Fig.1 Seismic and tilt observations at Sumeru volcano, Indonesia
Fig.1 Seismic and tilt observations at Sumeru volcano, Indonesia
Fig.2 Simulated energy field at the lapse time of 50s.
Fig.2 Simulated energy field at the lapse time of 50s.
Research Subjects

#Dynamics of various phenomena such as earthquakes and volcanic eruptions occurring in the solid Earth
#Heterogeneous structures inside the solid Earth and seismic wave propagation processes in heterogeneous media
Research Outline

The solid Earth physics laboratory aims to clarify the basic laws governing a changing solid Earth structure, fault ruptures, propagation characteristics of seismic waves, volcanic eruptions, and various solid earth phenomena by making full use of theory, observation, data analyses, numerical simulation, and other means, particularly addressing the heterogeneity and complexity of the solid Earth.

Earthquakes are considered to be brittle failures of heterogeneous materials in the Earth. The heterogeneities make the growth of the failures become so complex that seismic waves radiate in a broad period range. We study the short-period seismic wave radiation from intermediate to large earthquake in the world. We try to make use of the results for predicting strong ground motions and mitigating earthquake disasters.

Various kinds of volcanic and eruptive activities are produced through interaction between magma comprising mixed phases of gas, liquid, and solid and surrounding rock bodies. We study the dynamics of volcanic eruptions on the basis of modeling of magma ascent process and eruption dynamics as well as analyses of geophysical data obtained at active volcanoes around the world.

Seismic waves provide us with useful information related to Earth's interior structure that has been formed over a long period of time: Earth's subsurface, crust and mantle are spatio-temporally changing and are full of small-scale heterogeneities that cannot be described in terms of a classical spherical shell structure. We study these heterogeneous structures by using seismic interferometry methods and seismic scattering/attenuation modeling.

Staff members and current subjects of research (as of September 30, 2015)

Prof. Takeshi Nishimura: Source processes of volcanic earthquakes, Volcanic eruption and magma ascending processes, Heterogeneous structure or the solid earth
Assoc. Prof. Hisashi Nakahara: Generation and propagation processes of short-period seismic waves, Earthquake source processes
Asst. Prof. Tomofumi Kozono: Transition of eruption styles during volcanic eruptions, Non-linear dynamics of multi-phase conduit flow
Asst. Prof. Kentaro Emoto: Seismic wave propagation in random heterogeneous media
Home Page:
http://www.gp.tohoku.ac.jp/zisin/index_en.html