The 3 July 2019 paroxysm at Stromboli volcano (Italy): is Stromboli playing by new rules?

2019 年 7 月 3 日斯特龙博利火山爆发（意大利）：斯特龙博利火山是否遵循新规则？

• 批准号: NE/T009292/1
• 负责人: Chiara Maria Petrone
• 金额: $ 6.64万
• 依托单位: Natural History Museum
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2019
• 资助国家: 英国
• 起止时间: 2019 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FT009292%2F1
• 关键词: July; 2019; paroxysm; Stromboli; volcano

On the afternoon of 3 July 2019, a violent explosive event (called paroxysm) affected the entire crater terrace of Stromboli volcano in Southern Italy, generating two pyroclastic flows that advanced for about 1 km across the sea beyond the coastline. The eruptive column rose for about 4 km above the summit and was accompanied by intense fall of scoriae and pumice, mostly around the village of Ginostra in the southwestern sector of the volcano, setting the vegetation on fire and causing one fatality and one injured person. The death toll could have been much higher, considering that during the summer months there are hundreds of tourists climbing the volcano every evening. In fact, on the afternoon of 3 July 2019 there were 230 people waiting to start their climb. Stromboli is well-known as the lighthouse of the Mediterranean for its persistent "normal" Strombolian activity, consisting of low-energy explosions occurring every 10-20 minutes from multiple vents located in the crater area. This persistent activity is accompanied by lava flows at intervals of several years and, occasionally, is interrupted by discrete violent explosive events, such as the one that occurred on 3 July, which lasted several minutes, fed a km-long vertical column of gas, scoria and pumice that launched blocks up to 2-3 km from the source. In the last century there have been about 17 paroxysms with the strongest one, also associated with a tsunami, on 11 September 1930, and the most recent ones on 5 April 2003 and 15 March 2007. Paroxysms are sudden, infrequent and highly damaging events that are very difficult to forecast. Previous work at Stromboli has shown that each of the last 4 paroxysms over 70 years of recorded eruptive history were preceded by lava effusion. In particular, the two most recent paroxysms in 2003 and 2007 occurred after the effusion of a similar cumulative volume of lava over a period of a few weeks to months preceding the large explosive events. These considerations have led to the current hypothesis that the volume of the effusive activity can be used to forecast future paroxysmal events. However, the 3 July 2019 did not play by this rule; it was preceded by very limited effusive activity only two minutes before the explosive event. At the same time, and rather untypical for the most recent activity of Stromboli, effusive activity started immediately after the explosive event, accompanied by intense explosive activity, and is still ongoing at the time of writing (early August 2019), raising concerns about the possibility of a second paroxysm.It is clear that in order to enhance our ability to forecast such deadly events, it is crucial to understand their driving mechanisms. We propose to exploit this unique opportunity to capitalise on this unexpected event on 3 July 2019 through a detailed petrological and geochemical investigation of the eruptive products to unravel pre- and syn-eruptive magma ascent and degassing processes and their timescales, magma storage and crystallisation conditions as well as magma mixing processes and their timescales prior to eruption.This is a unique opportunity to obtain, for the first time, crucial and novel information on the processes and timescales of magma ascent and degassing of such a disruptive event using the solid eruptive products that directly probe the underlying magma plumbing system. As the clock on the short-lived radionuclide 210Po (half-life = 138 days), which is one of our probes for determining the timescales of magma ascent and gas transfer, is already ticking, funding this proposal is time-critical.

