Geologist to Lead Tour of Meteorite Impact Evidence Site
Mark Jirsa, University of MN Geologist, will be leading an
interpretive walk to two Sudbury meteorite impact evidence sites on
Monday, September 21. Meet at the gravel pit on the Gunflint Narrows
Road (formerly Warren's Road) at 4:15 PM. (We will car-pool, if
necessary, to the parking area, then walk to the sites off the road.)
Mark will give a presentation later that day at 6:30 PM, at Gunflint
Lodge's conference center.
These sites are of great significance in the world of geology. The sites are
quickly becoming grown over, post-fire, so now is the time to view
and learn about this.
>From the University of MN Geology Department web site:
"In 2007, a layer of rock was discovered in Minnesota that is
thought to have formed during the Sudbury meteorite impact event.
The layer is exposed near GUNFLINT LAKE, nearly 500 miles west
of the impact site at Sudbury. It is sandwiched between
the Gunflint Iron Formation below, and slate of the Rove Formation
above. Both of these formations were deposited as muddy,
oceanic sediments. Nearly a billion years later, these rocks were
intruded by magma (Logan Intrusion) as part of a major continental
rifting event."
For more information go to:
http://talc.geo.umn.edu/mgs/meteoriteimpact.pdf (a fairly large pdf
file, so allow a bit of time for it to load)
Mark has updates of findings which have been made since the initial
discovery in 2007.