{"title":"Dyke to sill deflection in the shallow heterogeneous crust during glacier retreat: part I","authors":"Kyriaki Drymoni, Alessandro Tibaldi, Fabio Luca Bonali, Federico Aligi Pasquarè Mariotto","doi":"10.1007/s00445-023-01684-7","DOIUrl":"https://doi.org/10.1007/s00445-023-01684-7","url":null,"abstract":"<p>Dykes and sills occupy Mode I (extension), Mode II (shear), or hybrid mode fractures and most of the time transport and store magma from deep reservoirs to the surface. Subject to their successful propagation, they feed volcanic eruptions. Yet, dykes and sills can also stall and become arrested as a result of the crust’s heterogeneous and anisotropic characteristics. Dykes can become deflected at mechanical discontinuities to form sills, and vice versa. Although several studies have examined dyke propagation in heterogeneous and anisotropic crustal segments before, the conditions under which dykes propagate in glacial-volcanotectonic regimes remain unclear. Here, we coupled field observations with 2D FEM numerical modelling to explore the mechanical conditions that encourage (or not) dyke-sill transitions in volcanotectonic or glacial settings. We used as a field example the Stardalur cone sheet-laccolith system, which lies on the Esja peninsula, close to the western rift zone, NW of the southern part of the Icelandic rift. The laccolith is composed of several vertical dykes that transition into sills and form a unique stacked sill ‘flower’ structure. Here, we investigate whether the Stardalur laccolith was formed under the influence of stresses caused by glacial retreat due to thickness variations (0–1 km) in addition to regional and local tectonic stresses (1–3 MPa extension or compression) and varied magma overpressure (1–30 MPa), as well as the influence of the mechanical properties of the lava/hyaloclastite contact. Our results show that the observed field structure in non-glacial regimes was formed as a result of either the mechanical (Young’s modulus) contrast of the lava/hyaloclastite contact or a compressional regime due to pre-existing dykes or faulting. In the glacial domain, the extensional stress field below the ice cap encouraged the formation of the laccolith as the glacier became thinner (subject to a lower vertical load). In all cases, the local stress field influenced dyke to sill deflection in both volcanotectonic regimes.</p>","PeriodicalId":55297,"journal":{"name":"Bulletin of Volcanology","volume":"372 1","pages":""},"PeriodicalIF":3.5,"publicationDate":"2023-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138508388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Michelle Parks, Freysteinn Sigmundsson, Vincent Drouin, Ásta R. Hjartardóttir, Halldór Geirsson, Andrew Hooper, Kristín S. Vogfjörd, Benedikt G. Ófeigsson, Sigrún Hreinsdóttir, Esther H. Jensen, Páll Einarsson, Sara Barsotti, Hildur M. Fridriksdóttir
{"title":"Correction to: Deformation, seismicity, and monitoring response preceding and during the 2022 Fagradalsfjall eruption, Iceland","authors":"Michelle Parks, Freysteinn Sigmundsson, Vincent Drouin, Ásta R. Hjartardóttir, Halldór Geirsson, Andrew Hooper, Kristín S. Vogfjörd, Benedikt G. Ófeigsson, Sigrún Hreinsdóttir, Esther H. Jensen, Páll Einarsson, Sara Barsotti, Hildur M. Fridriksdóttir","doi":"10.1007/s00445-023-01689-2","DOIUrl":"https://doi.org/10.1007/s00445-023-01689-2","url":null,"abstract":"","PeriodicalId":55297,"journal":{"name":"Bulletin of Volcanology","volume":"12 22","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135087073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Complex paths of magma propagation at Fernandina (Galápagos): The coexistence of circumferential and radial dike intrusion during the January 2020 eruption","authors":"Federico Galetto","doi":"10.1007/s00445-023-01688-3","DOIUrl":"https://doi.org/10.1007/s00445-023-01688-3","url":null,"abstract":"","PeriodicalId":55297,"journal":{"name":"Bulletin of Volcanology","volume":" 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135243393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kyriaki Drymoni, John Browning, Panagiotis Pomonis, Andreas Magganas
{"title":"Historical accounts provide insight on the geological evolution of the 20th century eruptions at Santorini volcano, Greece","authors":"Kyriaki Drymoni, John Browning, Panagiotis Pomonis, Andreas Magganas","doi":"10.1007/s00445-023-01681-w","DOIUrl":"https://doi.org/10.1007/s00445-023-01681-w","url":null,"abstract":"Abstract The 20th century eruptions of the Santorini volcano in Greece are the most recent activity of the volcano’s long lifespan. While the different eruptions taking place between 1925 and 1950 have traditionally been considered to exhibit similar eruptive styles, aspects of their evolution and precise information related to the individual eruption dynamics were poorly constrained. This study collates field reports and historical accounts, mainly from the Greek national scientific committee, which