Upheaval Dome in Utah's Canyonlands National Park.
Upheaval Dome has long been strongly suspected to be a massive, eroded impact crater, but the LPOD highlights a study that finally puts this (non-)controversy to rest, Elmar Buchner and Thomas Kenkmann's Upheaval Dome, Utah, USA: Impact origin confirmed, documenting shocked quartz grains in the Kayenta sandstone of Upheaval's outer ring.
It's about time -- it's been pretty clear for many years that this structure was an impact formation, not a collapsed salt dome (the relative lack of salt in the core might have been a clue) but the park service doesn't seem to have gotten the message, giving equal weight to the salt-dome theory in all its Canyonlands literature and signs. Perhaps the Buchner and Kenkmann paper will finally convince them.
Reading about this gave me the push I needed to update my own
Upheaval Dome page,
adding links to the latest research and to the excellent
Dome Bibliography Kurt has put together.
My page also badly needed a bigger view of the crater itself, so
I stitched together a quick
of the view from the rim
that I'd shot on a trip several years ago but never assembled.
[ 13:15 Nov 29, 2008 More science/geology | permalink to this entry | ]