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Simulating lava flows on a gentle slope is complex since they can propagate in a wide range of directions. It is an even greater challenge to define lava flow trajectories when an eruption lasts over several years and flows cool down, changing the surrounding topography. In this study, we test Q-LavHA, an open source plug-in that simulates lava flow inundation calculating its probability, and using Paricutin’s eruption (1943–1952) in central Mexico as a case study. We have appropriately calibrated the Q-LavHA plug-in for the Paricutin case study, which provides insights on how to better model lava flows in gentle terrain. From this work, we observe that each phase is characterized by a unique set of parameters requiring a careful calibration and that low-relief topographies require special consideration. Our findings could be useful for real-time hazard evaluation in future volcanic scenarios in the Michoacán–Guanajuato volcanic field and elsewhere, where new monogenetic eruptions similar to Paricutin can be expected., This research was supported by the Government of Spain through “Juan de la Cierva” postdoctoral fellowship awarded to L. Becerril; NSF EAR 1019798 (2014–2016) and a UNAM-DGAPA postdoctoral fellowship (2018–2019) granted to P. Larrea; National Science Foundation (NSF) EAR grant #1019798 awarded to E. Widom. Consejo Nacional de Ciencia y Tecnología (CONACyT-167231) and Dirección General de Asuntos del Personal Académico (UNAM-DGAPA-IN-104221) granted to C. Siebe; and VeTOOLS and EVE projects funded by the European Commission (EC ECHO SI2.695524 and 826292EC ECHO SI2.695524) granted to J. Martí.

Hazard assessment of remote volcanic islands provides many challenges compared to other volcanoes and volcanic fields. Here we present the first systematic volcanic hazard assessment of Jan Mayen Island, a remote island located in the North-Atlantic Ocean and home to the northernmost active subaerial volcano in the world (Beerenberg Volcano), and we discuss some of the challenges and characteristics of performing a volcanic hazard assessment of a remote volcanic island. Jan Mayen has had at least five eruptions since its discovery at the start of the 17th century. Its Holocene volcanism is mainly characterized by eruptions with styles ranging from Hawaiian to Strombolian, but also by lava domes and Surtseyan eruptions. Based on field data, remote images, topographic data, past data, and computer simulations, our study evaluates the spatial probability of new vents opening, estimates eruption recurrence rates, simulates various eruption scenarios, and produces hazard maps for the different scenarios. This work shows where the hazards of ash fall, and lava flows are more likely to affect the built infrastructure on Jan Mayen Island. This hazard assessment will assist emergency planning and the determination of future land use on the island., This study was part of EG’s Ph.D. project and was financed by the Centre for Geobiology at the University of Bergen and the Nordic Volcanological Center at the University of Iceland. This paper has been written while the lead author has been employed at UiT the Arctic University of Norway. This study has also been part of the VeTools and EVE projects (EC ECHO Grants SI2.695524 and 826292).

Understanding the relationship cause/effect between tectonic earthquakes and volcanic eruptions is a striking topic in Earth Sciences. Volcanoes erupt with variable reaction times as a consequence of the impact of seismic waves (i.e. dynamic stress) and changes in the stress field (i.e. static stress).In2012, three large(Mw≥7.3)subductionearthquakes struck Central Americawithin a period of 10 weeks;subsequently, some volcanoesin the regionerupted a few days after, whileotherstook months or even years to erupt. Here, we show thatthese threeearthquakes contributed to the increase in the number of volcanic eruptionsduring the 7 years that followed these seismic events. We found that onlythosevolcanoes that were already in a critical state ofunrest eventually erupted, which indicates that the earthquakes only prompted the eruptions. Therefore, we recommend the permanent monitoring of active volcanoes toreveal which are more susceptible to culminate into eruption in the aftermath of the next large-magnitude earthquake hits a region., Funding was provided by Japan International Cooperation Agency (JICA) and Istitute Nazionale di Geofisica e Vulcanologia (INGV).