was assigned to study the volcanic activity in Nea Kameni Island with recent field campaigns. This analysis provides further insight into these eruptions and attempts to unravel the timing and style of explosive and effusive episodes that took place. Reconstruction of the recent geological evolution and of the eruptive history allow a more complete description of the eruption dynamics and associated unrest. These include fumarolic behaviour, explosion intensity, direction and volume of the lava flows, eruption duration, vent morphological changes (such as craters, domes, and horseshoe ramparts), textural characteristics and lava morphologies, as well as surface fracturing. Specific features related to first-hand accounts of the eruptions and associated products, in conjunction with our in situ post-eruptive geological study, allow an improved reconstruction of activity, both prior to and during the historical eruptions, which contributes to understanding the development of the eruption and enhances the forecast of potential future eruptions from patterns of precursory activity.","PeriodicalId":55297,"journal":{"name":"Bulletin of Volcanology","volume":"12 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135774245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jeremy Phillips, Shannon Williams, Anthony Lee, Susanna Jenkins
{"title":"Quantifying uncertainty in probabilistic volcanic ash hazard forecasts, with an application to weather pattern based wind field sampling","authors":"Jeremy Phillips, Shannon Williams, Anthony Lee, Susanna Jenkins","doi":"10.1007/s00445-023-01664-x","DOIUrl":"https://doi.org/10.1007/s00445-023-01664-x","url":null,"abstract":"Abstract Probabilistic forecasting of volcanic ash dispersion involves simulating an ensemble of realistic event scenarios to estimate the probability of a particular hazard threshold being exceeded. Although the number of samples that make up the ensemble, how they are chosen, and the desired threshold all set the uncertainty of (or confidence in) the estimated exceedance probability, current practice does not quantify and communicate the uncertainty in ensemble predictions. In this study, we use standard statistical methods to estimate the variance in probabilistic ensembles and use this measure of uncertainty to assess different sampling strategies for the wind field, using the example of volcanic ash transport from a representative explosive eruption in Iceland. For stochastic (random) sampling of the wind field, we show how the variance is reduced with increasing ensemble size and how the variance depends on the desired hazard threshold and the proximity of a target site to the volcanic source. We demonstrate how estimated variances can be used to compare different ensemble designs, by comparing stochastic forecasts with forecasts obtained from a stratified sampling approach using a set of 29 Northern European weather regimes, known as Grosswetterlagen (GWL). Sampling wind fields from within the GWL regimes reduces the number of samples needed to achieve the same variance as compared to conventional stochastic sampling. Our results show that uncertainty in volcanic ash dispersion forecasts can be straightforwardly calculated and communicated, and highlight the need for the volcanic ash forecasting community and operational end-users to jointly choose acceptable levels of variance for ash forecasts in the future.","PeriodicalId":55297,"journal":{"name":"Bulletin of Volcanology","volume":"2020 23","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135814027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nemi Walding, Rebecca Williams, Pete Rowley, Natasha Dowey
{"title":"Cohesional behaviours in pyroclastic material and the implications for deposit architecture","authors":"Nemi Walding, Rebecca Williams, Pete Rowley, Natasha Dowey","doi":"10.1007/s00445-023-01682-9","DOIUrl":"https://doi.org/10.1007/s00445-023-01682-9","url":null,"abstract":"Abstract Pyroclastic density currents (PDCs) are hazardous, multiphase currents of heterogeneous volcanic material and gas. Moisture (as liquid or gas) can enter a PDC through external (e.g., interaction with bodies of water) or internal (e.g., initial eruptive activity style) processes, and the presence of moisture can be recorded within distinct deposit layers. We use analogue experiments to explore the behaviour of pyroclastic material with increasing addition of moisture from 0.00–10.00% wt. Our results show that (1) the cohesivity of pyroclastic material changes with the addition of small amounts of moisture, (2) small increases in moisture content change the material properties from a free-flowing material to a non-flowable material, (3) changes in moisture can affect the formation of gas escape structures and fluidisation profiles in pyroclastic material, (4) gas flow through a deposit can lead to a moisture profile and resulting mechanical heterogeneity within the deposit and (5) where gas escape structure growth is hindered by cohesivity driven by moisture, pressure can increase and release in an explosive fashion. This work highlights how a suite of varied gas escape morphologies can form within pyroclastic deposits resulting from moisture content heterogeneity, explaining variation in gas escape structures as well as providing a potential mechanism for secondary explosions.","PeriodicalId":55297,"journal":{"name":"Bulletin of Volcanology","volume":"37 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136262337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Manon Pouget, Yves Moussallam, Estelle F. Rose-Koga, Haraldur Sigurdsson
