Skip to main content
U.S. flag

An official website of the United States government

Seismicity and deformation induced by magma accumulation at three basaltic volcanoes

December 18, 2008

We analyzed the evolution of volcano‐tectonic (VT) seismicity and deformation at three basaltic volcanoes (Kilauea, Mauna Loa, Piton de la Fournaise) during phases of magma accumulation. We observed that the VT earthquake activity displays an accelerating evolution at the three studied volcanoes during the time of magma accumulation. At the same times, deformation rates recorded at the summit of Kilauea and Mauna Loa volcanoes were not accelerating but rather tend to decay. To interpret these observations, we propose a physical model describing the evolution of pressure produced by the accumulation of magma into a reservoir. This variation of pressure is then used to force a simple model of damage, where damage episodes are equivalent to earthquakes. This model leads to an exponential increase of the VT activity and to an exponential decay of the deformation rate during accumulation phases. Seismicity and deformation data are well fitted by such an exponential model. The time constant, deduced from the exponential increase of the seismicity, is in agreement with the time constant predicted by the model of magma accumulation. This VT activity can thus be a direct indication of the accumulation of magma at depth, and therefore can be seen as a long‐term precursory phenomenon, at least for the three studied basaltic volcanoes. Unfortunately, it does not allow the prediction of the onset of future eruptions, as no diverging point (i.e., critical time) is present in the model.

Citation Information

Publication Year 2008
Title Seismicity and deformation induced by magma accumulation at three basaltic volcanoes
DOI 10.1029/2008JB005937
Authors O. Lengline, David Marsan, J.-L. Got, Virginie Pinel, Valerie Ferrazzini, Paul G. Okubo
Publication Type Article
Publication Subtype Journal Article
Series Title Journal of Geophysical Research B: Solid Earth
Index ID 70198276
Record Source USGS Publications Warehouse
USGS Organization Volcano Hazards Program; Volcano Science Center

Related Content