Water-Level Changes in the Wells of Kamchatka at the Time of the Mw 7.6, April 20, 2006 Olyutorskii Earthquake

• Published in: Journal of Volcanology and Seismology
• Main Authors: Kopylova G.N., Smolina N.N.
• Format: Text
• Language: Russian; English
• Published: 2010
• Subjects: 37.31.19 Сейсмология; 38.61.15 Динамика и режим подземных вод; Kamchatka; Koryak
• Online Access: http://repo.kscnet.ru/2758/; http://repo.kscnet.ru/2758/7/ViS_Kop_Smol_10_3_angl.pdf

The seismic waves excited by the Mw 7.6 Olyutorskii earthquake that occurred on April 20, 2006 in the Koryak Upland gave rise to water-level changes in five wells situated in continental areas of Kamchatka at hypocentral distances of 750–1150 km. We describe the effects due to seismic waves, as well as the water-level anomalies for February–April 2006 before the earthquake. We used an original technique for the processing of water-level records based on the study of barometric and tidal water-level responses in order to estimate the volume strain in water-saturated rocks during synchronous level variations at two wells. We discuss possible mechanisms for producing anomalous water-level changes due to elastic deformation of monitored groundwater reservoirs and to crack dilatancy in the water-saturated rocks.