Catching up after Italy

Well, I didn't get nearly as much blogging done in Italy as I might have hoped. Two big reasons - one is that we spent most of our waking hours as you see on the left, up to our knees in Torrente Stirone.



The other, as you see in the second picture, is that our apartment was a bit remote and had no Internet access of any sort.

So now, I'm back and I'm finally caught up with what was waiting on my desk, so I can get a few updates posted on my time in Italy.

We had a great time. The grad student, whose project this is, Kellen, three faculty working with him, and I all had a chance to work together and we got a lot done. The primary work involved measuring the stratigraphic section and sampling for magnetic intensity and for magnetic reversals. For magnetic intensity, we took bulk samples of the sediment every 0.75 meters or 1 meter of section. Because the rocks were tilted, this corresponded to about 2 to 2.5 meters along the river bank. We needed a way to mark the sample sites and the normal method of using a dot of spray paint was not going to work on these soft and wet muds.

On our very first day, inspiration hit when we stopped for gelato on our way home. The little plastic gelato spoons were brightly colored, had a flat area where we could write a number, and a relatively stiff stem that could be pushed into the mud. Our one Italian speaker asked the proprietor if we could buy some and he responded "This is not a spoon store." We persevered and the next morning, we were able to buy a big bag of gelato spoons from the owner. Here is one of those spoons marking a sample site.



After all the samples had been collected, we removed the spoons. Here's is the first day's take.


When I left Italy, we had collected over 500 of these samples. They will be analyzed for their magnetite content to test the hypothesis that there will be a periodicity to the magnetic intensity that matches the 100,000 year and 400,000 years cycles of eccentricity in Earth's orbit around the sun. These cycles are paralleled by climate cycles, making the magnetic intensity measurements a proxy for climate and allowing the project to evaluate possible links between climate cyclicity and patterns in deformation, if there are any. As this data comes in, I will be working to figure out how students can engage with this data set to understand more about basic concepts in earth science, but first we wait and hope that all those boxes yield something useful.

Coming up next: 6 million years of mountain building and climate, recorded in sediments.

Little Boxes on the Hillside... (or at least on the riverbank

The free Internet at the local library won't talk to Blogger, so it's time for a cell phone update. We have been busy collecting samples of mud for the magnetic study. Every two meters along the bank, we stuff a 2 cm plastic cube with sediment, mostly mud. The boxes have been pre-weighed and numbered, so we have to keep track of which is which and where they get filled. Today, we collected oriented samples to look for magnetic reversals. In order to preserve the orientation while getting it into the box, we had to carve little pedestals of mud and slip the boxes over them, then measure the orientation of the box before cutting the box off of the outcrop, trimming off the excess, and putting on the lid. 9 boxes took 6 hours.

Tomorrow is a field trip then one more day in the river before heading home.

Day 3 in the field: we have measured and sampled more than 60 meters of sand and mud, sampling every .75 m. The rocks are Miocene and Pliocene and are barely lithified. They look like rocks, but you sink in to your ankles when you step in a wet spot. We've also seen a whole set of Quaternary gravel terraces, some of which are tilted by deformation.

More details on Thursday!