Santa Fe Impact Structure
|"The Santa Fe impact structure is an eroded remnant of
a bolide impact crater in the Sangre de Cristo Mountains northeast of Santa
Fe, New Mexico. The discovery was made in 2005 by a geologist who noticed
shatter cones in the rocks in a decades-old road
cut on New Mexico
State Highway 475 between Santa Fe and Hyde Memorial State Park.
Shatter cones are a definitive indicator that the rocks had been
exposed to a shock of pressures only possible in a meteor impact or a
nuclear explosion. It is called an "impact structure" and not a
crater because it is so deeply eroded. Current estimates place
of the impact between 1.4 and 1.6 billion years. Only the crater's
basement rocks remain on the surface in the mountains today. The
estimated diameter of the structure is currently a subject of study,
but may be 10 times larger than the one that created Meteor Crater in
Arizona. The shatter cones occur for about 1 mile (1.6km)
highway, which is interpreted to coincide with a central area within a
crater of greater diameter. " From wikipedia
it turned out I was going to Santa Fe (and other places) over the
winter break, I figured, what better time to look for shatter cones
when they are likely buried beneath the snow!!!
Part 1 - How do you get from downtown to Highway 475?
After that, where???
going out the Hyde Park Road / Highway 475 - Trees, roadcuts, hiking
trails.... when you get to the visitor center or ski rental shop,
you've gone too far! turn around and go back towards Santa Fe - Pull
off at the pull-out on the left side where the nice exposure is...
Carefully cross the road... The closer you get, the more you
Here's our site of interest -
And the following is what is interesting about it:
Earth Impact Database Page
It doesn't say much - an estimated diameter of 6-13 km, and
an age <1200 Million years ago.
Fackelman, S.P.; T. H. McElvain, J. R. Morrow, and C. Koeberl (2007). "Shatter
Cone Exposures Indicate a New Bolide Impact Structure near Santa Fe,
New Mexico". Lunar and Planetary Science XXXVIII. Lunar and
Tegtmeier, E. L.; H. E. Newsom, W. E. Elston, and T. H. McElvain
and geological setting of the Santa Fe, New Mexico USA impact structure".
Large Meteorite Impacts and Planetary Evolution IV. Lunar and Planetary
Map images courtesy Google, all other images Copyright Ted Brattstrom 2011, 2012