Rosemary Knight was finishing her PhD in geophysics in 1985 when she told her adviser, a leading light in the field, that she wanted to be a hydrogeophysicist.
The Stanford University veteran stared at the young Queen’s grad.
“What’s that?” he asked.
Dr. Knight went on to establish a new field in science, using geophysics methods to study water quantity and quality underground. She is now the first woman and second Canadian to win the highest honour of the Society of Exploration Geophysicists, the Maurice Ewing Medal.
The common way to study groundwater is through drilling wells, but one well only gives information about a small area. Dr. Knight has developed ways to scan broad areas without drilling. It’s like medicine, she explains: Why cut open the patient when you can scan from the outside?
She scans underground from a distance – from the surface, a helicopter, even satellites.
One example: satellites detect the minute rise and fall of the Earth’s surface – just millimetres of change – in a farming area of California’s Central Valley. The surface drops as farmers irrigate with groundwater and rises when water is recharged during the winter. Another: rows of sensors on California beaches measure electricity under-ground. This reveals where extracting groundwater has brought in salty ocean water, because salt conducts electricity better than freshwater.
Born in Wales, raised in Pittsburgh and Southern Ontario, Dr. Knight came to Queen’s already interested in geophysics. (She recently found her old Grade 13 guidance workbook, which asked what her parents wanted her to do after high school. “Whatever I want to do,” she wrote.)
While at Queen’s she met prominent geophysicist Dr. Ed Farrar, who passed away in 2020. She was one of the very first two women to take Dr. Farrar’s class, “and he made sure to tell us he wasn’t going to change the way he taught or talked.” But by the end of the semester he had offered her a summer job doing potassium-argon dating (reading the history of rocks by the amount of these elements in them).
“He said to me, ‘You should stay and do your master’s with me and then go and do your PhD at some big-name West Coast school like Stanford.’ There’s the difference a fabulous mentor can make.”
At Queen’s, she learned to use math and physics to understand Earth processes, but groundwater wasn’t yet part of her life.
Dr. Knight has developed ways to scan broad areas without drilling. It’s like medicine,
she explains: Why cut open the patient when you can scan from the outside?
One summer she had a job with Amoco in Calgary, learning to read data from instruments down a well. In a larger sense, she started to become interested in reading signals to interpret the geology of the subsurface, “and in particular, what is the fluid content?
“Realizing the huge potential for taking these geophysical measurements that… were commonly made for exploring for oil and gas,” she applied them to groundwater.
After getting her PhD at Stanford, she worked at the University of British Columbia until 2000, when a job offer from Stanford brought her back there. She’s still at Stanford, though she returns often to the Gulf Islands of B.C.
Setting out in an unexplored field has disadvantages, she says. There are no mentors, no guideposts.
“Now that I’m at the age where I’m mentoring young people, I realize how helpful it is to have people who have worked in the field, who are connected to more senior people.”
As well, “you do have to worry about being accepted as a field.” Granting agencies still don’t know what to do with her.
“It was the environment that I found in geological sciences at Queen’s that piqued my interest in research,” she says. “I remember very clearly one day working in Ed [Farrar]’s lab, I asked a question, we sat down, and it was four hours later that we got up. The whole experience of one-on-one, faculty-student interaction, mentoring, learning, was just fantastic.”
