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Data Processing Methods for 3D Seismic Imaging of Subsurface Volcanoes: Applications to the Tarim Flood Basalt
Published on: August 7, 2017
Seismic anisotropy beneath Ruapehu volcano: a possible eruption forecasting tool
Alexander Gerst1, Martha K Savage
1Institute of Geophysics, School of Earth Sciences, Victoria University of Wellington, New Zealand. publications@planet3.de
Science (New York, N.Y.)
|November 30, 2004
Summary
Volcanic eruptions at Ruapehu Volcano significantly altered seismic anisotropy orientations. These shifts in crustal stress, linked to magmatic activity, suggest a new method for volcano monitoring and eruption forecasting.
Area of Science:
- Geophysics
- Volcanology
- Seismology
Background:
- Volcanic eruptions can induce significant changes in the subsurface stress field of a volcano.
- Seismic anisotropy, the directional dependence of seismic wave speeds, is sensitive to crustal stress.
- Ruapehu Volcano in New Zealand has a history of significant eruptions and magmatic activity.
Purpose of the Study:
- To investigate the impact of volcanic eruptions on crustal seismic anisotropy at Ruapehu Volcano.
- To assess the potential of seismic anisotropy changes as a monitoring technique for volcanic stress.
- To explore the possibility of using these changes for midterm volcanic eruption forecasting.
Main Methods:
- Seismic anisotropy was measured using seismometer deployments in 1994, 1998, and 2002.
- The fast anisotropic direction was used as an in situ measurement of crustal stress.
- Analysis focused on changes in anisotropy orientation before and after the 1995-1996 eruption.
Main Results:
- Crustal seismic anisotropy orientation changed by up to 80 degrees at least twice.
- A significant stress direction change was observed following the 1995-1996 eruption.
- Measurements in 2002 indicated a partial return to the pre-eruption stress state.
Conclusions:
- Volcanic eruptions, specifically dike-related magmatic activity, can cause substantial and rapid changes in crustal stress.
- Seismic anisotropy measurements offer a valuable tool for monitoring stress variations beneath volcanoes.
- These findings support the development of new techniques for midterm eruption forecasting.
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