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Determining SO 2 emission time-series from explosive eruptions can provide important insights into the driving magmatic processes, however accurate measurements are difficult to collect. Satellite-based platforms provide SO 2 imagery, however translating this to the altitude- and time-resolved emission history required to unravel volcanic processes is a major challenge. This means SO 2 emission time-series are rarely quantified for major eruptions, producing a gap in our understanding of explosive volcanism. Here, we combine SO 2 imagery collected by the TROPOspheric Monitoring Instrument (TROPOMI) with PlumeTraj, a back-trajectory analysis toolkit, to reconstruct the SO 2 emission prior to, and during, the explosive eruption of La Soufrière volcano, St Vincent, in April 2021. Precursory SO 2 emissions were quantified the day before the eruption, with emission rates in agreement with ground-based measurements. We estimate initial magma sulfur contents by comparing the measured SO 2 emissions with erupted magma volumes, finding that the initial explosion was sulfur poor (730 ppm S) compared to the main eruption phase (up to 3400 ppm S). This suggests that the initial explosion cleared old, previously degassed magma resident in the shallow plumbing system, followed by the eruption of the main, mostly un-degassed magma source.

This chapter reviews the development of research in face recognition. In particular, it describes the close association between theoretical and practical advances in the field. Early work on eyewitness testimony brought the study of memory and perception to important real-world problems, and led to some changes in forensic practice—mostly changes designed to avoid unjust judicial outcomes. More recently, a focus on face matching (e.g. checking photo identification or examining CCTV) has highlighted some important unsolved problems in our understanding of face perception. In particular, the role of familiarity is critical—people are remarkably good at recognizing other people they know, even in difficult circumstances, but are (perhaps surprisingly) bad at recognizing or matching previously unfamiliar faces. The chapter describes the findings leading to these conclusions and outlines the challenges remaining. It concludes that, while psychological research has led to some improved practices, theoretical progress has benefited enormously from a consideration of practical problems of face perception that we encounter every day.

Antuco (37.4°S, 71.4°W; Chile) is a dominantly basaltic stratovolcano whose original ~ 3300 m altitude main cone experienced a catastrophic sector collapse at ~ 7.1 cal ka BP, producing a volcanic debris avalanche deposit (VDAD) with hummocky surface and ~ 6.4 km3 of volume. We carried out geological studies of its debris avalanche deposit, which was distributed to the W and displays a longitudinal facies transformation from edifice’s megablocks and block to mixed facies in distal areas (up to 25 km from the scar). Our observations support the behavior of the avalanche beginning as a translational slide, and then as plug flow when confined within the Laja River valley. Clay abundance and high content of hydrothermally altered material may suggest active participation of water; flow velocities are estimated to ~100 m s−1. We primarily identify the steep-sided flanks of the cone, and hydrothermal alteration promoted the edifice instability, while basement seismogenic structures may have ultimately triggered the landslide. Subsequent landslide-led events include the transformation of the volcanic activity with explosive eruptions producing a sequence of dilute pyroclastic density currents (PDCs) ending ~3.4 ky BP, and extensive lava effusion rapidly reconstructing the collapsed edifice. Moreover, the Antuco VDAD also blocked the natural output of the Laja Lake, increasing its level by ~200 m and then triggering cataclysmic outburst floods by dam rupture, preserved as high-energy alluvial beds with ages between 2.8 and 1.7 ky BP. The Antuco constitutes an excellent example of a critical chain of events initiated by a stratovolcano lateral collapse and warns for detailed hazard investigations to better comprehend its related impacts.

Investigations into human cognition typically control variables tightly in the laboratory or relinquish systematic control in field studies. Virtual Reality (VR) can provide an intermediate approach by facilitating research with complex but controlled environments. However, understanding of the correspondence between VR and laboratory paradigms is still limited. This study addresses this issue by comparing established laboratory tests of face identification with passport control at a VR airport. We show that test characteristics transcend comparison of the laboratory tests and VR and demonstrate consistent correlations between these tasks. However, person identification in VR was also marked by bias to accept mismatching identities. These findings support correspondence between laboratory tests of face perception and VR but also highlight the importance of understanding human behaviour under more complex conditions. This problem arises in many areas of psychology, and our study shows that VR offers a solution by providing complex but controlled environments.

