Geology of Stromboli
Geological Evolution of Stromboli (8)
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Red dots in the map link to thumbnail-pictures below. Each of these is again a link to a larger picture. In order to preserve delicate details in the photos, these have somewhat larger filesizes than is usual on STROMBOLI ON-LINE, typically in the order of 60-100KB. |
Strombolicchio (right) and island of Stromboli (centre) from the Northeast
The lavas of the Strombolicchio volcanic neck were
measured as 200'000 years old.
Therefore they are older than any part of Stromboli, which
emerged from the sea roughly 160'000 years ago.
Stromboli from the East
The boat is about to land at Scari (pier visible in the centre). Layered pyroclastic material left and slighly higher than the houses is from the «Scari units», roughly 35'000 y BP. Here even scoria and lapilli fall deposits were identified, which had erupted on the island of Ischia (!), between 40'000 and 60'000y BP.
Stromboli from the South: Punta Lena on the coast, Vancori summit above
The small flat terrace along Stromboli's southermost point, «la Lena», was inhabited by a few families in the past century. It is made of young depositional material. However, immediately behind, inside the deeper erosional gullies, some of the oldest rocks of the island can by found, dating back to the «Palaeo-Stromboli I» period.
Most of this side of the volcano is made up by somewhat younger lavas from the «Palaeostromboli II and III» period (about 62'000 to 35'000 y BP), and the «Vancori Period» (35'000 to about 13'000 y BP). Exactly below the highest point of the summit ridge, younger Vancori lava has spilled across some horizontally layered deposits, and descended towards la Lena.
Stromboli from the South-Southeast
Strong erosion, evident from the active scree slopes, has removed most of the younger «Vancori Period» lavas (except on the right) and has revealed «Palaeostromboli III» material. Note the colourful ash deposits exposed in the cliff on the right. Vertical cliffs and permanent danger from falling rocks has lead to the name «Malo Passo» for the section of coast on the left.
Although a path is shown on some topographic maps of Stromboli, it is virtually impossible (and extremely dangerous) to walk from Stromboli village to Ginostra.
Pizzo as seen from the path leading up to the Vancori
Lavas from the «Vancori» period appear light grey and - as a result of weathering - reddish in the right part of this image. We are looking towards the North-Northeast, along a fault line. On its left, the Vancori volcano has collapsed towards the Northwest. «Neo-Stromboli» and recent «Sciara volcano» lavas have built up a new cone, the highest point of which is Pizzo (916m, top left). Note the numerous erosional featers caused, not by natural forces, but the many tourists descending from Pizzo ;-) Strombolicchio is visible on the right.
View from Frontone towards Pizzo (left) and Vancori (right)
This panorama view shows the recent «Sciara volcano» (left half of panorama) residing inside the Vancori Caldera. Note the light coloured material exposed on the left side of Pizzo: This was erupted early in the «Sciara volcano» period and consists of strongly fumarolized, irregularly bedded near-vent pyroclastic material.
Stromboli from the East
All parts of Stromboli visible in this picture and covered by green vegetation belong to «Neo Stromboli». Note how this part of the volcano was extensively invaded by dikes, some of which are prominent dark vertical slabs of rock at or slightly above the coast. Another dyke appears as a reddish vertical slab in the exact centre of the photo. Such dikes may have structurally weakened the volcano and contributed to the final collapse of the Northwest sector of Neo Stromboli.
Dark grey, recent «Sciara volcano» lavas (on the left) have, to a large extent, re-filled the cavity left by the collapse. The darkest (i.e. freshest) lava flow is from 6.-12. February 1958.
The prominent peak on the upper right is Frontone, the Western end of the Vancori Caldera rim.
Sciara del Fuoco from the North
The northernmost section of Sciara del Fuoco was covered by the great lava flow of 1985/86.
Mostly «Neo Stromboli» lavas are on the left. Note the prominent layering dipping towards the North (left). The «regular» path from Stromboli village to Pizzo generally follows the horizon on the left.
On the right edge of the picture a small part of the Vancori is visible.
San Bartolo
Hotel Villaggio Stromboli (here seen in a photo from the early 1980ies) and all other houses along the coast of Piscità are built on the «San Bartolo» lavas from the end of the «Neo Stromboli» period. They were erupted by a lateral vent on the North side of the ridge leading up to Pizzo.