Open AccessDislocation melting of iron and the temperature of the inner core boundary, revisited
Author(s) -
Poirier J.P.,
Shankland T. J.
Publication year - 1993
Publication title -
geophysical journal international
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.302
H-Index - 168
eISSN - 1365-246X
pISSN - 0956-540X
DOI - 10.1111/j.1365-246x.1993.tb05594.x
Subject(s) - melting point , dislocation , thermodynamics , core (optical fiber) , freezing point , materials science , monte carlo method , inner core , physics , composite material , mathematics , statistics
Summary The melting point Tm of iron at conditions of the Earth's inner core boundary (ICB) has been calculated from the dislocation theory of melting in metals. These calculations take into account the effects of pressure at ICB conditions and of possible freezing point depression resulting from dilution of pure iron in the outer core. Monte Carlo calculations have been used to estimate the uncertainties introduced by uncertainty in the geophysical parameters that are used in the calculations. With this approach Tm of pure e‐Fe at a pressure of 330 GPa and without freezing point depression is 6160 ± 250 K, and 6110 K for a 1000 K freezing‐point depression, Tm of pure y‐Fe is not significantly different; these values agree well with shock‐wave determinations of Tm. The estimated temperature of the ICB is lower by the freezing point depression, perhaps by 500‐1000 K.