Neogene-Quaternary magmatic activity and volcanism to the north of Rome that attenuates southwards; presence to north of of a strong and large positive thermal anomaly that decreases sharply southwards, only partially to widespread outcrops permeable carbonatic platform units. Neogene-Quaternary anatectic events of Tuscany and north to the Latium regions could be influenced by the non-rotational gcodynamic feature. The inferred continuity between lower and upper parts of the lithosphere, since the Mcssinian to present, allowed the persistence of thermal processes various depths: these peculiar conditions produced a different tectonic hchaviour and greater heat flow density with respect to areas.