Schiavon Beatrice, Petrone Chiara M, Forni Francesca, Pontesilli Alessio, Hu Haiyang, Scarlato Piergiorgio, Andronico Daniele, Bello Elisabetta Del, Nazzari Manuela, Mollo Silvio
Department of Earth Sciences, Sapienza - University of Rome, P. le Aldo Moro 5, 00185, Rome, Italy.
Volcano Petrology Group, Natural History Museum, Cromwell Road, London, SW7 5BD, UK.
Sci Rep. 2025 Jul 1;15(1):21393. doi: 10.1038/s41598-025-07005-6.
Investigating the dynamics and timescales of magmatic processes in open-conduit basaltic volcanoes is crucial for improving our understanding of explosive eruptions and better assessing volcanic hazards. Among these processes, the role of mush disaggregation and remobilisation within the plumbing system remains rather underexplored. This study examines the longevity and dynamics of the mush system beneath Stromboli volcano (Aeolian Islands, Southern Italy), whose persistent activity results from variable degrees of interaction between different magmatic components. The complex zoning patterns of plagioclase phenocrysts from 2003 to 2021 eruptions have been interrogated by combining in-situ Sr isotope compositions, thermometric modelling, and Mg diffusion chronometry. Our findings shed new light on the physicochemical changes within the plumbing system, the timescales of crystal residence in the shallow reservoir, and the timing of magma recharge events. Timescales of mafic recharges and mush remobilisations recorded by plagioclase suggest rapid magma-mush dynamics during violent explosions but more sluggish during normal activity. Sr isotope heterogeneities in plagioclase reveal that multiple mush generations at Stromboli have been active over millennia, with remobilisation events and crystal recycling driven by mafic magma recharges from depth. This is further supported by a complementary in-situ investigation of clinopyroxene phenocryst cores. A previously unseen, prehistoric, highly radiogenic mush has been actively remobilised in recent years, pointing out that older components of open-conduit basaltic systems may persist longer than previously hypothesised.
研究开放管道玄武质火山岩浆过程的动力学和时间尺度对于增进我们对爆发性火山喷发的理解以及更好地评估火山灾害至关重要。在这些过程中，管道系统内岩浆糊解体和再运移的作用仍未得到充分探索。本研究考察了斯特龙博利火山（意大利南部伊奥利亚群岛）下方岩浆糊系统的寿命和动力学，该火山持续活动是不同岩浆组分不同程度相互作用的结果。通过结合原位锶同位素组成、测温模拟和镁扩散年代测定法，对2003年至2021年火山喷发中斜长石斑晶的复杂分带模式进行了研究。我们的发现为管道系统内的物理化学变化、浅部储层中晶体的停留时间尺度以及岩浆补给事件的时间提供了新的线索。斜长石记录的镁铁质补给和岩浆糊再运移的时间尺度表明，在剧烈爆炸期间岩浆 - 岩浆糊动力学迅速，但在正常活动期间较为缓慢。斜长石中的锶同位素不均一性表明，斯特龙博利的多代岩浆糊在数千年间一直活跃，深部镁铁质岩浆补给驱动了再运移事件和晶体循环。对单斜辉石斑晶核的补充原位研究进一步支持了这一点。近年来，一种前所未见的、史前的、高放射性的岩浆糊被积极再运移，这表明开放管道玄武质系统的较老组分可能比之前假设的持续时间更长。
