| アブストラクト |
Mantle convection and tidal dissipation are two important processes in terrestrial planet that control their evolution. In both of them rheological properties of planets play an important role. Among the various factors, water (hydrogen), pressure and temperature (and time-scale) have important influence on the rheological properties. The rheological properties of materials composing the mantle of terrestrial planets (i.e., minerals) can change by many orders of magnitude by the change of these parameters. Consequently, (1) understanding of dependence of rheological properties on these factors, and (2) inferring the distribution of water content, pressure and temperature in planetary interiors are critical to the understanding of dynamics and evolution of terrestrial planets. The first is a materials science issue, and the second is a planetary physics issue. Among other factors, the water content in a terrestrial planet is important in relation to the “habitability” issue and I will provide discussions on water distribution using Earth and the Moon (and Mars) as an example. A particularly interesting case is water in the Moon. I will provide evidence for a substantial amount of water in the deep mantle of the Moon based on “geo”physical observations, and discuss a plausible model to explain the relatively large water content of the Moon in the context of the giant impact model of the Moon formation.
The plan of my lectures is as follows:
Part I: Introduction
Mantle convection and plate tectonics
Tidal dissipation: orbital and thermal evolution
Part II: Some mineral physics bases Solubility of water (hydrogen) in liquids and solids Three states of matter: Importance of pressure on the condensation sequence Sensitivity of physical properties on water content
Seismological properties Electrical conductivity Rheological properties
ABC of rheological properties of planetary materials: seismic Q, tidal Q, long-term deformation
Influence of pressure on rheological properties Theoretical models
Experimental studies
Part III: Some planetary science applications
Plate tectonics on terrestrial planets
Tidal dissipation, tidal heating and orbital evolution Water in terrestrial planets
Water distribution in Earth
Water in the Moon
Giant impact and water in the Moon |
