|
|||||
|
|
Groundwater microtemperature in earthquake regions |
|
| Authors: | Hideki Shimamura Morio Ino Hisayoshi Hikawa Takaya Iwasaki |
| Institution: | (1) Laboratory for Ocean Bottom Seismology, Geophysical Institute, Hokkaido University, 060 Sapporo, Japan;(2) Earthquake Preparedness Division, Shizuoka Prefectural Government, 420 Shizuoka, Japan;(3) Earthquake Prediction Information Division, Japan Meteorological Agency, 100 Tokyo, Japan;(4) Present address: Sapporo District Meteorological Observatory, Japan Meteorological Agency, 060 Sapporo, Japan |
| Abstract: | Microtemperature measurements of groundwater with a relative precision better than 1/1000°C have been made in several seismically active areas in Japan. The measured temperatures show clear coseismic signals as well as a correlation with atmospheric pressure. Simultaneous observations at various depths have shown that these temperature changes were not induced by simple groundwater level changes. Also, distinctive signals occurred before several earthquakes and seem to be caused by a different mechanism than the coseismic signals. The microtemperature at some observation sites shows excellent correlation with records of nearby sensitive borehole strainmeters. Simultaneous recording of microtemperature and strain has been initiated in some boreholes. |
| Keywords: | Groundwater temperature Crustal strain Coseismic signal Earthquake precursor Atmospheric pressure |
| 本文献已被 SpringerLink 等数据库收录！ | |