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Earth of fire

Actualité volcanique, Articles de fond sur étude de volcan, tectonique, récits et photos de voyage

Publié le par Bernard Duyck
Publié dans : #Historical eruptions

Three fossilized tracks of footprints, discovered on the slopes of the Roccamonfina volcano in Campania at the end of the 18th century, have long been interpreted as the " Ciampate del Diavolo / the footprints of the Devil ". The demon came out of hell through the crater of the volcano to visit humans.

This belief lasted until the 21st century, when amateur archaeologists and then scientists became interested.

Traces of hominids in the " Devil's trails "on the Roccamonfina volcano - photo Mauro Fermariello / Science photo Library

Traces of hominids in the " Devil's trails "on the Roccamonfina volcano - photo Mauro Fermariello / Science photo Library

The human imprints have been well preserved, as they were printed in deposits of pyroclastic density current resulting from multiple collapses of a subplinian column emitted by an eruption of Roccamonfina, then covered by another pyroclastic flow. Erosion did not reveal them until the end of the 18th century.

The footprints, short and very wide (average length 24 cm and average width 10 cm), are kept on a steep slope, associated with handprints, and attributed to bipedal hominids having an autonomous process ... homo erectus or home Heidelbergensis, according to scientists of 1.5 m high.

These three tracks testify to the activities of the first known Europeans.

Roccamonfina volcano - satellite image

Roccamonfina volcano - satellite image

Distribution of ultrapotassic and related volcanic and sub-volcanic rocks in Italy and the surrounding area - (from Conticelli et al., 2007, 2010a, 2011 / Geological field trips - The Vesuvius and the other volcanoes of Central Italy - R. Avanzinelli & al .

Distribution of ultrapotassic and related volcanic and sub-volcanic rocks in Italy and the surrounding area - (from Conticelli et al., 2007, 2010a, 2011 / Geological field trips - The Vesuvius and the other volcanoes of Central Italy - R. Avanzinelli & al .

Simplified geological map of the Roccamonfin volcano. The insert shows the quaternary volcanoes of the Roman region (V: Vulsini, C: Cimini, Vi: Vico, S: Sabatini, AH: Alban Hills, E: Ernici, R: Roccamonfin, PF: Phlegrean Fields, SV: Somma Vesuvio (Modified by Giannetti and Francaviglia, 1994) - Doc. 'The Devil'sTrails' reference in sources

Simplified geological map of the Roccamonfin volcano. The insert shows the quaternary volcanoes of the Roman region (V: Vulsini, C: Cimini, Vi: Vico, S: Sabatini, AH: Alban Hills, E: Ernici, R: Roccamonfin, PF: Phlegrean Fields, SV: Somma Vesuvio (Modified by Giannetti and Francaviglia, 1994) - Doc. 'The Devil'sTrails' reference in sources

The Roccamonfina volcano belongs petrographically to the magmatic province of Campania, with the Phlegrean Fields, Vesuvius, the Pontine Islands, Ischia and Procida. This volcano represents its most northerly volcanic group.

Its basal diameter is 18-20 km., And its morphology in small caldera is marked by a sector of northern collapse.

 

Its first phase of activity between 1.54Ma and 340,000 years formed a stratocone, a collapse caldera, with between 385,000 and 335,000 years, successive deposits of important ignimbrites, called "Brown leucititic tuff ", marking the end of the first phase, with phonolitic domes.

A second phase of activity was marked by various units of pyroclastic flows: the "White trachytic tuff ", between 385,000- 335,000 years, and the "Yellow trachitic tuff ", between 327,000 and 230,000 years.

The terminal phase formed the trachybasaltic lava dome of Monte St. Croce, between 155,000 and 53,000 years ago.

Roccamonfina volcano - Foresta. View of the trampled surface with the last (distal) track segment (footprints 21-26) of track A. - Doc. 'The Devil'sTrails' reference in sources

Roccamonfina volcano - Foresta. View of the trampled surface with the last (distal) track segment (footprints 21-26) of track A. - Doc. 'The Devil'sTrails' reference in sources

The tracks are located in the non-welded pyroclastic deposits dated 385,000 - 335,000 years, rich in zeolite, and placed at a relatively low temperature (<600 ° C) and borrowed by descending hominids (traces of deep feet and hands ) on a relatively cool plastic surface, leaving their fingerprints on it.

 

Sources:

- The Devil's Trails: Middle Pleistocene Human Footprints Preserved in a Volcanoclastic Deposit of Southern Italy - Marco Avanzini & al. - Ichnos, 15: 3.179 - 189 - DOI: 10.1080 / 10420940802470458 - link

- Forestepping-backstepping stacking pattern of volcaniclastic successions: Roccamonfina volcano, Italy - D.De RitaaG.-Giordanoa-S.Millib - link

- The Vesuvius and the other volcanoes of Central Italy - R. Avanzinelli & al. - link

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