[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: Enstatite delivery mechanism?
bernd.pauli@lehrer1.rz.uni-karlsruhe.de (Bernd Pauli) wrote on 1998-March-13:
[...]
>KEIL KLAUS (1989) Enstatite meteorites and their parent bodies
>... suggest that
>the parent bodies of enstatite meteorites formed in the inner regions of
>the asteroidal belt and not in the immediate vicinity of the Earth-Moon
>system (e.g., Wasson and Wetherill, 1989).] ...
>
>... In either case, 26Al could not have been an effective internal heat
>source.
>If decay of short-lived radionuclides was not the heat source, then
>unipolar dynamo induction heating by a primordial T Tauri sun (e.g.,
>Sonett et al., 1968, 1970; Herbert and Sonett, 1978, 1979; Herbert et
>al., 1989) appears to me to be the only viable alternative. For this
>process to be effective, moderately high initial temperatures are
>required to provide sufficiently high electrical conductivities of
>rock-forming minerals ...
>
>Regards, Bernd
To paraphrase then:
1) oxygen isotope ratio positions them near the
earth-moon radius from the protosun, probably farther.
This is based on the distribution expected due to condensation
of the panetary nebula.
2) The temperature was quite high already in that region to allow
for a conductive material in the parent body
3) The protosun, in T-Tauri stage was spinning fast enough and
had such an intense magnetic field that metallic objects as far away as the
near asteroid belt were heated to near melting point.
Does this sum up current opinion?
This early solar system must have had some awesome lightening
phenomena - bolts may have extended through thousands of kilometers
of this semi-molten matter nearer the protosun.
Could ureilites be the fulgerites in this early solar system?
--
Jim Hurley
Arachnaut's Lair
http://www.arachnaut.org/ >
References: