Volcanological and structural evolution of Roccamonfina volcano (Italy): origin of the summit caldera

Abstract

Roccamonfina volcano (Roman Magmatic Province) sits at the margin of the NE-trending Garigliano graben. The most important episodes in the volcano’s history (630–50 ka bp ) have been controlled by tectonic activity associated with the graben’s master-faults. Roccamonfina volcano comprises two main parts: a stratovolcano developed inside the graben, and a complex of centres developed on the south-eastern horst. The summit of the stratovolcano is truncated by a horse-shoe shaped caldera (dimensions 6.5 km by 5.5 km) with the longest axis trending NW. The caldera opens towards the SE along NE-trending faults, which belong to the same system as the graben faults. Stratigraphical evidence indicates that caldera collapse was not caused by explosive eruptive events emplacing ignimbrites, or by sector collapse preceding ignimbrite eruptions. Geomorphological and structural observations, together with geophysical evidence, suggest that collapse of the volcano summit occurred as a mechanical re-adjustment to the high rate of the Garigliano graben extension during a climax of the regional tectonism at around 400 ka bp . The present elliptical shape of the collapsed area is due to the superposition of a linear NE-trending graben structure in the east, and a sector collapse in the west.

Monitoring Epiphytic Lichen Biodiversity to Detect Environmental Quality and Air Pollution: the Case Study of Roccamonfina Park (Campania Region - Italy)

“…This complex is a kind of stratovolcano that was subjected to the collapse of the crater area, generating a caldera. Its volcanic apparatus is somehow similar to that of Vesuvius, particularly as for constitution, insulation and morphology (De Rita & Giordano, 1996). Moreover, the contiguous area of the regional park are, at present, experiencing a rapid process of industrial reconversion.…”

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“…42; Cole et al, 1992;De Rita & Giordano, 1996;Giannetti, 2001;Rouchon et al, 2008). It belongs to the Roman Magmatic Province (Washington, Fig.…”

“…The strato-cone is cut at the top by the poly-phased summit caldera, which shows a well defined semi-circular rim to the west, due to a major sector collapse event occurred at ca. 400 ka (De Rita & Giordano, 1996), and a more irregular rim to the East, due to the coalescence of other three main collapses (Cole et al, 1992;De Rita & Giordano, 1996;Giannetti, 2001). The upper slope of the strato-cone is made of leucite-bearing lavas older than 400 ka, which are covered downslope by the main ignimbrites, emplaced between 385 and ca.…”

“…The Roccamonfina Volcano is located at the intersection of a NE-SW extensional graben with regional NW-SE and N-S tectonic lineaments (Fig. 55), which cut the Mesozoic-Cenozoic Apennine carbonatic sequences (e.g., Giordano et al, 1995;De Rita & Giordano, 1996). The volcanic succession lies on marine to continental sedimentary deposits that fill the NE-SW Garigliano graben (Watts, 1987;Giordano et al, 1995).…”

“…The Roccamonfina Volcano is made up of lavas and pyroclastic rocks erupted in three main phases of activity (Fig. 56;De Rita & Giordano 1996;De Rita et al, 1998;Rouchon et al, 2008), which started at about 590 ka (Ballini et al, 1989a). The first phase (stratocone building phase -Roccamonfina synthem) was dominated by emplacement of leucite-bearing lavas interbedded with deposits of mild explosive eruptions both from the central volcano and from parasitic monogenetic centres (Figs 55, 56).…”