Summer on the James: Geology student dives deep into field research
Zach spent her summer examining the geological composition of natural outcrops in the Seven Islands region about 50 miles northwest of Richmond. The makeup of these outcrops is subject to debate among geologists, some of whom argue that the exposed rocks’ composition suggests the presence of a geologic mélange —a French term describing a mixture of rocks that fuse together along two colliding plates at or near the seafloor. Zach’s primary goal was to contribute to ongoing conversations about Virginia’s geologic history in the James River region, particularly regarding its presence of a mélange. Fortunately, the river’s natural outcrops created samples ripe for analysis.
Previous academic experiences in the geology department compelled Zach to pursue summer research through William & Mary. She recalled her structural geology class, taught by professor and her now-adviser Christopher 'Chuck' Bailey, as a pivotal moment in her decision to seek out supplementary experiences within the department, both on and off campus.
“For me, it wasn’t easy, but it clicked for me, so that’s when I knew I really wanted to work with him,” Zach said.
Zach also said that the department’s inclusive atmosphere empowered her to pursue summer research. As a non-traditional student who transferred from Thomas Nelson Community College in 2019, Zach attributed her research success partially to academic mentors within the department who helped her follow her passions for tectonic geology.
“I really, really appreciate the geology department,” Zach said. “I’m 27 now, so that was a big fear of mine, that I would stick out. And everyone there is so kind and so welcoming ... I wouldn’t be here if it wasn’t for them.”
From her strong academic foundations, Zach forayed to the Seven Islands for the first time in mid-June, canoeing along the James and noting the outcrops’ structural features. She examined the lineation, foliation and mineral composition of outcrops and surrounding rocks, discoveries that would eventually aid in her analysis of the region’s geologic past. Her initial trips were fruitful, especially since COVID-19 was fairly unobtrusive in interfering with her open-air research endeavors — but Zach said that she had to experience some ‘on-the-job’ training during her first excursion.
“Nothing really changed about my research (as a result of the pandemic), but there were extra steps on top of learning new things,” Zach said. “For example, I had no idea how to canoe, so I learned how to canoe right there on the spot.”
She traveled back to the Seven Islands an additional two times, once during the summer and once during the fall semester. With each successive trip, Zach was able to visit more outcrops and collect additional samples, which she then brought back to analyze and cut small sections of the samples in campus laboratories. Her work with sedimentology and compositional analysis enabled her and Professor Bailey to weigh in with their thoughts regarding the proposed ‘mélange.’
“We went in thinking that this was a mélange, and what we came out with is that we are no longer sure it is,” Zach said.
Moving forward, Zach will examine the rock samples she and Bailey collected. She plans to conduct strain analysis, which will help further elucidate the samples’ grain compositions and the outcrops’ geologic makeup. Looking back on Zach’s research, Bailey said that her project highlighted the natural beauty of the James River region, while also using modern instruments to accomplish her analytical goals.
“Terri’s research is casting a critical eye on a proposed ancient tectonic plate boundary hidden in the placid central Virginia countryside,” Bailey said. “Using new technology (LiDAR and drone photography) and old technology (a canoe and compass) she’s been able to map the geology at a scale 10 times more detailed than previous researchers. Her research is demonstrating that the rocks and structures are both complex and beautiful.”
Bailey also said that Zach’s research did a good job bridging the divide between hands-on research and conventional classroom learning, which sometimes trips up students as they explore research opportunities as an undergraduate student. Bailey praised Zach’s willingness to step outside the classroom and apply her knowledge to new experimental settings.
“I’ve been impressed with Terri’s desire to learn and take on new challenges,” Bailey said. “She also learned how difficult and different doing field science is from traditional classroom work - instead of being discouraged by early mistakes she’s learned and grown throughout the progress of this project. Terri’s climbed up the steep learning curve for doing effective field geology.”
While she still plans to pursue additional research with Bailey during the fall semester, Zach’s research experiences are extending well beyond the summer months as she takes a new approach reflecting on her options after graduating from William & Mary next year. After falling in love with conducting field work and explaining her research to newcomers to geology, Zach wants to apply to a graduate geology program, where she will combine her newfound loves for teaching and hands-on research.
“The long-term goal for me now is becoming a professor,” Zach said. “... Closer in the future, I didn’t realize I would like field work so much, so becoming a fieldwork geologist is now my priority. I want to go to grad school, but I want to look into schools that have that fieldwork aspect, because it was a fun thing for me that I didn’t expect it to be.”