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Here are some photos from my work in the Atacama. Click on an image for a larger version. Please do not use these images without citing me.
There is a lot of salt in the Atacama, mostly gypsum but also nitrate, halite, iodate, and barite. It makes digging soils pits very difficult and an electric chisel is the only way to go, unless you find some mining excavations...
An exposure from a Miocene soil showing the development of salt polygons which get coarser with depth. On hillslopes, the shrink-swell of the salt may be an important transport process.
At a sandier site, where you can see both small scale polygons at the top of the profile, and large scale wedges towards the base.
When we brush away the top few centimeters of dust, we can see the tops of the fine polygons (here at one of Brad Sutter's sites it's nicely developed).
Even without brushing off the surface, sometimes there's expression of the underlying polygons.
Here a drainage has washed and etched the surface near Antofagasta. Kuni Nishiizumi is standing in the background, probably looking for meteorites...
Closer up, you can see that each big polygon is made of a honeycomb of smaller ones.
The power of the salt is unmistakable - here's the surface expression of some salt-shattered rock.
My hillslope sites span a range of climates. This is the view from my southernmost site near La Serena. Brad Sutter was helping me with field work.
Going farther north, things dry out and the hillslopes are soil free. This is near Chanaral, just south of Pan de Azucar. The hillslopes are surrounded by a vast pediplain.
Farther north still we enter the truly hyperarid region of the Atacama Desert. This is looking back at a hillslope I studied. The bulldozer paths are left over from copper mining explorations. You can just see our tent and truck at the base of the hill.
We've also done some ash sampling. Here I'm collecting samples from the wall of an ash mine outside Antofagasta with the help of my bulldozer friend.
Brad and I were camping during the 2005 earthquake in Tocopilla. We were camped about 200 km south of the epicenter, making dinner, when we heard a rumble coming from the north. Then we started swaying. It was gentle but lasted over 2 minutes! I didn't even know you could hear earthquakes!
Here's the team from 2006: Ron Amundson (my advisor), Bill Dietrich, Sarah Reed, me, and Bob Finkel.
Equally important is our collaborator Guillermo Chong-Diaz who has helped with site locations, ideas, and logistics throughout our work there.
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