Uncloaking mysteries of carbonate crystal growth is the goal of a research project this summer.
Jennifer Tonkin ’03 will try to grow dolomite crystals in gels at normal earth-surface temperatures. Growing dolomite hasn’t been done in the lab before except at high temperatures, Tonkin says.
“We’re hoping that the chemistry of the gel will change the crystals and temperature will no longer be a factor,” she says.
As an EXCEL Scholar, Tonkin is working with Kathryn Schubel, assistant professor of geology and environmental geosciences. “It’s an amazing opportunity. My friends at other schools are jealous that I’m getting to do this as a sophomore,” says Tonkin.
Dolomite is an important mineral found in carbonate rocks near oil and gas deposits and “may have something to do with oil being there,” she notes.
In addition, it presents a quandary to scientists because significant accumulations of dolomite are not forming at surface conditions, despite the fact that the mineral is common in ancient carbonate deposits, Schubel says.
Also, calcium-rich dolomite phases, discovered in modern environments such as the deep ocean, tidal flats, and non-marine saline lakes, are structurally different from ancient dolomites, the professor adds.
“These issues are known to geologists as ‘the Dolomite Problem’,” says Schubel.
One of Tonkin’s challenges is learning how to make the gel the crystals may grow in because it hasn’t been done since 1920, and the literature and methods are outdated, she says.
“We’re going to try to find a modern way to produce the gel. It’ll be trial and error,” the student says. “We’ve been working for three weeks already.”
Tonkin thought the experiments would be more or less laid out for her, but finds the opposite is true. In fact, she is expected to set up and run a number of crystallization experiments this summer. And while the professor planned to design the experiment with her, Schubel says, “the majority of responsibility regarding use of different gels and seed crystals will fall on Jen’s shoulders.”
Schubel describes Tonkin as a careful worker who has done well in her classes and is ready for the research.
A graduate of Montgomery High School in Skillman, N.J., Tonkin is an intramural bowler and a Kids in the Community volunteer. She performs in the wind ensemble, pep band, and concert band, and has participated in a Marquis Players’ charity benefit show.