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Cinder cones are a common feature at many volcanic eruptions. Their shapes and volumes can reveal information about eruption conditions, and their geomorphological evolution shapes them and their surrounding environment. It is thus important to quantify the rate and patterns of erosion of young cinder cones. In this study, we examine the Ahmanilix cone, which formed during the 2008 eruption of Okmok volcano in the Aleutian islands region of Alaska. Ahmanilix, located on the eastern side of Okmok’s large caldera, is >250 meters tall and characterized by dramatic gullies formed by the harsh wind, snow and rain conditions typical of the Aleutians. We usd photogrammetry to create 3D models of Ahmanilix using aerial photographic surveys taken from a helicopter in 2021, 2022, 2023 and 2024. We utilize Agisoft Metashape to build point clouds, Cloud Compare to align the point clouds and build raster Digital Elevation Models (DEMs), and QGIS and Python to visualize and analyze these products. By subtracting DEM rasters we quantify year-to-year erosion. We compare our results with erosion rates estimated from satellite observations (Dai et al., 2020), identify regions dominated by erosion or deposition and correlate them with slopes and cinder lithology. Our observations can be extended to other cinder cones and help predict their geomorphological evolution. 

Humanitarian mine action (HMA) is a critically under-researched field when compared to other hazards fields of similar societal impact. A potential solution to this problem is early exposure to and engagement in the HMA field in undergraduate education. Early undergraduate education emphasizing technical and social aspects of HMA can help protect lives by building a robust pipeline of passionate researchers who will find new solutions to the global explosive ordnance (EO) crisis. Early engagement of the next generation of HMA researchers and policy makers can occur through various classroom experiences, undergraduate research projects, and public outreach events. These include but are not limited to course-based undergraduate research experiences (CUREs); presenting research results at local, national, and international conferences; dissemination in edited and peer-reviewed publications; local community events; and through social media outreach. Early engagement, active guidance, and mentorship of such students by mid-career and experienced HMA scholars and practitioners could dramatically reduce the learning curve associated with entry into the HMA sector and allow for more fruitful long-term collaboration between academic institutions, private industry, and leading nongovernmental organizations (NGOs) operating across different facets of HMA. 

Abstract Most lava flows carry bubbles and crystals in suspension. From earlier works, it is known that spherical bubbles increase the effective viscosity while bubbles deformed by rapid flow decrease it. Changes in the spatial distribution of bubbles can lead to variable rheology and flow localization and thus modify the resulting lava flow structure and morphology. To understand the roles of bubble and solid phase crystal distributions, we conducted a series of analog experiments of high bubble fraction suspensions. We poured the analog lava on an inclined slope, observed its shape, calculated the velocity field, and monitored its local thickness. A region of localized rapid flow and low vesicularity, whose thickness is thinner than the surrounding area, develops at the center of the bubbly flows. These features suggest that the locally higher liquid fraction decreases the effective viscosity, increases the fluid density, and accelerates the flow. We also found that a halted particle‐bearing bubbly flow can resume flowing. We interpret this to result from the upward vertical separation of bubbles, which generates a liquid‐rich layer at the bottom of the flow. In our experiment, bubbles are basically spherical and decrease the flow velocity, while our estimate suggests that bubbles in natural lava flows could increase or decrease flow velocity. Downstream decreases in flow velocity stops the bubble deformation and can cause a sudden increase of effective viscosity. The vertical segregation of the liquid phase at the slowed flow front may be a way to generate a cavernous shelly paho’eho’e.