Geologist Elizabeth Cottrell sifts through debris near Sugarloaf Peak in the Aleutian Islands. Some of the volcanic ash in the area contains minerals that help scientists learn more about continents. (Michelle Coombs)

When she was a girl growing up in northern Vermont, geologist Elizabeth Cottrell loved hiking and doing science experiments with her dad.

“I liked knowing and understanding how things worked,” she says.

Her dad, who was an engineer, had answers for things she wondered about, such as how a compass works or why the sky is blue.

That joy of understanding the world helped Cottrell, 41, shape her career working for the National Museum of Natural History’s department of mineral sciences at the Smithsonian Institution. As curator-in-charge of the Smithsonian’s rock and ore collections, she oversees scientists-in-training who are preparing and analyzing rock samples and figuring out what the data reveals about Earth. She spends a lot of time writing to share the results of the research, which is all about helping solve such mysteries as how our planet formed about 4.5 billion years ago and what secrets volcanoes might reveal about Earth’s mysterious insides.

Cottrell traveled by helicopter to the islands in 2015 to collect samples to help explain how the Earth created continents. Here, she is at Tanaga volcano, Western Aleutians. (Dan Leary )

In 2015, Cottrell led a team of geologists on a research trip to study Arctic volcanoes in the remote Aleutian Islands (pronounced uh-LOO-shen). Volcanoes, she says, provide the best way to get precious samples from deep inside Earth.

To get there, they flew 3,300 miles from Washington, D.C., to Anchorage, Alaska. After days of grueling underwater helicopter escape training (to improve their chances of survival in case their helicopter landed and flipped over in the ocean), they took a three-hour airline flight to the remote island of Adak, where they boarded the Maritime Maid, a boat that would be their home for three weeks.

Each day on the mission, they flew by helicopter to hard-to-reach volcanic islands for samples that might give clues about Earth’s origins.

Cottrell finds volcanic tephra on Buldir — one of the most remote volcanos in the world. (Katherine Sheppard)

The team hiked treacherous rocky hills and dug samples with trowels, or small, handheld shovels. They filled plastic bags with samples to return to home base. Evenings were spent sorting and labeling the samples.

Their most important sample was a special kind of “tephra,” or volcanic ash, made up of glass and minerals. One of those minerals is called olivine, which is strong enough to trap and preserve magma, or liquid rock.

“It’s a little time capsule,” Cottrell explains.

The tiny drops of magma freeze to form volcanic glass. The scientists hoped the tephra samples would contain the minerals they needed to provide clues about how Earth created continents.

You can watch a video of her trip at v=Q9ebwokEUJk. (Ask a parent before going online.)

Cottrell, who is a mom to an 8-year-old girl and a 5-year-old boy, calls herself a “rock person.” She says geology gives us the ability to better understand Earth.

“This planet started as a big, mixed-up ball of metal and rock,” she says. “How did we get from stardust to skyscrapers . . .? I love geology’s ability to explain the world around me.”

Cottrell is pictured in her office at the National Museum of Natural History. The blue box is a piston-cylinder press. It's used to re-create conditions of high temperature and pressure, deep within the Earth. (Eris Qian)
So you want to be a geologist?

Kids who want to become geologists should spend plenty of time outside digging in the dirt, says geologist Elizabeth Cottrell. “Kids are often amazed to find out how much we don’t know,” she says, “and how much they can contribute.” To prepare for a career in science, she also recommends spending time:

•Focusing on learning to be a good writer.

•Exploring the outdoors.

•Testing ideas.

•Playing and observing.

•Picking up rocks and taking notes about your findings.