TY - JOUR
T1 - Gravity variation around Shinmoe-dake volcano from February 2011 through March 2012-Results of continuous absolute gravity observation and repeated hybrid gravity measurements
AU - Okubo, Shuhei
AU - Tanaka, Yoshiyuki
AU - Ueki, Sadato
AU - Oshima, Hiromitsu
AU - Maekawa, Tokumitsu
AU - Imanishi, Yuichi
N1 - Funding Information:
Acknowledgments. We express our sincere thanks to the Japan Meteorological Agency for providing us with ground tilt data at Takachihogawara. Special thanks are given to the Geospatial Information Authority of Japan, the Japan Meteorological Agency and National Research Institute for Earth Science and the Disaster Prevention for allowing us to use the displacement data derived from the GNSS. Drs. J. Oikawa, A. Watanabe and K. Aizawa are acknowledged for their technical support in acquiring the absolute gravity data. The critical comments of anonymous reviewers were helpful in improving this manuscript. This work was supported in part by Grant-in-Aid for Scientific Research (22900001 and 23244092). Some of the figures were prepared using the GMT program (Wessel and Smith, 1998).
PY - 2013
Y1 - 2013
N2 - We report here on continuous absolute gravity measurements made between February 2011 and March 2012 and repeated relative gravity measurements in the vicinity of Shinmoe-dake volcano, which commenced erupting in late January 2011. We find that 20 of 24 eruptive events are associated with precursory short-term gravity decreases occurring over 5-6 hours followed by quick recoveries lasting 1-2 hours. Also evident are significant long-term gravity changes arising principally from hydrological processes around the volcano, where annual precipitation exceeds 5, 000 mm. To isolate the gravity signal associated with volcanic processes, we compared gravity measurements made at 15 sites in March 2011 and again in March 2012. The gravity changes and crustal deformation observed during the one year period are well explained by 6 x 106 m3 inflation of a magma reservoir at a depth of 9 km and intrusion at shallower depths of a dike with dimensions of 10 km x 0.5 km x 0.5 m.
AB - We report here on continuous absolute gravity measurements made between February 2011 and March 2012 and repeated relative gravity measurements in the vicinity of Shinmoe-dake volcano, which commenced erupting in late January 2011. We find that 20 of 24 eruptive events are associated with precursory short-term gravity decreases occurring over 5-6 hours followed by quick recoveries lasting 1-2 hours. Also evident are significant long-term gravity changes arising principally from hydrological processes around the volcano, where annual precipitation exceeds 5, 000 mm. To isolate the gravity signal associated with volcanic processes, we compared gravity measurements made at 15 sites in March 2011 and again in March 2012. The gravity changes and crustal deformation observed during the one year period are well explained by 6 x 106 m3 inflation of a magma reservoir at a depth of 9 km and intrusion at shallower depths of a dike with dimensions of 10 km x 0.5 km x 0.5 m.
KW - Absolute gravity
KW - Magma transport
KW - Precursory gravity signal
KW - Shinmoe-dake volcano
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U2 - 10.5047/eps.2013.03.014
DO - 10.5047/eps.2013.03.014
M3 - Article
AN - SCOPUS:84884393222
VL - 65
SP - 563
EP - 571
JO - Earth, Planets and Space
JF - Earth, Planets and Space
SN - 1343-8832
IS - 6
ER -