Relating the composition and mass flux of volcanic gas emissions with eruptive activity at Bezymianny volcano from 2007 - 2010

Bezymianny volcano, Kamchatka, Russia, is one of the world’s most active volcanoes, erupting explosively approximately once per year. This volcano has become well known for its 1956 paroxysmal, directed-blast type eruption, similar in eruptive character to the subsequent 1980 eruption of Mount St. Helens. The local and regional hazards incurred by regular explosive eruptions of Bezymianny over the past 50 years render it an ideal research target to further understanding of eruptive cycles at explosive volcanoes that have undergone, or may be prone to, directed-blast type eruptions; this is the ultimate goal of a five-year, multi-disciplinary NSF sponsored Partnership In Research and Education (PIRE) project. One aspect of this PIRE research aims to employ gas sampling methods to constrain the composition and mass flux of the volcanic gas emissions from Bezymianny volcano during a three-year period from 2007 to 2010 in an effort to elucidate subvolcanic processes that may influence eruptive activity. The composition of volcanic gases depends on several subsurface factors, including: (1) magma composition, (2) magma solubility, (3) pressure, temperature, and redox conditions at depth, and (4) the presence of a shallow water system. Therefore the surface composition of volcanic gases can provide insight into the subsurface environment. Multiple, repeated, direct and remote, gas samples were collected at Bezymianny volcano over the sample period to evaluate how changes in volcanic gas composition and mass flux relate to changes in volcanic activity. During this time period, Bezymianny erupted explosively on five occasions: May 2007, October/November 2007, August 2008, December 2009, and May/June 2010. The specific questions we aim to address for each year of the sample period include: (1) is there a new or rising magma source? (2) is there a hydrothermal/meteoric water system present at depth? (3) what is the approximate volume of degassed magma? and (4) what is the approximate depth to magma storage? Preliminary findings from this study are presented herein.