On May 14, 2:43*am, Dave Typinski wrote:


determined by core samples of the Earth's crust, mantle, and core? I
didn't think we had the latter two yet.

Inferred from seismic analyses, aren't they? *Whether they're known or
not, I don't understand why this would matter. *The distribution of
mass within the Earth will make a difference to the gravitational
potential field interior to Earth's surface. *External to the surface,
it's a point mass with corrections for centripetal acceleration and
surface altiutude deviation from an ideal ellipsoid.

Dave

Point mass indeed !,dynamicists have been working with spherical
deviation and fluid dynamics in stars for years but can't make the
leap to applying it to the Earth's viscous interior even though
surface features such as the MAR contain signatures of rotational
dynamics and specifically differential rotation.

Oh ,that's right,you have trouble understanding my sentences so I am
going to make a special effort to translate it for you in the most
simple way - the Earth is round and rotating and because the Earth is
mainly a viscous rotating composition,it will not be pefectly round.

I would not want to overload your brain with the next step which is
applying the same dynamic to crustal evolution and motion which
replaces stationary Earth 'convection cells' (which require no
reference to rotation or rotational orientation).