Mount Etna volcano (Italy) during the period 2001–2005 has undergone a period of intense eruptive activity marked by three large eruptions (2001, 2002–2003 and 2004–2005). These eruptions encompassed diverse eruptive styles and regimes: from intensely explosive, during 2001 and 2002–2003 eruptions, to exclusivelyeffusive in the 2004–2005 event. In this work, we put forward the idea that these three eruptions are the responseof the progressive arrival into the uppermost segment of the open-conduit system of a new magma, which was geochemically distinct in terms of trace element and Sr–Nd–Pbisotope signature from the products previously emitted by the Etnean volcano. The magma migrated upwards mainly through a peripheral tectonic system, which can be considered as eccentric in spite of its relative proximity to the main system. The ingress of the new magma and itsgradual displacement from the eccentric system into the uppermost sector of the open-conduit gave rise to different eruptive behaviours. At the beginning, the ascent of the undegassed magma, able to exsolve a gas phase at depth, and its interaction with closed-system magma reservoirsless than 10 km deep gave rise to the explosive events of 2001 and 2002–2003. Later, when the same magma entered into the open-conduit system, it took part in the steady-state degassing and partially lost its volatile load, leading to a totally effusive eruption during the 2004–2005 event. One further consideration highlighted here is that in 2001–2005, migration of the feeding axis from an eccentric and peripheral position towards the main open-conduit has led to the development of a new vent (South East Crater 2) located at the eastern base of the South East Crater through which most of the subsequent Etnean activity occurred.

Regimes of magma recharge and their control on the eruptive behaviour during the period 2001–2005 at Mt. Etna volcano

FERLITO, Carmelo;VICCARO, MARCO;
2012-01-01

Abstract

Mount Etna volcano (Italy) during the period 2001–2005 has undergone a period of intense eruptive activity marked by three large eruptions (2001, 2002–2003 and 2004–2005). These eruptions encompassed diverse eruptive styles and regimes: from intensely explosive, during 2001 and 2002–2003 eruptions, to exclusivelyeffusive in the 2004–2005 event. In this work, we put forward the idea that these three eruptions are the responseof the progressive arrival into the uppermost segment of the open-conduit system of a new magma, which was geochemically distinct in terms of trace element and Sr–Nd–Pbisotope signature from the products previously emitted by the Etnean volcano. The magma migrated upwards mainly through a peripheral tectonic system, which can be considered as eccentric in spite of its relative proximity to the main system. The ingress of the new magma and itsgradual displacement from the eccentric system into the uppermost sector of the open-conduit gave rise to different eruptive behaviours. At the beginning, the ascent of the undegassed magma, able to exsolve a gas phase at depth, and its interaction with closed-system magma reservoirsless than 10 km deep gave rise to the explosive events of 2001 and 2002–2003. Later, when the same magma entered into the open-conduit system, it took part in the steady-state degassing and partially lost its volatile load, leading to a totally effusive eruption during the 2004–2005 event. One further consideration highlighted here is that in 2001–2005, migration of the feeding axis from an eccentric and peripheral position towards the main open-conduit has led to the development of a new vent (South East Crater 2) located at the eastern base of the South East Crater through which most of the subsequent Etnean activity occurred.
2012
Magma supply; Ascent dynamics; Mixing; Volatiles; Degassing; Eruptive style
File in questo prodotto:
File Dimensione Formato  
Regimes of Magma Recharge in the period 2001-2005 at Etna.pdf

solo gestori archivio

Tipologia: Versione Editoriale (PDF)
Licenza: NON PUBBLICO - Accesso privato/ristretto
Dimensione 666.39 kB
Formato Adobe PDF
666.39 kB Adobe PDF   Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/20.500.11769/10192
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 32
  • ???jsp.display-item.citation.isi??? 31
social impact