In reply to David Jonsson's message of Sun, 21 Jun 2009 11:33:08 +0200: Hi, [snip] >Measuring an adiabatic gradient is not easy and doing it on location below >the crust seems impossible.
Temperatures at various depths in oil wells? >Corect, I also did that initially, and that is the method used for gases >where the constituent moleculeas mostly are in free fall. In solid and >liquid matter this is no longer the case where molecules and atomes are >tightly bound to each other. But exactly how tightly bound are they? I >suggest someone with a centrifuge to make an experiment. Desktop centrifuges >can now produce one million g. Consider that initially the Earth was formed from matter falling inward. What form it had is irrelevant. All that matters is how much of that energy has been able to escape since formation. > >Maybe solid state physics can determine how tightly bond atoms are in a >crystal? Just look at the melting and boiling points of the substance. That will tell you how much thermal energy is needed to pull it apart. e.g. the phase change energy of melting salts is proportional to the melting point. This makes sense, because a higher melting point implies a stronger chemical bond, which in turn means that more energy needs to be added to break it. At the atomic level, the inter atomic distances for most crystals are usually on the order of 2-3 Angstrom. Since energy is force x distance, and the distances are mostly similar, the bond energy correlates with bond strength (force). Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/Project.html
