Welcome to the blog for the Oberlin College Geomorphology Research Group. We are a diverse team of students working with Amanda Henck Schmidt on geomorphology questions. This blog is an archive of our thoughts about our research, field work travel notes, and student research projects. Amanda's home page is here.

Tuesday, January 31, 2017

Winter Term 2017: Dynamic Duo Wrapup

Hi folks! Monica and Simon here.

Simon here:

I had a great Winter Term. The was my first (and only) on-campus Winter Term, and I have to report that it was fabulous. I really appreciate Monica taking the time to show me around the lab and for showing me how to do what we do, and answering a multitude of questions. 

This last week has involved a lot of cleaning the lab in preparation for the start of the spring semester (See CLEAN GeoChem Lab picture to the left). I emptied a lot of sample containers by placing the samples in bags, so we'll have plenty of containers to re-use. I also learned how to refill the germanium detector's liquid nitrogen tank. Today, we all cleaned the Geochemistry lab so that it will be nice and neat for the beginning of the next semester. Next semester, I won't be doing much leaching like I did during Winter Term. Instead, I'll be doing GIS (Geographic Information Systems) stuff. I took Amanda's GIS class semester, and I'm looking forward to keeping up/improving my GIS skills since it'll be important for getting jobs after I graduate in May. Here's to a great final semester!

Monica here:

These are some of the crates we have filled with samples from China.
I spent my second half of Winter Term working on cataloging all of the lab's samples and storing them into Severance, while of course still collaborating with Simon on running samples. 

To catalog the samples, I often had to take them from metal trunks that were used to transport them from China or other Colleges and Universities and enter each sample into spreadsheets that Megan had worked on a little bit this past summer. While I am certainly not finished yet, I do feel accomplished in adding over 800 samples into our records so far. It has been exciting to see/interact with so many new types of samples. I've definitely really expanded my view of all the projects that our lab works on, and the different ways we can work with a sample to get different data sets.
Overall we both had a blast, and as usual Harbin was there to see all the misadventures, small discoveries, and mostly hours of hard work. Yet another successful Winter Term in the books, time to transition into classes and keep at the pursuit of Geomorphological knowledge!

Last day lab selfie! (We couldn't resist)

Friday, January 20, 2017

Hi Geo peeps/fans! Simon here.

          I just started working in the lab over this Winter Term, and I'll be continuing into the next semester. I'm a senior Geology and Environmental Studies double-major from Baltimore, MD, and I'm thrilled to be doing research in this lab.

          I've been learning the nuts and bolts of working in the lab: what we do, and how to do it. I've been learning how to leach samples, centrifuge them, dry them down, and then run them in the Germanium detector. There's only Monica and myself working in the lab right now, so there is plenty to do!
Sieving a soil sample
Pouring a dried sample into a leaching bottle
Pouring Hydrochloric Acid into a sample to leach it
Once the leachate is removed from the solid residue through centrifuging,
I add Sodium Hydroxide to neutralize it
          Amanda gave me a project to determine how much water the samples absorb as they sit in the sample containers after being dried down. The assumption is that they do absorb some water because they have a high salt content (from the HCl reacting with the NaOH) and salts tend to absorb water. Gaining a better understanding of the water content in each sample will allow for a more accurate analysis of the composition of each sample.

          To test how much water is absorbed, I took some prepared samples and dried them down by placing them on the hot plate for two days. Of the nine samples, I chose three each of various masses to be left open, closed, or closed and sealed with electrical tape. I just started the experiment this morning, but I'm already seeing results, particularly from the samples left open to the air.

Water absorption experiment
          This Winter Term is going well and I'm looking forward to a great semester working in the Geomorphology Lab!

Until next time,

Selfie with Harbin (the germanium detector)

Tuesday, January 17, 2017

We're not in (Ar)Kansas Anymore!

Hello everybody,

For the first part of my winter term project this year I was able to help take samples at a few sites within Northern Arkansas. The project began as way for Dr. Amanda Keen-Zebert and Dr. Stephanie Shepherd to return to home and do some investigating in their backyard and developed into a hugely collaborative endeavor. Professors, grad students and undergrads (hey, thats me!) from different institutions across the US have expressed interest and offered to help in whatever way possible. The goals of this trip in particular were to obtain OSL samples from several terraces within some federally recognized park sites and also to perform Terrestrial Lidar Scanning (TLS) on bluffs that were of interest.

