地球惑星科学専攻 地球科学輻合部特別講演会

講演題名：
Accelerating creep as a precursor of stick-slip-instabilities and the problem of
prediction of "earthquakes"

講演者：
Dr. Valentin L. Popov
Berlin University of Technology, Institute of Mechanics, Germany

日時・場所:
2010年6月10日(木) 10：00～11：00
京都大学理学部1号館5階563号室

講演要旨:
Earthquakes can be considered as a result of frictional instabilities in the
fault system of tectonic plates. Similar instabilities can be easily reproduced
and investigated in detail under laboratory conditions. In the presented work a
simple tribological system with pronounced stick-slip motion has been studied
experimentally as a model of earthquake. Observation of the movement of the body
with resolution of 8 nm shows that during the entire "stick" phase, there is a
slow creeping motion which quickly accelerates near the "slip" phase. This
creeping motion is regular enough to serve as a basis of prediction of the
moment of instability. We have shown that the entire movement of the specimen
including both the accelerating creep and the rapid slip can be very good
described using the rate and state dependent friction law by Dieterich. The last
part of creeping motion immediately preceding the instability has a universal
character and allows predicting with high precision the moment of the
slip-instability. Generalizations to multi-body systems are discussed as well as
to real tectonic systems are discussed.

問い合わせ先:
堤　昭人