Detecting a mass change inside a volcano by cosmic-ray muon radiography (muography): First results from measurements at Asama volcano, Japan
Abstract
A visual detection and monitoring of volcanic eruptions is the most essential information. In February 2, 2009, Asama volcano, Japan erupted and a large amount of volcanic ash was ejected from the vent. We have observed the activity at Asama since October 12, 2008. For eruption monitoring we used cosmic-ray muon radiography (muography), a new volcano monitoring system recently developed by Tanaka et al. (2009). We measured a quantitative mass loss inside the crater during the eruption event although no changes were found below the crater. The measured value of 30,780 tons is consistent with a model calculation of volcanic ash flow as observed on February 2, 2009. The obtained radiographic image suggests that a “boiling liquid expanding vapor explosion” occurred and a part of an old lava mound was exploded. This picture is consistent with the analytical result of the volcanic ash ejected on February 2, 2009.
- Publication:
-
Geophysical Research Letters
- Pub Date:
- September 2009
- DOI:
- 10.1029/2009GL039448
- Bibcode:
- 2009GeoRL..3617302T
- Keywords:
-
- Volcanology: Volcano monitoring (7280);
- Volcanology: Instruments and techniques;
- Volcanology: Remote sensing of volcanoes