The geological carbon cycle has played a key role in controlling climate throughout Earth's history. For the last ∼3 billion years plate tectonics has driven subduction. Subducted slabs have transported CO2 from the lithosphere, hydrosphere, and atmosphere into the Earth, from where it may be released back to the surface through processes such as arc volcanism or can be stored in the deep interior over geological time. Carbonate-bearing sediments and basalts of altered oceanic crust are the primary media by which carbon is subducted. Therefore, quantifying the depth and amount of CO2 released from different carbonate-bearing lithologies during subduction is fundamental to understanding whether CO2 is recycled through arc volcanism or buried in the mantle. The magnitude of CO2 released from subducting slabs at fore- and sub-arc depths is controlled by processes including ocean crust alteration (i.e., carbonation), metamorphic decarbonation, carbonate dissolution and slab-melting. However, the relative contribution of these processes to overall slab decarbonation is still debated, and will be complex given the variety of sedimentary lithologies and subduction geodynamics. Here, we present a global arc-by-arc lithology-specific analysis of the magnitude of slab CO2 released purely by metamorphic decarbonation of carbonate-bearing sediment and basalt during subduction of altered oceanic crust, using a thermodynamically rigorous model. We find that metamorphic decarbonation is highly efficient in low carbonate sediments, such as carbonated clay, and in carbonated basalts of altered oceanic crust, causing all of their CO2 to be removed. Sediments with medium and higher carbonate contents, such as chalk and limestone, are only partially decarbonated, but the combination of metamorphic decarbonation and carbonate dissolution promotes efficient carbon loss. Together they can explain observed magmatic CO2 emissions in carbonate-rich arcs. Warm slabs, such as Mexico and Cascadia, produce complete metamorphic decarbonation of carbonate minerals beneath fore-arcs. Under more common cold and intermediate thermal regimes metamorphic decarbonation of carbonate minerals occurs at depths between ∼80 and 170 km (∼2.3 to 5.5 GPa) promoting CO2 input into the mantle sources of volcanic arcs. Overall, our results demonstrate that sub-arc decarbonation is typically considered an important potential source of slab-derived CO2, which needs to be considered together with carbonate dissolution to explain observed volcanic CO2 emissions. In many arcs the modelled CO2 flux from sediment and basalts of altered oceanic crust into the wedge exceeds the observed CO2 output suggesting that the mantle wedge and arc lithosphere may sequester some CO2.

Supplemental material, sj-pdf-1-qjp-10.1177_17470218231169952 for Perception of threat and intent to harm from vocal and facial cues by James Tompkinson, Mila Mileva, Dominic Watt and A Mike Burton in Quarterly Journal of Experimental Psychology

Human faces and voices are rich sources of information that can vary in many different ways. Most of the literature on face/voice perception has focused on understanding how people look and sound different to each other (between-person variability). However, recent studies highlight the ways in which the same person can look and sound different on different occasions (within-person variability). Across three experiments, we examined how within- and between-person variability relate to one another for social trait impressions by collecting trait ratings attributed to multiple face images and voice recordings of the same people. We find that within-person variability in social trait evaluations is at least as great as between-person variability. Using different stimulus sets across experiments, trait impressions of voices are consistently more variable within people than between people-a pattern that is only evident occasionally when judging faces. Our findings highlight the importance of understanding within-person variability, showing how judgments of the same person can vary widely on different encounters and quantify how this pattern differs for voice and face perception. The work consequently has implications for theoretical models proposing that voices can be considered "auditory faces" and imposes limitations to the "kernel of truth" hypothesis of trait evaluations. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Knowledge of sulfur dioxide layer height (SO2 LH) is important to understand volcanic eruption processes, the climate impact of SO2 emissions and to mitigate volcanic risk for civil aviation. However, the estimation of SO2 LH from ground-based instruments is challenging in particular for rapidly evolving and sustained eruptions. Satellite wide-swath nadir observations have the advantage to cover large-scale plumes and the potential to provide key information on SO2 LH. In the ultraviolet, SO2 LH retrievals leverage the fact that, for large SO2 columns, the light path and its associated air mass factor (AMF) depends on the SO2 absorption (and therefore on the vertical distribution of SO2), and SO2 LH information can be obtained from the analysis of measured back-scattered radiances coupled with radiative transfer simulations. However, existing algorithms are mainly sensitive to SO2 LH for SO2 vertical columns of at least 20 DU. Here we develop a new SO2 LH algorithm and apply it to observations from the high-spatial-resolution TROPOspheric Monitoring Instrument (TROPOMI). It is based on an SO2 optical depth look-up table and an iterative approach. The strength of this scheme lies in the fact that it is a Covariance-Based Retrieval Algorithm (COBRA; Theys et al., 2021). This means that the SO2-free contribution of the measured optical depth is treated in an optimal way, resulting in an improvement of the SO2 LH sensitivity to SO2 columns as low as 5 DU, with a precision better than 2 km. We demonstrate the value of this new data through a number of examples and comparison with satellite plume height estimates (from IASI and CALIOP), and back-trajectory analyses. The comparisons indicate an SO2 LH accuracy of 1–2 km, except for some difficult observation conditions, in particular for optically thick ash plumes or partially SO2-filled scenes.