2019年7月3日下午，意大利南部斯特龙博利火山整个火山口阶地发生剧烈爆炸事件(称为爆发)，产生两股火山碎屑流，向海岸线外的海域推进约1公里。喷发柱在山顶上方约4公里处升起，并伴随着蝎子和浮石的猛烈坠落，主要分布在火山西南部的Ginostra村周围，导致植被着火，造成一人死亡，一人受伤。考虑到在夏季的几个月里，每天晚上都有数百名游客攀登火山，死亡人数可能要高得多。事实上，2019年7月3日下午，有230人等待开始攀登。斯特龙博利以其持续的“正常”斯特龙博利活动而闻名，该活动由位于火山口区域的多个喷口每10-20分钟发生一次低能量爆炸组成。这种持续的活动每隔几年就伴随着熔岩流动，偶尔还会被不连续的猛烈爆炸事件打断，例如7月3日发生的持续了几分钟的爆炸事件，注入了一公里长的垂直气柱、火山渣和浮石，将块体从源头发射到2-3公里。在上个世纪，大约发生了17次突发事件，其中最强烈的一次也与1930年9月11日的海啸有关，最近的一次发生在2003年4月5日和2007年3月15日。突发事件是突发性的、不常见的、极具破坏性的事件，非常难以预测。斯特龙博利先前的研究表明，在70年有记录的喷发史上，最后4次喷发中的每一次都是在熔岩涌出之前。特别是，最近的两次爆发发生在2003年和2007年，发生在大型爆炸事件之前的几周至几个月期间，熔岩的累积流出量类似。这些考虑导致了目前的假设，即热情洋溢的活动量可以用来预测未来的突发事件。然而，2019年7月3日并没有遵循这一规则；在爆炸事件发生前两分钟，非常有限的热情洋溢的活动才开始。与此同时，热情洋溢的活动在爆炸事件发生后立即开始，伴随着激烈的爆炸活动，在编写本报告时(2019年8月初)仍在进行，这对斯特龙博利最近的活动来说是相当不寻常的，这引发了人们对第二次爆发的可能性的担忧。显然，为了加强我们预测此类致命事件的能力，了解其驱动机制至关重要。我们建议利用这个独特的机会，利用2019年7月3日发生的这一意外事件，对喷发产物进行详细的岩石学和地球化学调查，以揭示喷发前和同时喷发的岩浆上升和脱气过程及其时间尺度、岩浆储存和结晶条件以及喷发前的岩浆混合过程及其时间尺度。这是一个独特的机会，首次利用直接探测潜在岩浆管道系统的固体喷发产品，获得关于岩浆上升和脱气的过程和时间的重要和新颖的信息。由于短寿命放射性核素210Po(半衰期=138天)的时钟已经在滴答作响，这是我们用来确定岩浆上升和气体转移时间尺度的探测器之一，因此为这一提议提供资金是至关重要的。

项目成果

Evolution of Stromboli basaltic plumbing system via magma recharges and mush rejuvenation.

斯特龙博利玄武岩管道系统通过岩浆补给和糊状再生的演变。

• DOI: 10.5194/egusphere-egu23-6218
• 发表时间: 2023
• 作者: Petrone C

Elemental diffusion chronostratigraphy: time-integrated insights into the dynamics of plumbing systems

元素扩散年代地层学：对管道系统动力学的时间积分洞察

• DOI: 10.1002/essoar.10504672.1
• 发表时间: 2020
• 作者: Petrone C

The 2019 Paroxyms at Stromboli Volcano (Italy): Timescales of Eruption Triggering

2019 年斯特龙博利火山（意大利）的火山爆发：触发喷发的时间尺度

• DOI: 10.46427/gold2020.2072
• 发表时间: 2020
• 作者: Petrone C

Where has the mush gone? A tale of a rejuvenated system

糊糊去哪儿了？

• DOI: 10.7185/gold2021.5883
• 发表时间: 2021
• 作者: Petrone C

Magma-mush dynamics control paroxysmal eruptions at basaltic volcanoes: the summer 2019 eruptions at Stromboli volcano (Italy).

岩浆糊状动力学控制玄武岩火山的阵发性喷发：2019 年夏季斯特龙博利火山（意大利）的喷发。

• DOI: 10.46427/gold2022.10562
• 发表时间: 2022
• 作者: Petrone C