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.

Monday, July 25, 2016

Young Geologists' Field Day

Hello hello,

Lab work this summer has been lots of fun, it’s also been flying by! I feel like I’ve only just arrived but here it is, the last week to get some work done. Just a few days ago Monica and I had the opportunity to go and collect samples locally from the Vermillion river. While not as exciting as a trip to China, it was definitely a fun experience. Before we could go, Monica and I had to round up the supplies from the many different rooms Geology holds within Carnegie and Severance.  Those supplies included several sieves and buckets, a fair few sample bags, a large spoon to collect the sample from the river and a handful of spoons to move the sediment from the sieve into the bags (super scientific, I know!) Some people who are more critical of their terrain may look at the photos and say that we were not in a river as much as we were in a drainage ditch on the side of the road; I would say to those people, you’re right, but where’s the fun in that? We can nitpick the topographical features of the beautiful state of Ohio all we want but a day that has field work in it is a good day.

Monica here, with an update on the sediment we collected. Unlike Marcus I had a bit of a rougher time, as I was the one sacrificed to ride in the trunk with the sieves and freshly-collected samples. After much labor and help/interference from Amanda’s children we managed to collect the samples we needed from the river to be used further on our leaching adventures. They were collected as part of a project that I’ve been working on to determine the right ratio of Acid to Sample for leaching. Unfortunately the previous sample I leached was not collected recently enough so the fallout radio nucleotide Be-7 dissipated. By quickly leaching this sample we should be able to get the data were missing out on. They are currently in the oven, evaporating off the ditch-water and getting ready to be stripped in acid.

To make the field photos more enjoyable, we included some Gerber-baby level cuteness toddlers (Amanda’s children), who accompanied us into the field. Photo credit to Amanda’s wonderful au pair, Jenny. Enjoy! 

Wednesday, July 13, 2016

Staying STRONG in the lab

Monica here, celebrating my second week as a STRONG Scholar working in the geomorphology lab this July. I'm an incoming first-year and I hail from Shorewood Wisconsin (just north of Milwaukee). Currently I am considering doing Oberlin's 3-2 Engineering program with the ultimate goal of becoming an environmental engineer. I also am interested in Hispanic Studies and Politics. In my free time I enjoy folding origami lotuses, swimming competitively, and creating scavenger hunts.
Thus far at Oberlin, I have been working on some odds and ends in my research. From day one I started running calculations to test how changing the accuracy of parameters affects the efficiency (how active a sample is) in a program called Angle. The goal here was to discover how specific the parameters need to be to stay within the margin of error. On a larger scale, it helps us judge how much information we are required to know about the sample in question to receive accurate results when preforming calculations. The three parameters included sample composition, source height, and density.
I used a bunch of different methods of simplifying the composition percentages from nine elements into as few as one. Overall, I found that simplifying the data didn't have a very large impact. I was definitely surprised by that but at the same time I was relieved. Knowing that composition data isn't as important makes the process of running these calculations easier for others in the future.
Here's a graph showing five of the different methods I used with black lines above and below the x-axis marking the margin of error that thou shalt not cross:

I also studied a few different source heights and these turned out to be quite a bit more influential.

I found a similar pattern when it came to density as well.

Based on the graphs I made, it was apparent that these values needed to be somewhat correct to get accurate calculations. Because of that, my next step of lab work was to analyze 13 of the leachate samples from one of the labs previous expeditions to China. This presented numerous challenges, as leachate is the outer coating of sediment, separated using acid. The samples had a unique acidy smell and presented some difficulties in measurement. It was a double challenge to be using calipers for the first time on leachates that were fractions of millimeters thick. Not to mention, when the ordeal was over I had to pray that I washed everything thoroughly enough so it wouldn't get corroded. Despite my struggles in getting all the values to agree with one another, I was finally able to get results accurate enough to graph.
Ultimately I am really excited because my work will contribute to Amanda's research on a new way to more accurately measure Lead 210 and hopefully create a better system for quantifying this indicator that can be used to measure erosion.
Next in the process, Marcus and I will be leaching more samples to be examined later on and *fingers crossed* the hood will remain intact as the HCl evaporates. We also are all reading a series of Parsons and Foster papers (and their critiques) around the validity of using Lead 210 as an indicator of erosion which are laden with witty scientific dissing.
I'm hoping my next two weeks this summer of research will be just as enjoyable as the past two and I want to thank both Marcus and Amanda for facilitating this fantastic experience and helping me get adjusted. Geomorphology rocks!