Ground deformation associated with volcanic tremor at Izu-Oshima volcano

Journal Article · Fri Mar 01 04:00:00 EST 1991 · Geophysical Research Letters (American Geophysical Union); (United States)

DOI:https://doi.org/10.1029/91GL00462· OSTI ID:5512024

Oikawa, Jun; Ida, Yoshiaki; Yamaoka, Koshun; Watanabe, Hidefumi ^[1]; Sato, Kaoru ^[2]; Fukuyama, Eiichi

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1. Univ. of Tokyo (Japan)
2. Japan Meteorological Agency, Tokyo (Japan)

Izu-Oshima volcano had summit and fissure eruptions in November, 1986 after 12 years of dormancy, and three small eruptions followed these events within one year. Episodic and continuous volcanic tremors were observed for the period containing these eruptions. It is a remarkable discovery that the episodic volcanic tremor was accompanied by a small but sharp ground deformation, the polarity of which was variable. The distribution of tilt vectors reveals that the source of ground deformation was always located beneath the northwestern flank of the volcano, where a magma reservoir was predicted by other studies. On the other hand, the seismologically detected tremor source was determined to be at a shallow depth below the central pit crater, a few kilometers away from the predicted magma reservoir. It is thus inferred that the tremor source near the crater generated pressure increases or decreases that were simultaneously transmitted through the vent to the magma reservoir and lead to its expansion or contraction.

• OSTI ID: 5512024
• Journal Information: Geophysical Research Letters (American Geophysical Union); (United States), Journal Name: Geophysical Research Letters (American Geophysical Union); (United States) Vol. 18:3; ISSN GPRLA; ISSN 0094-8276
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
580000* -- Geosciences
ASIA
DATA ANALYSIS
DEFORMATION
DEPTH
DETECTION
DEVELOPED COUNTRIES
DIMENSIONS
DISTRIBUTION
EARTHQUAKES
GEOLOGIC STRATA
GEOLOGIC STRUCTURES
GEOTHERMAL SYSTEMS
JAPAN
MAGMA SYSTEMS
RESERVOIR PRESSURE
SEISMIC EVENTS
SEISMIC SOURCES
VOLCANOES