What constitutes a “threatening tone of voice”? There is currently little research exploring how listeners infer threat, or the intention to cause harm, from speakers’ voices. Here, we investigated the influence of key linguistic variables on these evaluations (Study 1). Results showed a trend for voices perceived to be lower in pitch, particularly those of male speakers, to be evaluated as sounding more threatening and conveying greater intent to harm. We next investigated the evaluation of multimodal stimuli comprising voices and faces varying in perceived dominance (Study 2). Visual information about the speaker’s face had a significant effect on threat and intent ratings. In both experiments, we observed a relatively low level of agreement among individual listeners’ evaluations, emphasising idiosyncrasy in the ways in which threat and intent-to-harm are perceived. This research provides a basis for the perceptual experience of a “threatening tone of voice,” along with an exploration of vocal and facial cue integration in social evaluation.

Volcanic plumes are common and far-reaching manifestations of volcanic activity during and between eruptions. Observations of the rate of emission and composition of volcanic plumes are essential to recognize and, in some cases, predict the state of volcanic activity. Measurements of the size and location of the plumes are important to assess the impact of the emission from sporadic or localized events to persistent or widespread processes of climatic and environmental importance. These observations provide information on volatile budgets on Earth, chemical evolution of magmas, and atmospheric circulation and dynamics. Space-based observations during the last decades have given us a global view of Earth's volcanic emission, particularly of sulfur dioxide (SO2). Although none of the satellite missions were intended to be used for measurement of volcanic gas emission, specially adapted algorithms have produced time-averaged global emission budgets. These have confirmed that tropospheric plumes, produced from persistent degassing of weak sources, dominate the total emission of volcanic SO2. Although space-based observations have provided this global insight into some aspects of Earth's volcanism, it still has important limitations. The magnitude and short-term variability of lower-atmosphere emissions, historically less accessible from space, remain largely uncertain. Operational monitoring of volcanic plumes, at scales relevant for adequate surveillance, has been facilitated through the use of ground-based scanning differential optical absorption spectrometer (ScanDOAS) instruments since the beginning of this century, largely due to the coordinated effort of the Network for Observation of Volcanic and Atmospheric Change (NOVAC). In this study, we present a compilation of results of homogenized post-analysis of measurements of SO2 flux and plume parameters obtained during the period March 2005 to January 2017 of 32 volcanoes in NOVAC. This inventory opens a window into the short-term emission patterns of a diverse set of volcanoes in terms of magma composition, geographical location, magnitude of emission, and style of eruptive activity. We find that passive volcanic degassing is by no means a stationary process in time and that large sub-daily variability is observed in the flux of volcanic gases, which has implications for emission budgets produced using short-term, sporadic observations. The use of a standard evaluation method allows for intercomparison between different volcanoes and between ground- and space-based measurements of the same volcanoes. The emission of several weakly degassing volcanoes, undetected by satellites, is presented for the first time. We also compare our results with those reported in the literature, providing ranges of variability in emission not accessible in the past. The open-access data repository introduced in this article will enable further exploitation of this unique dataset, with a focus on volcanological research, risk assessment, satellite-sensor validation, and improved quantification of the prevalent tropospheric component of global volcanic emission. Published version Initial implementation of the network was funded by the EU FP6 NOVAC project (https://cordis.europa.eu/ project/rcn/75513/factsheet/en, last access: 1 October 2020). Recent funding for this work was provided by the Alfred P. Sloan Foundation’s Deep Carbon Observatory programme (https://deepcarbon. net/, last access: 1 October 2020), Chalmers University of Technology, the Swedish National Space Agency (career grant no. 149/18), and the ECMWF CAMS_81 Global and Regional Emissions project. The authors are thankful for the valuable support from the USGS–USAID Volcano Disaster Assistance Program (https: //volcanoes.usgs.gov/vdap/, last access: 1 October 2020) provided to NOVAC since 2015.

