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Article: Detection of coseismic changes of underground water level.
- Article from:
- Journal of the American Statistical Association
- Article date:
- June 1, 1996
- Author:
CopyrightCOPYRIGHT 1996 American Statistical Association. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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1. INTRODUCTION
Various anomalous changes of underground water level accompanied by large earthquakes have been reported since ancient times (Roeloffs 1988). But it is actually quite difficult to quantitatively evaluate a preseismic effect (precursor of the earthquakes) or even a coseismic effect (changes related to or caused by earthquakes) from the observed water level data. That is because the underground water level is seriously contaminated by various aseismic effects (changes occurring without earthquakes), such as barometric pressure, earth tide, and precipitation (Bredehoeft 1967; Kearey 1993; Narasimhan, Kanehiro, and Witherspoon 1984; Roeloffs 1988; Van der ...