[BR-Crater] visit to Moapa NV circular feature

[Ian Kluft]

On Wed, May 28, 2008 at 12:05:36PM -0500, Scot Wilcoxon wrote:
> The pictures of the Mormon Mountains seem to show near-horizontal rock
> layers.  Would that be expected in an impact uplift?

I'd expect it could when looking at a cross-section perpendicular to a
slope.  Another is looking at near the center of an uplift, slopes should
be more gradual near the highest point.  Also, in an uplift, breccia and
melt rocks should fall on top of target rocks adding layers to any that
might already be there.

The shape of the two ranges on the topographic maps suggest that both
would be part of one uplift.  The slope of the East Mormon Mountains
up toward the Mormon Mountains agrees with that.  The gap between them
could be due to erosion or faulting.

Google says there's an unresolved geologic debate and study over the origin
of that particular area.  (We found this late last year in discussion on
the #br-crater IRC channel.)  Search for "Mormon Peak Detachment"...
   http://www.google.com/search?q=%22Mormon+Peak+Detachment%22

> Incidentally, the Mormon Mountains Wikipedia article has a picture request
> on the Talk page.

OK, done.