You don't need a shovel to find out what's happening underground.
Using advanced sensing technology, near-surface geophysics allows us to peek under the Earth's surface from the ground, the sky or even space, explained Assistant Professor of Earth Sciences Sina Saneiyan, who joined Binghamton University in the fall of 2024.
Saneiyan grew up in the mountains of southern Iran and has been fascinated by the Earth and nature since early childhood. After college, he worked as a mining exploration engineer, visiting beautiful places to assess their resources - for the purpose of extracting them.
"At that point, I realized that extracting resources can be destructive to the environment," he reflected.
He shifted focus, coming to the United States in 2015 to pursue a doctorate in Environmental Sciences at Rutgers University, with a focus on geophysics. After earning his degree in 2019, he spent three years at the University of Oklahoma.
Everything in our lives ultimately depends on the ground beneath us. Our houses and roads rest upon the Earth, and many of the resources we use to create material culture are found within and upon it. And the Earth can also kill, via dangers such as earthquakes and landslides.
Being able to see underneath that surface is critical for avoiding or mitigating the dangers, as well as discovering needed resources or gaining insight into the Earth's deep past.
"It's just like when you go to the doctor and say, 'I have a pain in my chest.' The doctors don't start operating on you; they use X-rays, MRIs or other imaging techniques to see what's going on in your body," Saneiyan explained.
From gas wells to life on other planets
Near-surface geophysics looks at the Earth's surface to a depth of about 100 meters and lends itself to a wide range of applications, reflected in Saneiyan's broad research interests.
At Binghamton, Saneiyan is leading two research projects. Funded by NASA, the first explores the use of sensors to determine whether an alien planet is potentially habitable. Sensors could be mounted on vehicles similar to NASA's Mars Rovers, or drones.
The technology, however, was inspired by an earthly location: a sulphur-rich spring in Oklahoma whose Indigenous name, Zodletone, translates to "vomit water." Around 100 years ago, it was a prime destination for the wealthy, who considered its foul-smelling waters medicinal.
In addition to its high sulphur content, the water is also very salty - conditions that would seem to make it less than welcoming for most forms of life. Interestingly, it's home to thriving microbial communities of a type identical to those at the very start of life on Earth. So far, his lab has uncovered geophysical techniques that can detect biosignatures and seasonal changes.
"We proposed to NASA that if we can use these geophysical techniques to characterize this harsh environment, which is similar to environments found on other planets, then we can find habitable worlds," Saneiyan explained.
A second project tackles the problem of abandoned oil and natural gas wells, estimated to number more than 3 million across the United States. Once a driller was done with a site, they would simply take their pumps to another well, leaving the hole in the ground, Saneiyan said. Much of this activity began with the first commercially drilled oil well in the late 1850s and the location of many wells went undocumented.
However, most of these wells drilled after the early 1900s have a feature in common: drillers used a casing made from a steel alloy that's magnetic and can be detected by a device known as a magnetometer. The problem: the magnetometers used in research costs tens of thousands of dollars - and no one knows where to start looking, even if you mount them on drones.
"So, do we cover the entire United States? It's not feasible," Saneiyan explained.
But what if you already had a magnetometer with you right now, one that you carried with you everyday?
It turns out that nearly all smartphones are equipped with an internal compass - and compasses detect magnetism. Working with a colleague on an Oklahoma ranch in 2022, Saneiyan tested out his idea and found that it worked; his research was published in the Journal of Applied Geophysics. He currently has a patent pending (US Patent App. 18/444,665, 2024) for the use of cell phone magnetometers in finding abandoned wells.
"Because they are ubiquitous and available in people's pockets everywhere, what if we have citizen scientists or just normal people going hiking turn on their magnetometer and start collecting data?" he speculated. "Would that work?"
The well casings have a distinct signature when compared to other magnetic objects, such as the rebar used in building construction. Saneiyan is working with Assistant Professor of Systems Science and Industrial Engineering Sara Kohtz on a way to distinguish that signature and locate the wells using artificial intelligence. Meanwhile, one of his graduate students is developing an app that would make the data processing simple.
"Let's say you want to purchase a property that's a couple of acres and you want to know if there's an orphaned well hidden in there. Orphaned wells are dangerous; they're conduits of methane into the atmosphere and in rare cases they can explode," Saneiyan said. "They would affect the purchase price of the property. So simply, you can download an app and do a quick survey yourself."
He also has other research interests, including the unstable soils that lead to dangers such as landslides. Electrical signals from the Earth's subsurface can indicate that a slope failure is imminent; in his lab, he has an instrument that can measure these underground electrical changes, one of the few in the country. He currently has a proposal before the National Science Foundation to use this technology as a way to monitor vulnerable slopes.
With applications ranging from residential neighborhoods to outer space, Saneiyan's discipline is highly versatile, reflected in his diverse research interests.
"A near-surface geophysicist is a jack-of-all-trades for Earth Sciences," he acknowledged. "We detect what's going on in the subsurface and then we collaborate with other scientists who can explain it."
