Over the summer of 2015, I started the preliminary research on the Devonian portion of the BETA Project. The Devonian section focuses on how changes in the biosphere and atmosphere are related and can be observed in the rock record. To help prepare for the BETA Project, I researched how the planet, and more specifically Iowa, changed over the course of the Devonian.
Through my research, I learned how the Devonian Period is characterized by a couple of major interconnected changes. First is the radiation of land plants. This marks the first time in Earth’s history that multi-storied forest ecosystems are found. This period is also defined by a global anoxic episode as evidenced by black shales that deposited during this time. This episode is believed to be connected to the influx of organic matter as a result of these widespread forest ecosystems. Additionally, the chemical composition (oxygen and carbon dioxide) of the atmosphere changed as a result. This can be observed by looking at carbon isotope ratios in limestones that were deposited during the same time period. Iowa, which underwent many transgressive and regressive cycles in the Devonian, is characterized by Devonian limestones and shales. By looking at the isotopic composition of Devonian rocks sampled from the Cedar Valley area, we can find links between the atmosphere and biosphere during this period.
I helped to narrow down what stages of the Devonian we would look at in order to collect rock samples. I was supposed to find specific locations to collect samples from, but sometimes things just don’t go the way they’re supposed to. Since this project is still in its fairly early stages, there’s still time for that though! We have many more rock samples to collect.
One of the other important aspects of my research was going to NASA Goddard Space Flight Center in July to meet with our collaborators. We discussed with Dr. Jennifer Stern, an isotope specialist, what we would need to do to get our samples ready for analysis at NASA, including information on sample sizes and standards.
Though the BETA Project is still in its early stages, the foundation has been laid and the project is well on its way. I am very happy to have been a part in helping start out this project.
--Katie Patrick