Recognizing a face as familiar is essential in our everyday life. However, 'familiarity' covers a wide range - from people we see every day to those we barely know. Although face recognition is studied extensively, little is known about how the degree of familiarity affects neural face processing, despite the critical social importance of this dimension. Here we report the results of a multivariate cross-classification EEG experiment, where we study the temporal representational dynamics of the degree of familiarity. Participants viewed highly variable face images of 20 identities. Importantly, we measured face familiarity using subjective familiarity ratings in addition to testing explicit knowledge and reaction times in a face matching task. A machine learning algorithm, trained to discriminate familiar and unfamiliar faces from a separate study, was used to predict the degree of face familiarity from the pattern of the EEG data. We found that the neural representations of the degree of familiarity emerge between 400 - 600 msec post-stimulus onset for famous persons. The correlation between decoding performance and behavioral familiarity was more reliable, occurred earlier and lasted longer when personally familiar and viewers' own faces were included in the analysis. Our findings provide new insights into how the brain represents faces with various degrees of familiarity and show that the degree of familiarity can be decoded reliably from the EEG at a relatively late time window. These results support the idea that representations of familiar faces form part of a general neural signature of the familiarity component of recognition memory processes.

Fissure eruptions are a pollution hazard due to their emissions of gas and aerosol particulate matter (PM) into the lower troposphere, which elevates pollutant concentrations at ground level. Alongside major gas species (e.g., H2O, SO2, CO2) and minute amounts of ash, fissure eruptions emit volatile trace elements including metals and metalloids, typically transported in the atmosphere as fine particulates.The 2021 Fagradalsfjall fissure eruption in Iceland presented a unique opportunity to better understand volatile emissions and their spread in the atmosphere. During a 5-week campaign inMarch-April 2021, we sampled the plumes from the active vents and the lava flows using ground-based instruments and Unmanned Aerial System (UAS). Size-resolved major (including sulfate and chloride) and trace element aerosol chemistry were analysed using ICP-MS and ion chromatography. We compare the emission rate and magmatic volatility of trace elements between the crater and the lava degassing; and with that of other eruptions globally.The volcanic plume was also sampled in several downwind areas between 3 and 30 km distance from the eruption site. Using this network, we captured temporal and spatial changes in the major and trace element chemistry of the volcanic plume as it aged.

On September 19th 2021 a fissure eruption started on the Cumbre Vieja rift on La Palma, Canary Islands. The fissure eruption rapidly evolved into a cone-forming eruption, with several summit vents producing explosive activity and lava jetting, while lava spattering and effusive activity occurred at/from lower flank vents.We used open-path Fourier transform infrared spectroscopy (OP-FTIR) to measure the chemical composition of degassing associated with both explosive and effusive activities, using absorption spectra of the radiation emitted by molten lava and incandescent ash. Measurements were performed daily since October 2nd until the end of the eruption (mid-December), from different sites and at distance range of 0.6 to 5 km from the vents. They allowed us to retrieve the molar proportions of H2O, CO2, SO2, HCl and CO in gas emissions from the different vents and different activities.In this work, we report the main results obtained for the gas compositions, their spatial and temporal evolution during the eruption, the influence of fragmentation (ash) on the degassing of HCl, and the gas-magma redox state during the La Palma 2021 eruption.

Ground and satellite SO2 measurements have been extensively compared for high altitude volcanic emissions but far less for grounded plumes. The 2018 and 2020 Kilauea eruptions offered perfect opportunities to compare our TROPOMI results with ground measurements. Not only is Kilauea a very well monitored volcano, so the ground measurements are abundant and reliable, the SO2 plumes were big enough to be picked up by satellite. We compared the results to assess the efficacy of TROPOMI as a remote sensing tool applied at low-lying SO2 plumes. We concluded that the fluxes for both agreed provided the wind speed is the same for both. Remote sensing is therefore an important tool for effusive eruption monitoring and could be used on its own at remote volcanoes where ground instruments are sparse or lacking.

