[meteorite-list] Classification tidbits & consequences

[Herbert Raab]

Zelimir Gabelica wrote:

> Actually, according to the official nomenclature, LL6 is not
> included in the LL3-7 mention.

The Introduction to the last (and previous) MetBull states:

> Hyphens in petrologic type assignments for chondrites (e.g.,
> "H5-6") indicate the range of types observed in breccias

So a classification of LL3-7 would mean that the the range of
types between LL3 and LL7 wss observerd. But as fas as I under-
stand, the range need not to be observed completely, so LL3-7
could also mean that LL3, LL5, LL6 and LL7 have been observed,
but not LL4, for example.

> One should then rather write "LL3/7", this meaning that all
> types from LL3 to LL7 are present.

Accoridng to the MetBull, "slashes (e.g., "H5/6") indicate
transitional assignments", and I doubt that there would be a
transitional type between LL3 and LL7. :-)

> not clear though whether this implies that LL6 is the impacted
> body or the impactor.

I think this implies that LL6 is the dominant lithology. I think
the question what was the impactor and what was the target is not
easy to answer, and it it would even ask for a definition of
"impactor" and "target". If a small meteoride collides with a large
planet (like the Earth) this is obvious, but when small meteorides
collide (which are possible of similar size) it's not that easy...

Best greetings,

  Herbert Raab