Increased rates of deformation and seismicity are well-established precursors to volcanic eruptio... more Increased rates of deformation and seismicity are well-established precursors to volcanic eruptions, and their interpretation forms the basis for eruption warnings worldwide. Rates of ground displacement and the number of earthquakes escalate before many eruptions1–3, as magma forces its way towards the surface. However, the pre-eruptive patterns of deformation and seismicity vary widely. Here we show how an eruption beginning on 19 March 2021 at Fagradalsfjall, Iceland, was preceded by a period of tectonic stress release ending with a decline in deformation and seismicity over several days preceding the eruption onset. High rates of deformation and seismicity occurred from 24 February to mid-March in relation to gradual emplacement of an approximately 9-km-long magma-filled dyke, between the surface and 8 km depth (volume approximately 34 × 106 m3), as well as the triggering of strike-slip earthquakes up to magnitude MW 5.64. As stored tectonic stress was systematically released, t...
Hugues Brenot (1), Nicolas Theys (1), Lieven Clarisse (2), Daniel Hurtmans (3), Pascal Hedelt (3)... more Hugues Brenot (1), Nicolas Theys (1), Lieven Clarisse (2), Daniel Hurtmans (3), Pascal Hedelt (3), Margarita Vasquez (3), Lucia Mona (4), Gelsomina Pappalardo (4), Simona Scollo (5), Mauro Coltelli (5), Tuomas Peltonen (6), Juhani Lahtinen (6), Marcus Hirtl (7), Delia Arnold (7), Timo Virtanen (8), Gerrit de Leeuw (8), Guðrún Nína Petersen (9), Sara Barsotti (9), Matthieu Plu (10), Gerhard Wotawa (7), and the EUNADICS-AV WP5 team
Basaltic fissure eruptions on Iceland are important for multiple reasons. They shed light on magm... more Basaltic fissure eruptions on Iceland are important for multiple reasons. They shed light on magmatic processes in general, and allow us to gain insight into the larger scale processes that form Earth’s crust. In relatively recent history gas emissions from Iceland’s basaltic fissure eruptions have produced a major impact to human activities both on Iceland and further afield. In this context, new insights into the nature of these eruptions, and mechanisms driving them are valuable.
The goal of this paper is to present CALPUFF, a new modeling system that can describe the movemen... more The goal of this paper is to present CALPUFF, a new modeling system that can describe the movements of a volcanic ash cloud, as well as the ash concentration in the air and on the ground, that is generated by a particular source. The CALPUFF system is comprised of three major parts: a geophysical preprocessor, a meteorological processor (called CALMET), and a Langrangian dispersal model (called CALPUFF).
<p>How well are our volcanoes monitored? Wh... more <p>How well are our volcanoes monitored? When and why should we review and enhance the monitoring setup for volcano surveillance? These questions are often raised at Volcano Observatories or at those Institutions in charge of monitoring volcanoes and their associated hazards. The Icelandic Meteorological Office (IMO) is responsible for monitoring natural hazards in Iceland, including volcanoes and volcanic eruptions. IMO operates an extended multidisciplinary monitoring network which comprises seismometers, cGPS, gas sensors, MultiGAS and DOASes, hydrological stations, strainmeters and tiltmeters, infrasound networks and webcams, with the aim of detecting in a timely manner potential unrest at any of the 32 active volcanoes in the country. Limited resources and funding opportunities often pose limitations on how extensive (in terms of number of sensors and their variety) a volcano monitoring network can be. Therefore, the Volcano Observatories are often required to decide how to prioritize the monitoring needs and find a balance in sensitivity, reliability, and efficacy of the network.  </p><p>In this contribution, we will present the results of the analysis performed at the IMO to rank the Icelandic active volcanoes by their threat and, consequently, to prioritize their monitoring needs. Some criteria (based on eruption frequency, potential hazards, infrastructure exposure and current status) are defined as guidelines and they are used to drive decisions regarding when and how to alter the monitoring setup. The specific case of Hekla volcano is used here to evaluate the validity of such criteria and to perform an analysis of the current capability of issuing a timely warning for one of the most dangerous volcanoes in Iceland. </p>
Increased rates of deformation and seismicity are well-established precursors to volcanic eruptio... more Increased rates of deformation and seismicity are well-established precursors to volcanic eruptions, and their interpretation forms the basis for eruption warnings worldwide. Rates of ground displacement and the number of earthquakes escalate before many eruptions1–3, as magma forces its way towards the surface. However, the pre-eruptive patterns of deformation and seismicity vary widely. Here we show how an eruption beginning on 19 March 2021 at Fagradalsfjall, Iceland, was preceded by a period of tectonic stress release ending with a decline in deformation and seismicity over several days preceding the eruption onset. High rates of deformation and seismicity occurred from 24 February to mid-March in relation to gradual emplacement of an approximately 9-km-long magma-filled dyke, between the surface and 8 km depth (volume approximately 34 × 106 m3), as well as the triggering of strike-slip earthquakes up to magnitude MW 5.64. As stored tectonic stress was systematically released, t...
