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Allan Lerner


I am a research geologist and geochemist based at the USGS Cascades Volcano Observatory. I use volcanic gas geochemistry and igneous petrology to monitor volcanic activity and better understand the behavior of magmatic volatiles. My work centers around measuring volcanic gases, and melt and fluid inclusions within minerals.

I work on US volcanoes as part of the USGS Volcano Emissions Project and internationally with the USAID-USGS Volcano Disaster Assistance Program (VDAP) utilizing in situ gas sampling (physically collecting and analyzing gases) and remote sensing (e.g., ultraviolet spectroscopy) of volcanic gases to characterize emissions. 

Changes in volcanic gases being emitted from volcanoes can presage volcanic unrest and possible eruptions. Gases are therefore an important monitoring tool for tracking volcanic activity. I particularly focus on linking gas measurements to petrologic studies (e.g., melt and fluid inclusions) to better understand volcanic degassing processes.

My work with the USGS spans from Alaska's Aleutian Islands to Hawaii, the Cascades, and Yellowstone. I also work with VDAP to help our international partners with volcanic gas monitoring in many countries around the world. I am heavily involved in the Network for Observation of Volcanic and Atmospheric Change (NOVAC), a global community of volcano observatories and research institutions that runs the largest volcanic gas monitoring network in the world.