Research by Erika Rader ’07, assistant professor in the Department of Earth and Spatial Sciences at the University of Idaho, melds planetary science, volcanology, and igneous petrology.
Bryce Ducharme
What can crystals and glass on Earth tell us about the history of Mars? That’s one of the many questions that Erika Rader ’07 is hoping to answer through her interdisciplinary research that melds volcanology, planetary science, and igneous petrology, or the study of rocks that form from cooling lava and magma.
Since the inception of space missions to Mars in the 1960s, researchers have been driven by a central question: Could the planet ever have sustained life? While we now have evidence that water once flowed on the Red Planet, environmental factors like temperature and seasonality of water would have also played a key role in habitability. This is where studies of lava come in.
“There’s a lot of debate about whether Mars was hot and wet, or cold and dry, or some other combination,” says Rader, who is an assistant professor in the Department of Earth and Spatial Sciences at the University of Idaho. “We don’t have the opportunity, necessarily, to analyze planetary samples that can tell us those things about past environments. But Mars does have lava that you can see from satellites.”
And the appearance of cooled lava can give important information about the environment into which it flowed. For example, if lava cools quickly due to an interaction with water, the surface will appear dark and glassy. But if it flows into a desert where there’s not a lot of water and it cools in an ambient air temperature environment, there will be crystals evident in the texture of the surface, Rader explains.
She and members of her lab have been building an image library of lava flows on Earth, using specialized imaging instruments called spectrometers, along with data from detailed rock studies that show the type of crystals and proportion of crystals to glass for those flows. In a recent study, Rader and a student of hers tested the use of a visible near-infrared (VNIR) spectrometer to investigate a relatively young lava flow at Jordan Craters, Ore. VNIR tools operate at wavelengths that can help see textures and mineral content in the rock, indicating lava-water interactions. By comparing images taken in the field to the analysis of samples that they took back to the lab, the team found that the imaging technique worked well at providing on-site data, adding a new tool to their arsenal.
“We can now make fundamental measurements of the amount of crystals in solid lava rock without having to break and take the rock to a laboratory,” says Rader. “This is helpful for quickly scanning surfaces for evidence of lava-water interactions.”
The long-term goal is to be able to match up images from Earth to images taken of the Martian landscape by satellite and rover- based spectrometers to help pinpoint where and how much water may have existed on the planet. This type of information could inform sampling locations for future missions, giving scientists a better idea of where they might find signatures of past life on Mars.
While planetary science is a major thrust of her lab, Rader explores a wide range of questions in her work, including how to mitigate the hazards of volcanic eruptions. She says many of these inquiries arose in her first class in volcanology at Colgate — where she majored in geology — that solidified her career path. She remembers compiling a long list that she shared with professors Karen Harpp (earth and environmental geosciences and peace and conflict studies) and William Peck (Department of Earth and Environmental Geosciences).
“My work does tie back to that wild Word document full of questions,” says Rader. “The things that interested me then are the things that I can now actually pursue, which blows my mind. They are the things I am interested in to the point of pushing the boundaries of what we know.”
Rader was awarded the University of Idaho’s 2023 College of Science Early Career Faculty Award.