Volcanic zones are important geoheritage sites. Active volcanic fields are of special interest because they allow to observe the complex and interesting stratigraphic relationships that often characterise their products and processes, as well as landscapes of unusual beauty. These geological sites enable visitors to appreciate the full complexity of volcanic activity and the importance of the geoheritage values that should be preserved. To ensure a correct preservation of these zones while opening them up to visitors, management plans should establish and consolidate a network of outcrops that allow visitors to get to know the area in question and preserve its geological heritage and the social and economic dynamism. In La Garrotxa Volcanic Field, most of which is protected by a natural park, a new methodology has been created to identify the sites of greatest geological interest and, above all, those that exemplify the diversity of eruptive styles and volcanic products and landforms in the area. Taking into account the most relevant management requirements (conservation and dissemination), in 1994 a total of 60 outcrops were classified as points of geological interest of the area. In this study we further present a specific methodology to select the most suitable sites for the preservation of the main volcanological features of La Garrotxa Volcanic Field. A group of 12 sites were selected from the initially identified outcrops and included in an itinerary as the most representative geological and pedagogical sites while also bearing in mind their ease of access and preservation and the possible impact of visitors (e.g. erosion). The following five criteria were considered when restoring these outcrops: integration into the landscape, consolidation of their geology, regulation of visits, the mitigation of risk, and the participation of the people that live in the area.

San Miguel volcano (or Chaparrastique), one of El Salvador's most active volcanoes, has erupted 28 times in the past 431 years (historical period). The majority of historical eruptions have been Strombolian (VEI 1–2) that have occurred from the central vent and have generated ashfall and ballistics, but some of them (8) have been effusive flank eruptions, mainly producing lava flows of basaltic and basaltic-andesite composition. Secondary lahars generated by remobilization of the young tephra are also common at San Miguel volcano. Using the information for these historical as well as prehistoric eruptions and applying probabilistic tools designed for volcanic-hazards assessment, we simulated: (1) the five most likely scenarios (ashfall scenarios, local-moderate extent, and VEI 1–2); (2) other probable scenarios related to lava flows, based on the historical record of the volcano; (3) other possible scenarios related to pyroclastic density currents (PDCs) with similar characteristics to those that occurred during its eruptive history; and (4) the most hazardous scenarios (ashfall, lava flow, PDC) that have been identified from its prehistoric geological record. Finally, we construct a qualitative integrated volcanic hazard map through the combination of the simulated scenarios. This study was developed with the aim of improving the existing volcanic-emergency plan. It should serve to improve the collaboration and coordination between scientists, the national observatory (OA-MARN), and the civil protection agency of San Miguel municipality, and will help to strength this cooperation to respond effectively to future volcanic crises., This research was partially funded by Grant I-COOPA20161 (CSIC).

We present a detailed stratigraphy of the Coranzulí caldera-forming deposits. This caldera, located in the Altiplano-Puna Volcanic Complex (Central Andes), generated four ignimbrite deposits with similar field characteristics and facies that differ from each other in, above all, the nature of the lithic fragments they contain. Three different lithofacies (fine-grained cross-stratified facies, massive lithic breccia facies and massive ignimbrite facies) are found in all the ignimbrite deposits, which occasionally also contain a lenticular lithic-rich facies and/or a pumice-rich facies. These field characteristics and, in particular, local deposit thicknesses were used to develop a theoretical model of the dynamics and emplacement mode of the Coranzulí pyroclastic flows. Our results show that these ignimbrites were emplaced by dense pyroclastic density currents subjected to high accumulation rates and velocities, thereby indicating rapid en masse emplacement that was also influenced by local paleotopography as deduced from facies analysis., This work was supported by Agencia Nacional de Promoción Científica y Técnica (PICT-2012-419; PICT-2017-2798; PICT-2017-1928) and the Consejo Nacional de Investigaciones Científicas y Técnicas (PUE 2016-2021), Argentina. SG is grateful to Elena López, Albano Floridia and Emanuel Ramos for their assistance in the field and Valmir da Silva Souza for the helpful discussions. JM is supported by the Spanish Grant CGL2017-84901-C2-1.

Anticipating volcanic eruptions at central volcanoes require knowing how magma chambers prepare for new eruptions. Pre-eruptive processes that occur in such magma chambers are recorded in the products of these eruptions, so their characterisation in terms of magma composition and physics offers the clues to understand past eruptions and predict future ones. Here, we study the very well preserved pyroclastic succession of El Palomar Member (712 ± 41 ka), in Las Cañadas caldera, Teide, Canary Islands. This deposit resulted from a single explosive eruption of a phonolitic magma that started with a sustained eruption column (sub-plinian or plinian) that formed a massive, 40 m thick non-welded fallout deposit, progressively changing into a lower intensity fire fountain that deposited a 25 m thick fallout succession of non-welded to strongly welded pumices. Stratigraphic and petrological data suggest that this eruption was related to a thermally-compositionally zoned and relatively shallow magma chamber in which the arrival of a hotter and more mafic magma rapidly triggered the eruption. The studied deposit shows how this zoned structure was maintained during the whole process, which allows one to reconstruct what happened during the eruption. Comparison of this eruption with the current situation at Teide volcano alerts on the potential rapid preparation for new eruptions in the case that sufficient phonolitic magma was available in the shallow plumbing system of this active volcano if new inputs of deeper magma take place.