Volcanic gas emissions are an integral part of volcano monitoring around the world and can be interpreted to understand the state of a volcano and the evolution of an individual eruption. The low ambient concentrations of SO2 make it an ideal monitoring candidate.Throughout the 2021 eruption of Cumbre Vieja, La Palma (Spain), observations of SO2 emissions were made using ground-based instruments, in transverse mode, static scanners and on-board drones, as well as by numerous satellite instruments. Direct comparison between satellite- and ground-based instruments is always challenging, but the long duration of the eruption and repeated measurements from both data sets made this a good candidate.Data from the Sentinel-5P instrument TROPOMI was combined with the PlumeTraj back-trajectory analysis toolkit to produce sub-daily SO2 fluxes that can be directly compared to the ground-based observations as well as other geophysical and geochemical monitoring data.The volcano produced significant volcanic ash emissions, particularly in the earlier phases of the eruption, which impacted both ground- and satellite-based measurements. This produced underestimations in the SO2loading where ash was present, impacting the proximal plume more that the distal as the ash settles out with time. This meant that traverse measurements were more impacted, leading to a disparity in the measured fluxes from ground and space. Later, when ash emissions had decreased, the agreement between the two was much improved, with trends closely replicated between the traverse and satellite fluxes.The initial estimates of the total SO2 emission from the eruption were 4.1 Mt from TROPOMI and 1.2 Mt from the traverse data.These measurements formed part of the official monitoring effort, providing insights into the eruption’s evolution and informing the civil defence response throughout the eruption.

Effusive eruptions are a significant source of volcanic volatile species, injecting various reactive and climate altering products into the atmosphere, while low-level emissions can be hazardous to human health due to the degradation of local or regional air quality. Quantification of the flux and composition of these emissions also offers an insight into the magmatic processes driving the eruption. These factors mean that gas flux measurements are a key monitoring tool for managing the response to such eruptions. The usual target species for gas flux measurements is sulphur dioxide (SO2) due to its high concentration in volcanic emissions but low ambient concentration, and its ability to be measured with UV and IR spectroscopy from both ground and space.Fagradalsfjall volcano, Iceland, underwent an effusive eruption between March – September 2021, emitting over 100 million m3 of lava and producing significant SO2 emissions. The eruption progressed through several distinct phases in eruptive style, with different surface activity and gas emission behaviour for each. Satellite instruments have not traditionally been used for monitoring emissions from effusive eruptions such as this, as they often lack the spatial or temporal resolution to detect and quantify low-level effusive emissions. However, the launch of ESA’s Sentinel-5P, carrying the TROPOMI instrument, in October 2017 opened the door for such measurements, offering a step change in sensitivity to tropospheric emissions over previous missions.Here, we will present measurements of altitude- and time-resolved SO2 fluxes from Fagradalsfjall by combining TROPOMI observations with a back-trajectory analysis toolkit called PlumeTraj. We compare the emissions with other geophysical monitoring streams throughout the eruption and explore changes across the different phases of the eruption. This will demonstrate the ability of TROPOMI and PlumeTraj for quantifying intra-day, low-level SO2 emissions and highlight the potential insight these measurements can provide for future effusive eruptions.

During September-December 2021, the Cumbre Vieja eruption (La Palma, Canary Islands) was characterised by simultaneous explosive and effusive activity (Longpré, 2021; Pankhurst et al., 2021). The eruption produced a ~200 m high complex pyroclastic cone (Romero et al., 2022). A series of syn-eruptive lateral collapses modified the edifice morphology and caused sporadic breaching towards the west-northwest, influencing the nature and distribution of eruptive hazards.We documented these destructive events using tremor and seismic data, as well as direct visual and thermal observations of the eruptive activity. In addition, UASs were used for aerial surveys and DEM generation in late September 2021. Field descriptions of the resulting deposits and stratigraphic sampling of tephra fallout were carried out in October and November 2021. Microanalysis of pyroclastic fragments included scanning electron microscope and electron microprobe for textural and compositional characterisation.Two classes of collapse events were observed: the first involved a substantial portion of the cone and led to its horseshoe scar morphology; the second mainly affected ramparts of pyroclasts that separated vents along the fissure. The largest breaching event, which occurred on September 25, was generated by a high eruption rate and associated rapid deposition of pyroclasts on a steep pre-eruptive surface. Smaller collapses resulted from rapid pyroclastic agglutination on the conduit/fissure.Some collapses triggered an immediate and substantial increase in the lava flux presumably through release of lava that has been stored in the vent and/or shallow plumbing system. The largest collapses produced lava flows up to 10 m thick which rafted decameter-sized chunks of the failed edifice. In some cases, these outpourings inundated residential areas. Collapses were sometimes followed by an increase in the eruption intensity, forming lava fountains up to several hundred metres in height; we infer these fountains resulted from unloading of the shallow plumbing system.The 2021 eruption of Cumbre Vieja volcano provides a rare opportunity to document recurrent, syn-eruptive collapses of the vent edifice during a cone-forming eruption, and to identify and characterise the hazards associated with this common type of activity. References:Longpré, M. A. (2021). Reactivation of Cumbre Vieja volcano. Science, 374(6572), 1197-1198. Doi: 10.1126/science.abm9423Pankhurst, et al. (2022). Rapid response petrology for the opening eruptive phase of the 2021 Cumbre Vieja eruption, La Palma, Canary Islands. Volcanica, 5(1), pp. 1–10. Doi: 10.30909/vol.05.01.0110.Romero et al. (2022). Volume and stratigraphy of the Cumbre Vieja 2021 eruption tephra fallout, La Palma Island. VMSG Virtual Annual Meeting, 10-12th January 2022, Manchester, United Kingdom.

