Seminars Archive
Probing the Earth`s core with quantum mechanics
Abstract
Wednesday, January 26, 2005, 14:00
Seminar Room, ground floor, Building "T"
Sincrotrone Trieste, Basovizza
Probing the Earth`s core with quantum mechanics
Dario Alfe`
(Dept. of Earth Sciences, and Dept. of Physics and Astronomy
University College London)
Abstract
The heat coming from the Earth`s core is one of the most important
sources of energy which drive all the dynamics processes inside our planet,
and ultimately also surface processes like volcanism, plate tectonics and
earthquakes. The main constituent of the Earth`s core is iron, therefore
its elastic and thermodynamic properties at high pressure and high temperature
are central in our understanding of the properties of the core. We also
know that the core must contain some light impurities like S, Si, O, etc.,
as iron is 6-10 % too dense. As the (solid) inner core freezes, these light
impurities are released in the (liquid) outer core, and rise to the surface
of the core. In doing so, they stir the liquid into convective motions
which are responsible for the generation of the Earth`s magnetic field.
Two big questions in Earth`s sciences are therefore what is the temperature
and the composition of the Earth`s core. In this talk I will focus on high
pressure high temperature properties of iron and iron alloys calculated
using first principles thermodynamics. In particular, I will present the
melting curve of iron and constraints on the possible composition of the
the Earth`s core.