The correct identification and interpretation of unrest indicators is useful for forecasting volcanic eruptions, delivering early warnings, and understanding the changes occurring in a volcanic system prior to an eruption. Such indicators play an important role in upgrading previous long-term volcanic hazard assessments and help explain the complexities of the preceding period of eruptive activity. In this work, we present a retrospective analysis of the 2011 unrest episode on the island of El Hierro, Canary Islands, that preceded a submarine eruption. We use seismic and surface deformation monitoring data to compute the susceptibility analysis (QVAST tool) and to study the evolution over time of the unrest (ST-HASSET tool). Additionally, we show the advantages to be gained by using continuous monitoring data and hazard assessment e-tools to upgrade spatiotemporal analyses and thus visualize more simply the development of the volcanic activity., This research was funded by the European Commission (EC ECHO Grant SI2.695524: VeTOOLS). Joan Martí is grateful for the MECD (PRX16/00056) grant.

Deception Island (South Shetland Islands) is one of the most active volcanoes in Antarctica, with more than 20 explosive eruptive events registered over the past two centuries. Recent eruptions (1967, 1969, and 1970) and the volcanic unrest episodes that happened in 1992, 1999, and 2014–2015 demonstrate that the occurrence of future volcanic activity is a valid and pressing concern for scientists, technical and logistic personnel, and tourists, that are visiting or working on or near the island. We present a unifying evolutionary model of the magmatic system beneath Deception Island by integrating new petrologic and geochemical results with an exhaustive database of previous studies in the region. Our results reveal the existence of a complex plumbing system composed of several shallow magma chambers (≤10 km depth) fed by magmas raised directly from the mantle, or from a magma accumulation zone located at the crust-mantle boundary (15–20 km depth). Understanding the current state of the island’s magmatic system, and its potential evolution in the future, is fundamental to increase the effectiveness of interpreting monitoring data during volcanic unrest periods and hence, for future eruption forecasting. © 2019, The Author(s)., This research was supported by the MICINN grants RECALDEC (CTM2009–05919-E/ANT) and PEVOLDEC (CTM2011–13578-E/ANT), and the POSVOLDEC(CTM2016–79617-P)(AEI/FEDER, UE) and VOLCLIMA(CGL2015–72629-EXP)(AEI) projects. A.G. is grateful for her Ramón y Cajal contract (RYC-2012–11024). Analyses of stable isotopes were funded by the grant Programa Propio I (Usal-2014) through A.M.A-V.

The geoheritage of the Central Spanish Volcanic Region (Ciudad Real) has been severely affected by open pit mining since the beginning of the twentieth century until 2017. Field work, photointerpretation of aerial images, and consultation of the Mining Cadaster of the Spanish Geological Survey (IGME) have been used to characterize the impact that open-pit mining has on the geomorphology of this volcanic area. As a result of this intense mining activity, uninterrupted over the course of a century, 18.76 million tons of basalt and more than 16.11 million tons of scoriaceous deposits (considered as industrial minerals) have been extracted, which has caused irreversible damage to the region’s geoheritage. Some thirty volcanoes have been destroyed, with cinder cones and exogenous domes being particularly affected. Currently, the validity of this mining exploitation system represents a serious threat to the conservation of the rich volcanic heritage of the area. Therefore, urgent measures are needed to rationalize the management of natural resources, namely, to make their use and preservation compatible for the future generations., JM is grateful for a stay at the Ludwig-Maximilians-Universität München (LMU), supported by the Center for Advanced Studies (CAS, LMU).

The Acoculco caldera complex (ACC) is located in the eastern part of the Trans-Mexican Volcanic Belt in the northern part of the State of Puebla. The complex sits at the intersection of two regional fault systems with NE-SW and NW-SE orientations. The ACC was built atop Cretaceous limestones, the Zacatán basaltic plateau of unknown age, early Miocene domes (~12.7–10.98 Ma), and Pliocene lava domes (~3.9–3 Ma). Detailed field mapping and stratigraphy studies complemented by 40Ar/39Ar and 14C dating allowed the division of the ACC volcanic succession into 30 volcanic units. Based on the new results and previous studies, the ACC eruptive chronology was grouped in four eruptive phases: syn-caldera, early post-caldera, late post-caldera, and extra-caldera. Inception of the ACC volcanism began around 2.7 Ma with the dispersion of an andesitic ignimbrite followed by the collapse of the magma chamber roof as attested by the presence of a lithic breccia in isolated parts of the caldera rim. The collapse produced a 18 × 16 km caldera depression which was partly filled by the ignimbrite (total volume of ~127 km3) followed by the establishment of an intracaldera lake of unknown total extension. Early post-caldera collapse activity (2.6–2.1 Ma) was restricted within the caldera producing 27 km3 of lava flows and domes dominantly of basaltic trachyandesite to basaltic composition. Late post-caldera collapse activity (2.0-1 km hosted in the Cretaceous limestones. These bodies might represent a series of horizontal mafic intrusions located at different depths that provide the energy that maintains the Acoculco geothermal system active., This study was partially funded by the Centro Mexicano de Innovación en Energía Geotérmica (CeMIE-Geo) project P15 and GEMex 4.4. to J.L. Macías. J. Marti is grateful for the MECD, Spain (PRX16/00056) grant.