Hugues Brenot (1), Nicolas Theys (1), Lieven Clarisse (2), Daniel Hurtmans (3), Pascal Hedelt (3)... more Hugues Brenot (1), Nicolas Theys (1), Lieven Clarisse (2), Daniel Hurtmans (3), Pascal Hedelt (3), Margarita Vasquez (3), Lucia Mona (4), Gelsomina Pappalardo (4), Simona Scollo (5), Mauro Coltelli (5), Tuomas Peltonen (6), Juhani Lahtinen (6), Marcus Hirtl (7), Delia Arnold (7), Timo Virtanen (8), Gerrit de Leeuw (8), Guðrún Nína Petersen (9), Sara Barsotti (9), Matthieu Plu (10), Gerhard Wotawa (7), and the EUNADICS-AV WP5 team
Basaltic fissure eruptions on Iceland are important for multiple reasons. They shed light on magm... more Basaltic fissure eruptions on Iceland are important for multiple reasons. They shed light on magmatic processes in general, and allow us to gain insight into the larger scale processes that form Earth’s crust. In relatively recent history gas emissions from Iceland’s basaltic fissure eruptions have produced a major impact to human activities both on Iceland and further afield. In this context, new insights into the nature of these eruptions, and mechanisms driving them are valuable.
The goal of this paper is to present CALPUFF, a new modeling system that can describe the movemen... more The goal of this paper is to present CALPUFF, a new modeling system that can describe the movements of a volcanic ash cloud, as well as the ash concentration in the air and on the ground, that is generated by a particular source. The CALPUFF system is comprised of three major parts: a geophysical preprocessor, a meteorological processor (called CALMET), and a Langrangian dispersal model (called CALPUFF).
<p>How well are our volcanoes monitored? Wh... more <p>How well are our volcanoes monitored? When and why should we review and enhance the monitoring setup for volcano surveillance? These questions are often raised at Volcano Observatories or at those Institutions in charge of monitoring volcanoes and their associated hazards. The Icelandic Meteorological Office (IMO) is responsible for monitoring natural hazards in Iceland, including volcanoes and volcanic eruptions. IMO operates an extended multidisciplinary monitoring network which comprises seismometers, cGPS, gas sensors, MultiGAS and DOASes, hydrological stations, strainmeters and tiltmeters, infrasound networks and webcams, with the aim of detecting in a timely manner potential unrest at any of the 32 active volcanoes in the country. Limited resources and funding opportunities often pose limitations on how extensive (in terms of number of sensors and their variety) a volcano monitoring network can be. Therefore, the Volcano Observatories are often required to decide how to prioritize the monitoring needs and find a balance in sensitivity, reliability, and efficacy of the network.  </p><p>In this contribution, we will present the results of the analysis performed at the IMO to rank the Icelandic active volcanoes by their threat and, consequently, to prioritize their monitoring needs. Some criteria (based on eruption frequency, potential hazards, infrastructure exposure and current status) are defined as guidelines and they are used to drive decisions regarding when and how to alter the monitoring setup. The specific case of Hekla volcano is used here to evaluate the validity of such criteria and to perform an analysis of the current capability of issuing a timely warning for one of the most dangerous volcanoes in Iceland. </p>
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Papers by Sara Barsotti