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Earth and Planetary Physics Group

The Earth and Planetary Physics Group conducts research on the formation of the solar system (the growth process from dust to
planets), evolution of planets, co-evolution of earth and life, physical processes of climate change, and geophysical phenomena
occurring in the Earth and planets (earth quakes, volcanism, convection, etc.). We also study related fundamental physical problems
essential for understanding the formation and the evolution of the Earth and planets, such as collisional disruption, rheology,
physical properties of granular matter.

Research Subjects

Volcanic eruptions and earthquakes

Studies on the basic physical processes of volcanic eruptions and earthquakes and the improvement of volcano and earthquake monitoring

Source quantification of volcano-seismic signals and eruption mechanisms

We observe and analyze various seismic signals at active volcanoes and examine their relationships with volcanic eruptions.

Source processes of large earthquakes in plate subduction zones

We deploy earthquake monitoring networks in the Asia-Pacific plate subduction zones and study the source processes of large earthquakes in these areas.

Improvement of volcano and earthquake monitoring techniques

We study volcano and earthquake monitoring techniques using the latest seismological knowledge. Our original monitoring techniques are used in Philippines, Indonesia, Ecuador, and other countries.

Soft matter geophysics

The Earth and other planets consist of soft materials such as atmosphere, water, sand, mantle, etc. Understanding the behaviors of these materials is an essential part of understanding the related geophysical phenomena.
With this goal in mind, we conduct experimental studies of the fundamental physical properties of such soft materials. In particular we are interested in granular matter, which shows many counterintuitive and fascinating phenomena.
Our group stirves to develop new types of experiments that help further our understanding both of the fundamental physical processes and the related geophysical phenonemena. For instance, the impact cratering experiments with granular targets have been investigated using both solid and liquid-drop impactors.
The rheology of granular materials and cratering morphology are important aspects of many planetary and geophysical problems. Our research also incorporates a range of other geophysically relevant experiments and measurement techniques.

Formation of planetary system, Coevolution of earth and life, and Lunar and planetary exploration 

Prediction of long-term climate change from simple models

Is the Earth warming? Climate change is predicted by general circulation models (GCMs). These models are based on the phenomenologically-derived response of the present climate system, which may not be valid for a warmer future.
So, we are developing simple models based only on sound elemental processes to simulate the nature of atmosphere-land-ocean-life interactions. The results can be incorporated in GCMs for more accurate future predictions from
numerical studies.

Planetary formation

What was the formation mechanism of Earth? Where was the birthplace of organic materials for life? About one thousand extrasolar planets have been found since 1995. Is our solar system special, or common in Universe? We try to solve these questions through analytic and numerical studies.

Lunar and planetary exploration

We are studying the morphology and the interior of the planets and moons using geophysical and geological data obtained by lunar and planetary missions. Our group is also active in research and development of lunar and planetary exploration as science members of SELENE and Hayabusa-2 projects.

Details of this group

  • Earth Environmental Systems Group
  • Geology and Geobiology Group
  • Geochemistry & Cosmochemistry Group
  • Earth and Planetary Physics Group
  • Earth and Planetary Dynamics Group
  • Chronology and Natural History Group
  • Ecology
  • Hydrospheric-Atmospheric Science

For undergraduates
who hope to join our



Graduate School of Environmental Studies

Graduate School of Science ⁄ School of Science

Hydrospheric Atmospheric Science