Recent studies on intraplate volcanic islands reveal that magma ascends sub-vertically through these volcanic edifices, following well-defined zones in the lithospheric mantle and oceanic crust, and occasionally suffering lateral propagation along rift zones when it reaches very shallow depths. Visualizing the internal structure of the shallowest part of such magma plumbing systems is crucial to understanding magma transport and the location of basaltic volcanism in these volcanic environments. Tenerife (Canary Islands) is a very good example of an intraplate volcanic island, in which the distribution of basaltic volcanism includes well-defined rift systems, and wider monogenetic fields where cinder cones form clusters along different tectonic alignments. In order to characterize the structure of the uppermost part of the basaltic plumbing system of Tenerife, we conducted a detailed gravimetric study of the north-western, central, and southern sectors of the island. We developed a 3D density contrast model of the subsoil based on the application of a genetic algorithm for the inversion of gravity data. The results of our inverse modelling suggest that the observed gravimetric anomalies below the northwestern rift zone are shallow and aligned parallel to this structure. This is consistent with a shallow character for the rift system and a lateral migration of magma along it that comes from a deeper zone located towards the east of this rift zone. Conversely, the anomalies located in the south are also shallow but are distributed along more than one alignment and are connected to much deeper sub-vertical similar density anomalies. These results support the existence of several main channels at the north and south of the island that allow the ascent of deep basaltic magma to shallower zones of Tenerife. There, magma may be either caught by the rifts systems, being distributed laterally and occasionally erupting, or may continue its ascent to the surface using a secondary system of shallow fractures that dominates the southern part of Tenerife. The results of our inverse model also offer new insights on others aspects of the internal structure of Tenerife, such as the distribution of the basaltic shield or that of Las Cañadas caldera. © 2019 Elsevier B.V., Joan Martí was funded by the MECD ( PRX16/00056 ) grant. This work was partially supported by the Instituto Geográfico Nacional of the Spanish Ministerio de Fomento and through projects CGL2014-53044-R and CGL2015-63799-P of the Spanish Ministry of Economy and Competitiveness .

The Las Cañadas caldera is one of the best exposed volcanic calderas in the world and one of the few known evolved alkaline volcanoes. It truncates the pre-Teide-Pico Viejo central volcanic edifice, the Las Cañadas edifice, which started to take shape at the end of the formation of a large basaltic shield that forms the main part of island of Tenerife. Historically, the origin of the Las Cañadas caldera has been controversial, as it has been interpreted as the result of either multiple vertical collapses or due to a giant sector collapse. The available stratigraphical, structural, volcanological, geochronological, and geophysical data, as well as its comparison to other well-known collapse calderas should not offer any doubt as to its direct relationship with a long history of phonolitic explosive volcanism. However, the existence of large landslide events on Tenerife, which have significantly modified the flanks of the Las Cañadas volcano, have also been used as a potential explanation for the origin of the Las Cañadas depression. This contribution reviews the available information on the Las Cañadas caldera, the causes of this controversy, and rationalises the most plausible explanation for the origin of Las Cañadas caldera based on the current evidence gathered from all previous studies. © 2019 Elsevier B.V., I also thank Teide National Park for giving permission to undertake this research, which has been funded, among others by the EC grants TEIDE: European Laboratory Volcano, ERUPT, EXPLORIS (EVR1-CT-2002-40026), and VUELCO (FP7-ENV-2011 282729), and the Spanish grants MCyT TECTOTENE, MCyT FONOTEN, MEC TEGETEIDE (CGL2004-21643-E), MEC TENERISK (CGL-2006-13830), MEC PR-2006-0499, MICINN (CGL2010-11983-E), EXPLOTEI MICINN (CGL2008-04264), and MEC (CGL-2004-21247).