University College London の Nicolas Brantut 博士の特別セミナーを下記の様に開催します。
岩石力学実験で見られる地震波速度の変化に関して、最新の結果を紹介して頂けます。お時間がおありの方は、是非お越しください。

日時：11月10日（木）　うなぎセミナーの後小休憩を挟みまして、1時間ほど
場所：防災研究所 地震予知研究センター 本館セミナー室（E-232D）
（地図の情報は末尾に）

タイトル：Recovery of seismic wave speeds after deformation: A rock physics approach
講演者：Nicolas Brantut (University College London)

アブストラクト：
In the upper crust, rocks deform by fracturing and faulting. Fractures and
microfractures have a huge impact on the physical properties of rocks, and
especially their seismic wave speeds. It is well established from
seismological evidences that important changes in seismic wave speeds occur
around fault zones in the periods following earthquakes: seismic wave
speeds tend to suddenly decrease during the earthquake, but tend to recover
significantly in the following days and months after rupture. Such trends
are key to understand how rocks recover after deformation and the state of
stress in around faults during the interseismic period. In this
presentation, I will show how laboratory rock physics experiments can
contribute to improve our understanding of why seismic wave speeds recover
after deformation, and what it tells about the stress state in the crust
following earthquakes. The essential result from my laboratory experiments
is that seismic wave speeds can recover very significantly (up to 10%) and
rapidly (over a few days) due to time-dependent microcrack closure, even
when the macroscopic stress state is maintained constant. This effect is
due to internal stress relaxation.

会場は、以下の地図の27番のE棟の2階です。
http://www.kyoto-u.ac.jp/ja/access/campus/map6r_uji.html