Undergraduate Student Profile:
Nancy Weinheimer
This year, I am graduating with a degree in geosciences from the College of Earth and Mineral Sciences after applying to and arriving at Penn State with different majors. I knew I wanted to study science in some way that would improve the sustainability of the human relationship with nature, but I couldn’t find the right fit for me in other fields. I also knew I loved being outside and applying fundamental sciences to real time environmental problems. Luckily, a general academic adviser in the college pointed me toward the geosciences department. I was intrigued by the cutting-edge faculty research, the fieldwork opportunities in almost every course, and the inherent application of all subject matter to solving real-world problems. After meeting with Dr. Feineman and taking GEOSC 001, I knew that geosciences was exactly what I wanted to pursue. Throughout my time here, I have been involved in various research projects, even traveling to the Western Alps for fieldwork and presenting my results at the 2019 AGU Fall Meeting. I am so grateful for discovering my passion for geosciences here at Penn State!
Master’s Student Profile:
Hanna Leapaldt
Growing up in small town in Minnesota, my affinity for lakes developed early. During grade school, my love for lakes was purely recreational and had nothing to do with science. In fact, science was my least favorite subject. Throughout high school, I switched “what I “wanted to be when I grew up” often, but a geoscientist was never an option. All I had was a simple goal of helping people in some way or another.
Eventually, I ended up getting my bachelor’s degree in environmental science. Thanks to some incredible educators at my undergraduate alma mater— University of Minnesota, Duluth—I learned that surprisingly I could combine my love of lakes with my goal of helping people through a career in science. During my undergraduate studies, I did research that used lake sediment cores to help create records of climate variability in the Great Lakes region. These records can be used to help predict future climate variability in the region. I was captured by the fact that lake mud could help humans know how to best prepare for future climate change.
Eager to stay involved with this work, I sought a master’s degree working on the terrestrial paleoclimate archive. Here at Penn State, I have the opportunity to work under Miquela Ingalls, assistant professor of geosciences, doing just that. Our work is using the carbonate rich sediments of Green Lake, New York, to determine if microbes in sediment pores are changing what the sediments record.
Typically, paleolimnologists use chemical signals in lake carbonate sediment to reconstruct a history of environmental parameters surrounding the lake’s region. These parameters include evaporation-precipitation balance of the region, the lake’s primary productivity levels, and even past carbon dioxide levels to create a cohesive climatic history of the area. In the past, this work has focused solely on the physical and chemical contributions to the signals of the lake sediments.
Enter biology. It turns out that microbiology might contribute to lake carbonate signals just like other environmental parameters. When microbes are active in the sediment, they can cause carbonate to precipitate or dissolve. This can change what signals the sediment records and could cause a biologic signal instead of the other typically interpreted environmental signals. My project is to use the Green Lake carbonates to tease apart the effects of biology from the effects of other environmental factors like the precipitation/evaporation balance. The end goal is to determine the characteristics of the carbonates—appearance, composition, grain size—that are more susceptible to a signal influenced by microbiology.
By determining which types of carbonates are most likely recording biologic signals versus other environmental parameters, I hope to contribute to a less exclusive or more accurate reading of lake sediment’s chemical signals. This way, lake sediments will provide more informative climate records and better help predict future climate change in terrestrial spaces.
My favorite part of this work so far is the interdisciplinary nature of it. Geobiology is an up-and-coming field and very new to me. I’ve had the chance to do both traditional geochemical analyses and fascinating geobiological work on my samples. I’ve learned how to extract the DNA from the sediments so that they can be sequenced. Soon I’ll get to learn how to interpret that sequenced DNA and figure out which microbial species are present in Green Lake. Since at Penn State, I’ve picked up that those microbes are unavoidably linked to mineral formation both past and present, so studying modern geomicrobiology seems one of the best ways to unlock even more secrets kept by the terrestrial rock record. And if I can continue to use lakes to do so, all the better.
Doctoral Student Profile:
Watsawan (Fai) Chanchai
I am a first-year graduate student from Phatthalung, Thailand. I enjoy warm weather and being in a paddy field. Rice is a key to my heart, but I also have fallen in love with carbonate rocks. I get excited every time I see limestones fizzing with acid, and I love that they also capture so much knowledge about ancient marine environments and past climates.
I study sedimentary geochemistry at Penn State with Dr. Kimberly Lau. The Cambrian explosion marks a major biotic turnover and involves an increase in animal disparity and diversity in fossil records. However, the role of environmental changes during the Ediacaran–Cambrian transition is strongly debated. We are using multi-redox proxies—uranium, cerium and iron—to reconstruct redox conditions across four different study areas—Nevada, Mexico, Mongolia, and South Africa. If the record of redox fluctuations is primary and occurs globally, we can challenge the role of redox variability as a trigger to the biotic turnover. This summer I will be in working in the Laboratory for Isotopes and Metals in the Environment (LIME) to prepare my samples for rare-earth-element analysis and fly to Michigan State University to measure the iodine-tocalcium+magnesium (I/[Ca+Mg]) ratios. Besides all the fun in lab, I will also travel to Colorado College to attend my bachelor graduation ceremony—Class of 2020. Whoo-hoo! I cannot wait to be in the mountains and meet all my friends and mentors. They are my biggest supporters and spark my interests in justice, equity, diversity, and inclusion work.
As an underrepresented student in my previous institution and major, I found a safe space with people who share similar experiences and perspectives. They listened to me and accepted me as I am. While there, I had an opportunity to grow, express my true self, and achieve my own goals. I am now part of the diversity, equity, and inclusion (DEI) committee in geosciences at Penn State because I want to amplify the voices of others, provide equitable resources, and support underrepresented groups in the geosciences. My ultimate goal is to provide accessible resources and build a community where we all can respectfully share opinions and make a positive impact in our own way.
For this past year in Happy Valley, I have gained tremendous support from faculty, staff, and our graduate students’ community. Among all the uncertainties in this world, their positive energy is contagious and grounding. I am hopeful for my continuous journey here.