{"title":"A reassessment of the sulfur, chlorine and fluorine atmospheric loading during the 1815 Tambora eruption","authors":"Manon Pouget, Yves Moussallam, Estelle F. Rose-Koga, Haraldur Sigurdsson","doi":"10.1007/s00445-023-01683-8","DOIUrl":"https://doi.org/10.1007/s00445-023-01683-8","url":null,"abstract":"","PeriodicalId":55297,"journal":{"name":"Bulletin of Volcanology","volume":"13 4","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134972579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Shallow storage, fragmentation depth, and eruption velocity of the 7.05 Ma Rattlesnake Tuff as indicated by breadcrust bubble ash morphology","authors":"Benjamin J. Andrews, Steve L. Quane","doi":"10.1007/s00445-023-01677-6","DOIUrl":"https://doi.org/10.1007/s00445-023-01677-6","url":null,"abstract":"","PeriodicalId":55297,"journal":{"name":"Bulletin of Volcanology","volume":"40 6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135218567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Simon Bufféral, Elisabetta Panza, Stefano Mannini, Ásta Rut Hjartardóttir, Adriano Nobile, Nils Gies, Birgir Vilhelm Óskarsson, Joël Ruch
{"title":"Surface fractures generated during the 2021 Reykjanes oblique rifting event (SW Iceland)","authors":"Simon Bufféral, Elisabetta Panza, Stefano Mannini, Ásta Rut Hjartardóttir, Adriano Nobile, Nils Gies, Birgir Vilhelm Óskarsson, Joël Ruch","doi":"10.1007/s00445-023-01666-9","DOIUrl":"https://doi.org/10.1007/s00445-023-01666-9","url":null,"abstract":"Abstract We use a comprehensive dataset of field observations, high spatial resolution drone orthomosaics and digital terrain models (DTMs) to map, quantify and characterize the extensive ground fracturing related to the 2021 seismo-tectonic and volcanic activity in the Reykjanes Peninsula (Iceland). The dataset, spans an area of about 30 km $$^2$$ <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"> <mml:msup> <mml:mrow /> <mml:mn>2</mml:mn> </mml:msup> </mml:math> , where we map nearly 20 000 ground cracks with metric to decametric lengths and centimetric extensional offsets, revealing a dominant dextral shear, in agreement with published seismic data. Although striking in a direction similar to the volcanic systems in the Reykjanes Peninsula (N030–040), most fractures appear as en-échelon structures globally aligned along N-S-striking fault zones up to 3–4 km long. By examining the timing of ground fracturing through repeated field observations, seismic data and InSAR images, we associate a fracture zone with most earthquakes of M $$_omega ge 5.0$$ <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"> <mml:mrow> <mml:msub> <mml:mrow /> <mml:mi>ω</mml:mi> </mml:msub> <mml:mo>≥</mml:mo> <mml:mn>5.0</mml:mn> </mml:mrow> </mml:math> that occurred in the month preceding the March 2021 Fagradalsfjall eruption. We describe three preexisting N-S fault zones, with fault segments that were reactivated up to three times during the pre-eruptive seismic activity, while the magma intrusion did not trigger graben-related ground fractures typically observed during magmatic injections. Our depiction of a system dominated by strike-slip tectonic features helps in understanding the geometry and bookshelf-mode of tectonic activity along a diffuse and highly oblique extensional plate boundary. Evidence of transient fracturing is typically quickly lost because of erosion or lava flow burial, highlighting a potential under-representation of diffuse fracturing when studying old tectonic and volcanic systems.","PeriodicalId":55297,"journal":{"name":"Bulletin of Volcanology","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135510830","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rachel Blandon, James E. Gardner, Fabian B. Wadsworth, Edward W. Llewellin, Jérémie Vasseur
{"title":"Experimental sintering of crystal-rich rhyolitic ash at high fluid pressures with implications for degassing of magma","authors":"Rachel Blandon, James E. Gardner, Fabian B. Wadsworth, Edward W. Llewellin, Jérémie Vasseur","doi":"10.1007/s00445-023-01678-5","DOIUrl":"https://doi.org/10.1007/s00445-023-01678-5","url":null,"abstract":"","PeriodicalId":55297,"journal":{"name":"Bulletin of Volcanology","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135853082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}