Mafic alkali-rich magmas, such as those which form the Canary Islands, Spain, have been proposed as being CO2-rich due to low-degree partial melting and the presence of recycled oceanic crust in the mantle source region. A CO2-rich mantle source of Canary magmas has been suggested from melt inclusions study of the 2011 submarine El Hierro eruption, but this has not been verified yet by directly measuring magmatic CO2 emissions during a subaerial eruption as the last such event in the archipelago, in 1971, occurred before the advent of modern gas sensing tools. Here we report on the first results for gas emissions from the2021 eruption of Cumbre Vieja on La Palma island. We determined the chemical composition and mass flux of magmatic degassing during both effusive and explosive activities by combining direct plume measurements with MultiGas sensors from the ground, UAV and helicopter, OP-FTIR remote sensing and satellite-based (TROPOMI) SO2 flux quantification based on back-trajectory modelling. Degassing mass budgets and the magma volatile concentrations were then derived from microprobe analysis of olivine-hosted melt inclusions and comparing our gas results with best estimates of the magma extrusion rates during both explosive and effusive activities. Based on this approach we obtain a direct quantification of the initial CO2 content of the magma and of the exsolved pre-eruptive CO2 gas phase that fed the Cumbre Vieja eruption.We find unprecedentedly high CO2 content in the mantle source of La Palma magma, consistent with high volatile contents predicted from petrological analyses. Eruptions of oceanic island alkali-rich magmas produce disproportionately high CO2 emissions, highlighting the key role mantle heterogeneity plays in determining the impact of intraplate volcanism.

Tajogaite cone in the Cumbre Vieja ridge (La Palma, Canary Islands) erupted between 19 September and 13 December 2021. The tephra and lava sourced from the newly formed fissure rapidly built a pyroclastic cone. During the early days of eruption and after several small-scale landslides, the west flank of the edifice partially collapsed on 25 September, breaching the cone and emplacing a prominent raft-bearing lava flow. Our research combines direct observations, digital elevation models, thermal and visible imaging, and textural and compositional investigation of the explosive products to describe and characterize the edifice growth and collapse. The cone built over a steep slope (26°) and its failure occurred after an intense phase of lava fountaining (up to 30 m3 s−1) that produced rapid pyroclastic accumulation. We suggest that an increased magma supply, to an ascent rate of 0.30 m s−1, led to the rapid growth of the cone (at 2.4 × 106 m3 day−1). Simultaneously, the SW lava flow reactivated and formed a lava ‘seep’ that undercut the flank of the cone, triggering a lateral collapse via rotational rockslide that moved at minimum speeds of 34–70 m h−1. The lateral collapse formed a ~ 200 m wide scar, involving 5.5 × 106 m3 of material, and covered 1.17 km2 with decametric edifice portions and raft-bearing lava. The collapse produced a modest change in the vent geometry, but did not affect eruptive activity long term. A short pause in the eruption after the collapse may have been favored by rapid emptying of the shallower magma system, reducing ascent rates and increasing crystallization times. These results reveal the complex chain of events related to the growth and destruction of newly formed volcanic cones and highlight hazards when situated close to inhabited areas.