Volcano motionless landscape not at all inert

The volcanic system of Roccamonfina – whose magmatic source is located between the “Roman Comagmatic Province” and the “Campana Province” – occupies the northern slopewestern Campania for an area of about 450 Km2 for a base diameter of about 15 Km and runs along the southern border of Lazio.
The volcano of Roccamonfina (Monte S. Croce- 1005 meters) is now extinct, but during its millennial eruptive activity, has covered the surrounding landscape with pyroclastic deposits and lava flows, giving the entire area an incomparable atavistic suggestion.
This volcano is by size the fourth Italian volcano, while for altitude is the fifth after Etna, Vulture, Vesuvius and Mount Amiata and it is one of the most interesting volcanic systems in the world.
Its eruptive activity is dated between 630,000 and 50,000 years ago.
It is considered a volcano of considerable size, greater for example than those of Vesuvius, whose morphological structure recalls. Like Vesuvius, Roccamonfina can be classified as a polygenic volcano, with summit caldera derived from the collapse of the primordial volcano, within which a new volcano has been built, which in Roccamonfina is represented by the effusion of domes Lattani.
The geological history of the volcano of Roccamonfina has been divided into three main eruptive periods, separated by periods of quiescence and characterized by important variations of the eruptive modalities.
The first eruptive epoch is between 630,000 to 374,000 years ago. During this period about 100-120 km3 of lava and pyroclastic products were erupted.
Roccamonfina was a volcano layer built by alternating lava and pyroclastic deposits. The lavas, which in the early stages were very abundant, have tephritic-leucitic composition. From a petrographic point of view this period ranging from 549,000 to 374,000 years ago, and is characterized by the emission of high-potassium magmas. It has been suggested that the building of Roccamonfina reached a height of 1600-1800 meters.
The end of the first eruptive epoch is set by geologists around 400,000 years ago.

The appearance, that the territory could have at the end of the first eruptive stage, was that of a huge topographic depression not far from the Tyrrhenian coast; flanked by mountains and furrowed by the riverbeds of numerous streams, among which prevailed that of the Garigliano river, dominated, in a towering way, by the bulk of the original volcano layer and broken by a series of secondary craters.
In the terminal part of this first volcanic stage, the magma, highly viscous, reached the surface also through fractures oriented towards North East, which originated monumental dikes, still observable on the slopes of Conca della Campania and Galluccio.
In the second phase (350,000-150,000 years ago), the activity becomes predominantly explosive, with extensive pyroclastic flows and white pumice. It is mainly characterized by the emission of large volumes of medium and large volume pyroclastic castings. About 385,000 years ago, the so-called “Bruno Leucitic Tuff” was erupted. The term “Bruno Leucitic Tuff” indicates a succession of different types of ignimbrites.
The end of the second epoch of the activity of the volcano of Roccamonfina is placed by geologists at the end of the emission of the great ignimbrites.
After the eruptions of the ‘Tufo leucitico Bruno’ from about 327,000 years until 230,000 years ago, the volcano erupted again a series of ignimbrites, known together as “White Trachytic Tuffs”.
Eruptions occurred from a series of centers located within the caldera, along North East-South West direction faults.
The craters of these ignimbrite eruptions have been recognized at Cupa, Aulpi, S. Clemente and Galluccio.

The last phase of activity of Roccamonfina, which lasts at least 50,000 years ago, is characterized by modest explosive eruptions and the creation of two lava domes within the caldera area, along a system of fractures in the North East – South West direction, that of Santa Croce and Lattani.
In this third phase (150,000-53,000 years ago) deposits of Campanian ignimbrite also emerge in the volcano area, due to the volcanism of the phlegraean fields. It is a particular pyroclastic material that covers many of the surrounding hills and mountains, more commonly known as “Tufo grigio campano”.