Undergraduate Student Profile:
Carl Aquino
I graduated in May 2020, but more than a decade has passed since my freshman year at Penn State. I’ve lived in six cities in four states, along two coasts, worked nine jobs, and started two companies. I studied at five colleges across two universities and majored in Chemical Engineering, Industrial Engineering, Music Composition, Finance, Earth Science and Policy, and Meteorology—all before completing my bachelor of science in earth sciences.
Why come back to Penn State to study climate science? There are many reasons, but one stands out in particular: in Los Angeles during fall 2017, a certain ‘Avenger’ was in town filming the movie Avengers: Infinity War and wound up being my roommate for a few weeks. One night over Chinese food, I shared that I was quite conflicted about leaving everything to go back to school. His advice changed my life: “Do the thing that you’ll want to get really, really good at, because humanity will be grateful.” And here I am, graduating from one of the best programs I could have ever hoped to be a part of.
Oddly enough, in some sense I am just beginning. This fall I started graduate school at Penn State in the geosciences department. It’s the next step in my journey—a real mission given to me by an ‘Avenger’—to save the world.
Master’s Student Profile:
Hailey Mundell
I’m from a rural area in mid-state South Carolina, and I grew up on a farm with chickens and horses. I did my undergraduate studies at Clemson University, earning a bachelor’s degree in geology.
My undergraduate research focused on quantum-mechanical modeling of hollandite as part of a polycrystalline ceramic waste form, with the intent to use its crystalline structure to store radioactive cesium—a common component of high-level nuclear waste streams.
At Penn State, my master’s research is petrology-oriented, but still includes some computational modeling. My adviser is Andy Smye, assistant professor of geosciences, and my research seeks to constrain the impact of fluid flow through eclogite-facies metagabbros from the Tauern Window in the Alps. These eclogites have been subducted to extreme depths of about eighty kilometers and subsequently exhumed to the surface, where we can access them and perform detailed petrographic research.
During subduction, the increasing heat and pressure causes fluid to be released from the crystalline structure of host minerals as they break down—a process termed devolatilization. The free fluid, primarily water and carbon species, flows through the slab to the mantle wedge, where it lowers the melting point of the mantle. This results in arc volcanism. The fluid might also introduce weakness into the subducted rock by raising pore fluid pressure, causing seismic and aseismic events. It’s impossible to observe these events in situ, so petrographic research is important to understand what occurs tens of kilometers below the surface. Fluid is preserved in eclogite samples as quartz, or carbonate, veins. Around the veins, the mineralogy of the eclogite changes along a reaction selvage. The gradual change in chemistry across the reaction selvage allows detailed analysis into how long the fluid was flowing and what soluble elements it took elsewhere.
Recently, I have been focusing on comparing the garnet chemistry of vein-altered eclogites to corresponding unaltered eclogite samples taken further from the vein, using electron microprobe data. Garnets grow as the rock is metamorphosed, preserving a compositional record of past conditions. The unaltered samples provide baseline conditions experienced by all of the rocks, which might have been obscured or modified by diffusion induced by vein activity. After clearly defining the pressure-temperature conditions and mineralogical changes experienced by all of my samples—using phase equilibria modeling—I will have a clear backdrop against which to closely analyze the changes in texture and mineralogy found in the reaction selvage around the veins. These chemical variations will allow me to interpret the timescales and length-scales of fluid-rock interaction.
Doctoral Student Profile:
Joanmarie Del Vecchio
I didn’t plan to study science in college, but I got hooked by field trips and stories of the Earth’s history in an introductory geology course I took in Southern California.
I became interested in geomorphology, and as an undergraduate student I worked on projects studying how the desert landscape responded to changes in climate and tectonics. When I chose my graduate program, I was just as surprised as anyone to find myself studying a totally different landscape in Appalachia in a return to my home state of Pennsylvania.
I began as a master’s student tasked with telling the story of landscape change at the Susquehanna Shale Hills Critical Zone Observatory with my adviser Roman DiBiase, assistant professor of geosciences. After a summer of mapping the steep, bouldery slopes of Tussey Mountain and studying high-resolution topographic maps of the Valley and Ridge, it was obvious this landscape’s story was complex.
Previous researchers had suspected the central Appalachian landscape was heavily shaped by ancient permafrost processes that had dominated the landscape at the heights of previous glaciations. Using lidar maps and cosmogenic isotope dating, we confirmed the legacy of permafrost on central Pennsylvania’s landscape and were able to hypothesize how cold-climate processes changed the pace and pattern of landscape evolution compared to warm climate periods.
During my master’s thesis research, it was clear that central Appalachia had many stories to tell, and I wasn’t going to begin to tell them all in a two-year project. I decided to stay at Penn State for my doctorate, and I designed an interdisciplinary research plan to better tell the story of climate, ecology, and erosion in ancient permafrost landscapes.
I have been working in the bog in the Bear Meadows Natural Area, near Boalsburg, Pennsylvania, investigating the sedimentary records on both the hillslopes and under the peat in the bog itself. I was thrilled to involve Sarah Ivory, a recently hired assistant professor who studies palynology, as I planned my project in pollen-based interpretations of the bog sediments. By combining methods to track ancient erosion and ancient ecosystem patterns, we have a holistic understanding of what Pennsylvania looked like as its landscape transitioned from glacial maxima to the warm interglacials that followed.
Working in ancient permafrost systems has sparked in me an interest in the modern Arctic, whose permafrost is both vulnerable to thaw and a potent store of carbon that, if released, could have massive implications for global climate. I loved being able to tell stories of ancient permafrost—might these stories help predict what will happen to our modern permafrost? And can studying modern permafrost landscapes further help me make interpretations from sedimentary records?
To explore these questions, I proposed a project that took me to Los Alamos National Laboratory in summer 2019. There I worked with scientists who used field remote sensing and modeling to study western Alaska’s permafrost landscapes and ecosystems. The highlight of this project was fieldwork on the Seward Peninsula, where I could see permafrost landscapes thawing and changing in real time. That project affirmed my desire to use the past to help predict the future, and to be involved in interdisciplinary projects that draw connections between the living and nonliving parts of ecosystems.
As I finish up my dissertation at Penn State, I’m excited to see what the future brings. I hope I can keep doing exciting fieldwork while developing new skills and techniques. When I’m not working, I enjoy exercising, board games, and trivia with friends, and trying, but not always succeeding, to sew and crochet my own gear and clothes. I’m so grateful to have found a great bunch of colleagues and friends in the geosciences department with whom I can share science ideas and happy hours.