Mary Tkach’s fascination with the natural world started early in her life. Her parents encouraged her and her brother to play outside often and would sign them up for scouting clubs and take them camping. Later, in seventh grade, Tkach’s teacher explained the science behind the rock cycle. Her curiosity was piqued when her teacher used mining chocolate from cookies to explain the processes that create and transform rock in the Earth’s crust. Tkach was hooked.
“She used very relatable items to explain very common phenomena that takes place on the Earth’s surface,” Tkach said. “Once the chocolate chips were mined from the cookie, it would be very difficult to put the cookie back together in its initial condition. She made me want to learn more about the Earth.”
Tkach went on to earn her bachelors of science degree in geology from the University of Pittsburgh, studying with the National Energy Technology (NETL) Professional Internship Program along the way. She credits her first Oak Ridge Institute for Science and Education (ORISE) mentor at NETL, Barbara Kutchko, for teaching her valuable lessons during the internship.
Tkach was unsure of where to go next. However, having already interned with NETL once, she knew that she would again find direction through ORISE, so she applied for a Mickey Leland Energy Fellowship (MLEF) while enrolled for her masters in geology.
I believe that if it wasn’t for ORISE, I think that I would not have earned enough credentials from my undergraduate studies alone to qualify for the graduate schools that I attended,” she said. “ORISE also ignited a spark of scientific curiosity in me to really thrive and succeed in graduate school, and my graduate school studies, experiences, and grades, in turn, helped me to land my current role as a geologist.
The MLEF program provides students with fellowship opportunities to gain hands-on research experience with the Department of Energy (DOE) Office of Fossil Energy and Carbon Management. The program’s mission is to strengthen and increase the pipeline of diverse future science, engineering, technology, and mathematics (STEM) professionals. Joining MLEF would turn out to play a large part in her future as a scientist as she pursued her masters in geology.
“I was hoping that I would be motivated and inspired to find a thesis topic after a summer full of research, but it turned out that my MLEF research became my thesis,” Tkach said.
She returned to NETL for her MLEF appointment and, alongside her mentor Sean Sanguinito, joined a variety of important projects focused on topics such as mitigating environmental impacts of resource mining, improving offshore well integrity and determining the feasibility of storing carbon dioxide deep underground. This research involved observing geochemical reactivity between carbon dioxide and certain geologic formations, such as the Utica shale, Marcellus shale, Mt. Simon sandstone and Amherstburg limestone.
Shale is vital to carbon capture and storage processes as it can safely contain carbon dioxide deep underground. Sandstones are are very porous, like a sponge, and also have the ability to hold large quantities of carbon dioxide. By injecting carbon dioxide below a shale formation and into a sandstone, one can reduce greenhouse gas emissions to have a positive impact on climate change and polluted air.
However, the bulk of Tkach’s research was on investigating the Amherstburg limestone of the Michigan basin, a widespread and low-porosity rock formation deep within the Earth. She focused on studying its ability to serve as a seal to prevent the release of sequestered carbon dioxide. Because of the specific geochemistry associated with limestone, it has been hypothesized that carbon dioxide may precipitate calcium carbonate minerals, such as calcite, on the surface of the limestone, ultimately reinforcing the limestone’s ability to act as a seal.
Tkach and her team hope their research will lead to easy and safe ways to store carbon dioxide within the Earth, which may help with climate change.
After completing her MLEF fellowship, Tkach graduated with her masters, coming out of academia with a 4.0 GPA and a Boone Pickens School of Geology Graduate Service Award under her belt.
She believes the two research opportunities helped to nurture the budding scientist within her. Since graduation, she has gotten her dream job as a geologist at the Idaho Geological Survey, where she gets to spend weeks in the field collecting samples every summer. She says her experiences at NETL through ORISE helped her to achieve this dream.
“I believe that if it wasn’t for ORISE, I think that I would not have earned enough credentials from my undergraduate studies alone to qualify for the graduate schools that I attended,” she said. “ORISE also ignited a spark of scientific curiosity in me to really thrive and succeed in graduate school, and my graduate school studies, experiences, and grades, in turn, helped me to land my current role as a geologist.”
The NETL Professional Internship Program and the MLEF Program are administered by the Oak Ridge Institute for Science and Education (ORISE) for the U.S. Department of Energy. ORISE is managed for DOE by ORAU.