**5.3 Volcano-tectonic and structural implication into the silicic volcanism of Monte Amiata**

At Monte Amiata, the association of silicic volcanism with transtensive shear zones [45, 55] was significant in determining the volcanological character of the silicic volcanism. In this work, we were able to define the near-vent features, buried under younger units, and to infer the source area on the basis of thickness, physical features, and distribution of Monte Amiata SLLF eruptive units. The vent area of SLLFs was possibly identified with an eruptive fissure system located near the crest of the summit ridge and fed by linear dike swarms (**Figure 2**). A multi-vent source is recorded by changes in location of eruption source (**Figure 2**).

Monte Amiata magmas were vented by faults related to regional transtension along the Bagnore-Bagni San Filippo shear zone that has been active during the volcano activity [45, 55], leading to dominantly effusive eruptions.

Referring to this structural framework, the SLLFs of Monte Amiata are put in place following the ascent along a system of faults which in their upper portion define a summit axial rift zone, rather than real volcanic conduits. The geometry of these upwellings and the reduced quantity of gas present in the magma are probably the main factors that inhibit the formation of a fragmentation surface [45]. While the ability of this lava flows to maintain their viscosity, their anomalously high temperature for a long time determines the style of emplacement in long and thick lava flows.