While we flew in on Wednesday night, we didn't make it back to the cabin until around 1AM, so there wasn't anytime for introductions or anything like that. So the next morning after breakfast we had a more formal sit down chat where everyone had the chance to introduce themselves and learn about the project. After that was done we loaded up the cars with supplies and headed out to the first site, Steel Creek. This location was only a 15-20 minute drive from our cabin, which was really nice as the day became brutally cold very quickly. Dr. Keen-Zebert had intended to spend the day both digging and scanning but as it was such a easily accessible and popular location for campers, we didn't know if we had permission to dig. So onto scanning then. The scanner is a machine that looks like a larger than usual lunch box with a rotating camera embedded on the top, which has to be mounted and leveled on a tripod. This machine also costs upwards of $40,000, so you want to make sure that tripod is firmly planted into the ground. Scanning went well enough for most of the morning, but as snow and the temperature started falling, the batteries started failing. After running back and forth between charging stations and the scanner for nearly an hour we had to call it quits.

Here I was able to level the machine with the assistance of Malcolm Willamson (Red Hat) and Mike, an Auburn University graduate student

Friday and Saturday the weather was still cold but we were able to keep warm by digging! After making the two hour journey to the Margret White site, Dr. Shepherd and Keen-Zebert showed us the locations for the two trenches. There isn't a whole lot to say about these days, they just included a lot of physical labor. On Saturday, before we started digging we did get to do a small field trip and explore the surrounding region, learning about the different rock types that are present within the local environment. Not surprisingly in a region shaped by fluvial activity, there was a lot of sandstone. 
The open field before we started trenching

On Sunday we had a little bit of a repreive after digging for two days and were able to learn about and see how Optically Stimulated Luminescence (OSL) sampling works. Its a process which takes advantage of impurities in the structures of quartz rich samples. Specifically Amanda was looking for a sample which doesn't have a uniform composition and holes were allowed to develop at the molecular level. These holes allow electrons to get stored when the sample is not in the presence of light. The process is somewhat analogous to charging a battery. 
The team finding a location to sample from on a bank that is somewhat shielded from direct sunlight.
Monday we went back to the Margret-White trenching site, this time accompanied by Amanda and Stephanie's professor from grad school who specialized in soils. The weather had also made a complete 180 and turned out to be around 60-70 degrees.

Sam, a Grad Student from Auburn University, explaining soil horizons to Hannah, Kathleen and I

Tuesday we had the fun job of refilling and erasing all of our hardwork  the trenches.

Its totally not a grave, I swear

We then closed off the week by going back to the Steel creek site and helping finish off the TLS work that we could not do because of the weather earlier. The process involved setting up the scanner with the right parameters and letting it do its thing for anywhere from 30-40minutes. In that time you could do anything you want, Malcolm and I skipped a lot of rocks, but you just had to make sure to not be in the field of view while the scanner was going. 

Malcolm being a brave, brave soul and carrying the scanner into the water and across very slippery rocks

Well, that was pretty much the extent of the trip, I had an absolute blast and if this at all interested you, there is a facebook page, Buffalo River Geoscience, set up which posts periodic updates about the project. 

Until next time,

Friday, January 13, 2017

As our work intensifies, the winter does not

Hello Geo lovers! Monica here!

It's officially halfway through winter term and I can say for a fact that I do not believe snow on the ground has lasted without melting for more than a couple days since I arrived. It (almost) makes me nostalgic for the frigid and snowy Wisconsin winter days I chose to forgo to spend Winter Term here in Oberlin!

While the winter weather may disappoint, work in the lab is more exciting than ever. I spend my first week focusing on creating graphs and playing around with some variables to further refine the leaching process and better understand how specific we need to be to still be accurate with the programs/technology we use in the lab.

I finally (!!!) finished my project where I was testing out different ratios for the acid:sediment relationship during the leaching process. Even though the curve I created wasn't as smooth as we would have liked it to be (or frankly, smooth at all), it still showed that the original ratio we used is effective and the best choice. Which, perhaps, might be actually the best result. It's always reassuring to get confirmation you were doing something the best way all along.

Amanda also gave me a little side project of figuring out how light the elements we want to detect (to get the composition of a sediment) need to be to still get accurate activity levels. This is essentially because elements get harder and harder to detect the lighter (smaller on the periodic table) they get. I got to use my old friend ANGLE to run a bunch of calculations fiddling with different elements and it made me nostalgic for the days of STRONG this summer, although I am grateful for how time has dramatically improved my abilities to navigate excel.

I am also tracking down, compiling and preparing all of the data for the samples we need to our next paper on the leaching process. Unfortunately Amanda's multitude of projects create a lot to search through when a sample decides to go rogue, but it's good preparation for part of my work for the second half of winter term, which is to organize and catalog all the lab samples. Luckily I have the help of Simon, who just started in the lab and will post next week. I've also been busy teaching him the ways of the Dirt lab (aka leaching) and generating camaraderie between the current dirt lab members and alums (s/o to Joe).

Regardless, between writing/editing our paper, generating graphs, running samples, leaching, and organizing samples, things are busy and happy in the lab. I guess I'll use the time I wanted to spend sledding and skating leaching more samples and wishing for colder days.