NAU doctoral student using NSF grant to fund research into the mysteries of the Colorado Plateau

Doctoral student Alexis Riche studies the Colorado Plateau.

The Colorado Plateau is a 240,000-square-mile stretch of elevated land that stretches through the Four Corners area. Flagstaff sits at the southern end of this geographically varied, physically striking plateau, which has drawn scientists from throughout the world to study it.

Despite that, the Colorado Plateau remains a bit of an enigma for one simple reason—it is about 2,000 meters in elevation, which is noticeably higher than the surrounding areas. And no one is quite sure why.

Alexis Riche, a second-year doctoral student studying geology in Northern Arizona University’s School of Earth and Sustainability (SES), is hoping to answer that question in her research. She got a boost in that work when she was selected for the National Science Foundation’s Graduate Research Fellowship Program (GRFP), a prestigious national fellowship for STEM students. The fellowship, which provides three years of funding, will allow Riche to get a little more creative with her research than being funded by a specific grant allowed.

“I can broaden the scope of my research and really pursue other interesting things I find or skills I want to build as I progress,” said Riche, who earned her bachelor’s degree from George Washington University. “One of the exciting parts about this is I don’t have to decide what I’m going to do for my whole Ph.D. right now. I have the freedom to pursue things as they arise and I discover new things, so my research can evolve and stay relevant.”

Riche started at NAU as a master’s student, recruited by SES professor Mary Reid on an interdisciplinary project taking on the mystery behind the Colorado Plateau’s height. She switched to a Ph.D. after her first year, giving her the chance to spend more time on her research.

“Lexi has impressed me with her poise and with her willingness to be challenged, seek feedback and accept criticism so that she can advance as a scientist,” Reid said. “She also recognizes that science will evolve over the course of a Ph.D. and that it is important to seize opportunities. The GRFP should help her to do just that.”

Geological research

Most people in northern Arizona don’t think much about why the elevation here is what it is. It’s a high desert, said with a shrug as one tries to explain why it’s so different from the rest of Arizona. Or it’s “up the mountain” from Phoenix. But for geologists, that elevation, known as uplift, is a thorny question.

“This uplift is currently still unexplained, heavily debated and likely complex,” Riche said.

Her doctoral research, which she’s continuing this summer in Flagstaff, focuses on integrating geochemical, geophysical and thermodynamic data to propose an uplift mechanism for the physiographic feature that defines this part of the country.

“Uplifted plateaus like the Colorado Plateau lie at high elevations compared to their surroundings,” Reid said. “Various factors have been proposed for this, making this a subject of lively debate.”

Riche is using geochemical tools to examine whether the mantle under the Colorado Plateau region is unusually rich in water because of the way an oceanic tectonic plate was thrust beneath it. Hydration would have increased the buoyancy of this part of the continent and could have implications for other plateaus.

Women in STEM work

Riche had her first woman mentor in graduate school.

That wasn’t why, during her second semester at NAU, she joined Project Exploration of Recruitment of Earth Scientists (EXPLORES) and encourages students who are interested in STEM to learn more about geology, regardless of their field. However, that work did lead Riche to her secondary research—why women join and remain in NAU’s geology program even as women are underrepresented in STEM programs and fields throughout the nation.

The germ for this research, which has been submitted to the Journal of Geoscience Education, started when Riche, who had experience in chemistry, joined EXPLORES and started auditing labs, building relationships and connecting undergraduate STEM students with peers in the geology department.

“We started interviewing more advanced students in geology to get an idea of what they liked about the program, and we realized that we had the opportunity to really showcase why our department was attractive to women,” she said. “There were so many female students that wanted to talk to us.”

She focused on women, but, Riche said, women are only one of groups that remain underrepresented in geology and other STEM fields. Geology remains a male-dominated field and one that could benefit from more diversity in its practitioners.

“In general, it was difficult for me to navigate academia, both as a woman and a first-generation student,” Riche said. “Seeing as I favored science over the humanities in college, it was even harder to find someone I could relate to that could understand where I was coming from. Having representation in the field you want to go into is really important both for self-efficacy and visualizing that there is a place for you in this field, and I think that’s something geology lacks right now.”

The GRFP and next steps

Like most grant applications, the GRFP is lengthy and involved; successful applications require time and careful attention. Riche offered a few tips for any students interested in applying:

  • Give yourself time. Riche said she worked on the application over the course of three months, which allowed her to take breaks in between working on it, to edit and revise and to ask for and incorporate feedback from advisers.
  • Seek as much feedback as possible. Getting many reviews helped her refine her application.
  • Look at applications of previous winners. She said this allowed her to look at structure and figure out how to put together a good application.

With funding in place for the next three years of her education, Riche continues to focus on her research question and look for adjacent questions that may be worth considering as she tries to unpack the mystery of the Colorado Plateau’s uplift. She’s not sure yet what her post-doctorate plans will include, but she wants to do research. She’s particularly interested in laboratory science, an important but underrated part of geoscience.

Editor’s note: Four NAU students were selected for the National Science Foundation’s Graduate Research Fellowship Program. Learn more about the research of ecology student Kelly Jaenecke, astronomy student Schuyler Borges and astronomy post-baccalaureate scholar Jay Kueny.

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Heidi Toth | NAU Communications
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NAU Communications