Overblog
Editer l'article Suivre ce blog Administration + Créer mon blog

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

At the beginning of March, commemorative celebrations begin in Belpasso; they open on the occasion of the 350th anniversary of the eruption of Etna from 16 March to 11 July 1669 which destroyed the old town of Malpasso, the original site of the inhabitants of the current Belpasso.

Malpasso 1669 - Belpasso 2019 - Celebrations of the 350th anniversary of the eruption of Etna - Doc. etnalife / Twitter, featuring a reproduction of a fresco in Catania Cathedral illustrating this eruption - one click to enlarge

Malpasso 1669 - Belpasso 2019 - Celebrations of the 350th anniversary of the eruption of Etna - Doc. etnalife / Twitter, featuring a reproduction of a fresco in Catania Cathedral illustrating this eruption - one click to enlarge

This eruption is special and famous for more than one reason:

- flows were extremely high during this four-month event,

- the main vents are located on the flank of the volcano at an altitude of 800 to 850 m only,

- it generated the longest flow of Etna: 17 km.

- it has been the subject of a large number of detailed and detailed contemporary descriptions,

- it is the most recent eruption that has affected Catania,

- it is also one of the first documented cases of diversion testing of a lava flow.

Old engraving illustrating the eruption of Etna in 1669 - Doc. www.italysvolcanoes.com - The cradle of volcanology

Old engraving illustrating the eruption of Etna in 1669 - Doc. www.italysvolcanoes.com - The cradle of volcanology

On March 8, the earth trembles near Nicolosi. On March 11, a nine-kilometer radial crack opens ... six mouths will build on the crack!

In the following night, large quantities of lavas are emitted in the lower part. In about 20 hours, the flow drowns the city of Malpasso ... Fortunately, the 8000 inhabitants fled in time.

On March 12, seven more mouths open and then coalesce and form a crater that has a very high explosive activity. The wind will carry the ashes to the southern tip of Sicily. Little by little, the largest adventitious cones of Mount Etna are built : the Monti Rossi.

Map of the SSE flank of Etna with the 1669 flows in pink - in green, urbanized areas, including Catania (dark green barred); in brown, the sedimentary subsoil of Etna. - Map extracted from www.italysvolcanoes.com - The cradle of volcanology

Map of the SSE flank of Etna with the 1669 flows in pink - in green, urbanized areas, including Catania (dark green barred); in brown, the sedimentary subsoil of Etna. - Map extracted from www.italysvolcanoes.com - The cradle of volcanology

The lava continues to gush out of the complex and the flows, divided into three arms, destroy a dozen localities. The eastern branch of the lava flow crosses Misterbianco on March 25 before diving into a depression, the "Gurna di Nicito" occupied by a lake; violent explosion occurs on the same day at the summit crater, announcing the partial collapse of the cone.

The lava flow will fill the depression, then resume its advance towards Catania that reaches the 15 of April. It bypasses the city and arrives on 23 to the sea ... and advances there of 1500 meters.

Winchilsea, Heneage Finch 3d earl of (1689). A true and exact relation of the late prodigious earthquake & eruption of mount Aetna, or Mote-Gibello. London Printed by T. Newco

Winchilsea, Heneage Finch 3d earl of (1689). A true and exact relation of the late prodigious earthquake & eruption of mount Aetna, or Mote-Gibello. London Printed by T. Newco

On April 30, a breach opens in the wall of Catania, lava engulfs. The lava will submerge in the following days the western part of the city ... people try to oppose this invasion of lava, build derisory roadblocks, try to lock the river into dead ends. But another part of the ramparts gives way and the lava surrounds "Castel Ursino", located at that time on a cliff bordering the sea ("U" on the map). It will be relegated to one kilometer in the land, its moat filled with lava.

The eruption stopped in July 1669. In total, Etna emitted a volume of lava estimated between 0.5 and 1 km³, and about 0.25 km³ of pyroclasts. The lava field covers 37 km².

Lava "cicirara" containing centimeter plagioclase crystals (1600-1669) - photo Travelmarx blog

Lava "cicirara" containing centimeter plagioclase crystals (1600-1669) - photo Travelmarx blog

The eruption of 1669 probably drained a superficial magmatic reservoir, present for decades, as evidenced by the presence of abundant centimetric crystals of plagioclase (found in the lavas between 1600 and 1669). These lava are called "cicirara", translatable by "chick pitch", because of the appearance of the crystals. Etna will no longer produce "cicirara" after 1669. (Corsaro & al., 1996)

The eruption of 1669 - Doc.Meteoweb

The eruption of 1669 - Doc.Meteoweb

Sources:

- Etnalife - Etna eruzione1669, al via the celebrazioni nel 350 ° anniversario - link

- Italy's volcanoes - The cradle of volcanology - The 1669 eruption - link

- Etna vulcanologia: The erruzione del 1669 - by Dr. Salvatore Caffo 

- Guide to the volcanoes of Europe and the Canaries - by Mr. Krafft and Larouzière - ed. Delachaux & Niestlé

- On Etna - by Haroun Tazieff - ed. The Odyssey / Flammarion - eighth chapter.

Commenter cet article

Articles récents

Hébergé par Overblog