FEBRUARY, 2021 – Italy is a seismically active country with a long history of earthquakes and volcanic eruptions. In the days of the Grand Tourists the volcano of Vesuvius was active. Visitors would often watch a nightly show of glowing lava and plumes of gas and ash, pouring from the crater. The science of archaeology began in Italy with excavations at Pompeii and Herculaneum starting in the 18th century. Probably the most famous volcanic eruption in Europe was the Vesuvius eruption of AD 79 when the Roman cities of Pompeii and Herculaneum were engulfed with lava, ash and volcanic debris.
Today the volcano of Etna, on the island of Sicily is active, and flows of lava are making their way slowly down the flanks of the mountain. Volcanoes and Earthquakes are all part of the endless geological processes that keep our planet dynamic and ever-changing. A volcanic eruption is a massive explosion of molten rock and gases that pour into our atmosphere and then fall under gravity back to Earth. It’s all part of a giant recycling process. When a volcano erupts vast amounts of molten material, ash and tiny volcanic stones are launched into the atmosphere. This debris will gradually fall back to Earth and over time consolidate into new rock surfaces and eventually create mineral rich, fertile soils, perfect for farming. It is a huge, never-ending process of construction, erosion and destruction that repeats itself infinitely. Plate boundaries, where the tectonic plates meet and volcanoes are the most obvious points on the Earth’s surface where we can see these processes in action.
- For a little more on the history of archaeology – why not read: Vesuvius and the eruption of 79 AD
- For a general introduction to earthquakes in Italy: Earthquakes in Italy
Whilst volcanoes can be intimidating they are also fascinating. Here’s a gallery of images from Southern Italy and Sicily – painted by early visitors and also more recent photos from when I have visited Vesuvius and Etna as a group leader over the least ten years.
The Vesuvius and Etna photos show very clearly the barren slopes surrounding these volcanoes. When a volcano is active there is a constant level of sulphuric gas emitted from the crater and surrounding fissures. From time to time there are lava flows and explosions associated with eruptions. This spewing of material from the crater down the mountainside creates huge fields of pumice (volcanic ash) and basalt (cooled lava) along with various mineral deposits. Over time these volcanic materials break down and eventually create fertile soil which is excellent for farming. On the lower slopes of Etna there are vineyards, fruit farms and even a honey-maker all benefitting from the mineral rich soils of a volcanic area.
The final photo in the gallery was taken by a member of the US Navy, from the naval base at Sigonella, just to the south-east of Mount Etna. This brilliant photo shows very clearly the plume of debris being pumped into the atmosphere and the apparent proximity of the aeroplanes on the ground. It is worth noting that the distance from Sigonella to Mount Etna is about 40 kms. It’s a really great photo – thanks to MSC 2nd Class Austin Ingram.
Lastly a special thank you for another really great photo by Mark Wilson from the Department of Geology, College of Wooster, Ohio. This photo shows Etna from the south and clearly reveals the numerous lava streams and fields of volcanic material erupted from the volcano over the decades. The crater and peak of Etna is top left in the photo. An old lava flow can be seen left centre, snaking down the hillside. An older crater, in the foreground (right) shows the vegetation succession beginning to get to grips with the bare rock of the southern slopes. Finally, the mountain hut or refuge (lower right) has been beautifully built out of the basalt rocks of the local area and consequently blends perfectly with the locality.
- For a fascinating diversion from every day life – why not visit our blog: The Educated Traveller
- Alternatively Covid permitting, consider a trip to Sicily with me in October 2021 – details here: The Treasures of Sicily it’ll be a very small, socially distanced group (probably 6-8 participants).
- Written: 18th February, 2021