Computer models based on the
Giant Impact Hypothesis show that the core of
Theia [which is the name for the mars-sized body which collided with the early Earth] merged with the Earth's core. So the idea of the two
cores coming together is pretty old (since the 40's according to wiki).
I guess the new idea is not that the core sank and combined with Earths' but, as the linked news article says,
"... the two may still remain,
either separate or as conjoined twins, locked in a tight orbit." Further suggesting this had a hand in starting (and/or continuing to affect)
Plate Techtonics.
The article calls this a "new theory" but, I don't see where they [Cetin & Ozkirim] are publishing anything on this. They are quoted in the
article as saying,
"We have no solid evidence yet, and we're not saying 100 percent that it still exists..." if there's no solid evidence
then there certainly is no Theory yet. At the end they quote a release from the American Geophysical Union which stated:
"In terms of its volume, and even its mass, the Earth's inner core is quite small relative to the whole planet, about 1 percent," Paul
Richards of Columbia University said. "I seriously doubt that inner core dynamics could play a significant role in moving the tectonic
plates."
Please visit the link provided for the complete story.
Cetin's page is:
Haluk Cetin, Ph.D., Associate Professor of Geosciences
(Murray State University)
I can't find one for Ozkirim but did find an abstract for their paper on this (they appear to have withdrawn it?)
here:
A Hypothesis Explaining The Dynamics Of Plate Tectonics
Since the introduction of the plate tectonics theory, one of the unsolved fundamental problems has been the understanding of how and when plate
tectonics began, as well as initial dynamics of plate tectonics although several mechanisms have been suggested (i.e. the hypothesis that
asthenospheric convections drive plates, which is not supported by modern geodynamic theories). The kinematics behind the subduction zones and sea-
floor spreading have been well understood and well described by the theory of plate tectonics. However, there is no consensus on the main driving
mechanism for the plate tectonics and how it began. We are proposing a hypothesis that attempts to explain several fundamental questions: (1) Why is
the planet Earth unique among the silicate planets of the solar system in terms of plate tectonics?; (2) How did plate tectonics start?; (3) What did
drive the lithospheric plates in the first place?; (4) Why do mantle plumes form? What kinds of forces are responsible for the plumes?; (5) Why is the
outer core fluid?; (6) Why do "ultra-low seismic velocity zones" exist at the base of the mantle?; and (7) Why does the magnetic field of Earth
change? The other explanations and examples to be presented include three-dimensional animations of the Paleoproterozoic and Neoproterozoic Earth, and
the kinematics and dynamics of the tectonic plates such as the Atlantic and Pacific plates.
I imagine if these guys have something they will publish and we will certainly hear more about it then.
[edit on Wed Jan 7 2009 by Rren]
