sketch map of Stromboli island, from Hornig-Kjarsgaard et al. (1993).
Click on thumbnail to view large version and legend.
After the pioneering studies by
Cortese & Sabatini (1892) and Bergeat (1899), the geological evolution of
Stromboli has for a long time been ignored, probably because studies were
concentrated on the persistent eruptive activity. The first reasonable modern
geological study of the island was by Rosi (1980) who recognized four major
stratigraphic units: Paleostromboli, Vancori, Neostromboli and Recent Sciara.
The following is extracted from the much more detailed stratigraphy established
by Hornig-Kjarsgaard et al. (1993), with additions based on recent work
by Kokelaar & Romagnoli (1995) and Bertagnini & Landi (1996).
the oldest part of the Stromboli volcanic system, the "neck"
of Strombolicchio (a remnant of a volcanic conduit) rises from the
sea about 1.5 km NE of Stromboli (in the background). In this photograph,
taken on the early morning of 29 March 1990, a dense volcanic gas
plume is being carried down to the village of Stromboli, causing a
slight smell of sulfur even beyond Strombolicchio.
of phreatomagmatic deposits rich in accretionary lapilli. This outcrop,
photographed in September 1989, has meanwhile disappeared since it
lies in an area now in private property. Its location is between the
two main fractions of Stromboli village, San Vincenzo and San Bartolo.
The deposits may be correlated with violent explosive volcanism associated
with the sector collapse at Stromboli that left the Sciara depression
about 5000 years ago.
of a violent past: this outcrop at the W coast of Stromboli cuts through
scoria and lapilli fall deposits of the Scari formation (Hornig-Kjarsgaard
et al., 1993). The prominent light-colored horizon is a distal tephra
deposit erupted on the island of Ischia, between 40 and 60 ka ago.
In the stratigraphy of Hornig-Kjarsgaard
et al. (1993) and on the geological map of Stromboli by Keller et al.
(1993), the following volcanostratigraphic units are identified:
- 1) Strombolicchio eroded
- 2) Lower Paleostromboli
(PST) I lavas
- 3) PST I Pyroclastic
- 4) Upper PST I lavas
- 5) Lower Rina lavas
- 6) Omo lavas
- 7) Vallone Rina-Malo
- 8) Middle Vallone di
- 9) Upper Rina Lavas
- 10) Aghiastro lavas
- 11) Cavono pyroclastics
- 12) Diatreme vent of
- Vancori and Scari
- 13) Lower Scari Tuffs
- 14) Scari Lava
- 15) Upper Scari Tuffs
- 15a) Lower Vancori and
Middle Vancori Pyroclastics
- 16a, b) Lower Vancori
(Lower Vancori-a) and Frontone lavas (Lower Vancori-b)
- 17) Middle Vancori lavas
- 18) Upper Vancori breccias
- 19) Upper Vancori lavas
- 20) Frontone breccias
- 21) Roisa scoriae and
- 22) Neostromboli lavas
- 23) Timpone del Fuoco
- 24) Labronzo lavas
- 25) Nel-Cannestrà
- 26) Lazzaro pyroclastics
- Recent Stromboli
- San Bartolo lavas
- Pizzo sopra la Fossa
- Sub-recent Sciara lavas
- Recent Sciara activity
- Epiclastic volcanic
A fine, well-designed series
of pages showing the geological
evolution of Stromboli is available at Stromboli On-line.