April 21, 2021 | Oceans, WaterAlumni News
April 15, 2021 | Oceans
March 29, 2021 | Ecology & Conservation, Oceans, Technology
By Catherine Clabby
All scientists are explorers to a degree. They hunt down mysteries in their fields and try to convert unknowns into discoveries. Duke geochemist Emily Klein does all that. But more. Unlike many modern-day researchers, she also travels to places that very few people will ever see.
For decades, Klein has studied stretches of ocean seabed that generate new crust on Earth’s ocean floors. Often deep under water, these are spots where drifting tectonic plates pull apart from one another. Magma from below erupts and creates new crust, capped by volcanic rock that paves sea floors.
Few people have seen such generative places with poetic names like Incipient Ridge, Hess Deep and Pito Deep, where all-white eels, crabs and octopi can dwell in jet-black depths.
But on some of her 11 deep-sea research expeditions, Klein has.
“I find the descent in the dark to be an overwhelming experience,” is how Klein has described the journey two or more miles down inside mini-research submarines. “Just as you get to the bottom of the ocean, the pilot begins to turn on the lights on the outside. Suddenly you are in a magnificent world that nobody has ever seen.”
With such journeys, along with precise mapping, surveying, and lots of chemical analysis of rock, Klein sheds light, too, helping illuminate some significant physical processes on Earth.
Yes, the work is geology. But it’s also bigger, in the realm of “planetology,” says Jeffrey A. Karson, a Syracuse University earth sciences professor who also studies the ocean floor.
“When you look at the blue part of the globe, all you think about is water. In fact, there is volcanic rock underneath every part of that blue,” says Karson, a onetime Duke faculty member himself. “Emily has had a huge impact in understanding what amounts to more than two thirds of our planet.”
Klein did not envision caring about rocks when she left Los Angeles, where she grew up, to attend Barnard College. In upper Manhattan during the 1970s she had two big interests, writing and science, leaving with a degree in English and pre-med requirements under her belt.
A job in a Columbia medical school research laboratory exploring ocular physiology with animal studies opened her eyes to the power of research. She loved it all: the careful methods, the precise data collection, making discoveries, writing up and presenting the results, even composing grant applications required to start all over again.
When geology graduate students — she met a party — described where they went to conduct their research, she immediately saw that studying the Earth could be even more engaging.
“I thought to myself: they travel all over the world. They are going to the Himalayas to study mountains. They are going to California to study earthquakes. All over.” Klein recalls.
After catching up on some geology classes, Klein was admitted to Columbia University’s Lamont Doherty Earth Observatory up the Hudson River from Manhattan. Her advisor was a sea-going geochemist. “I kind of followed his footsteps,” Klein says.
It was a good time to join the fold. Not long before, geologists around the world had concurred that Earth’s crust was cracked and its pieces, the plates, moved around slowly, likely influenced by the heat of the mantle below. But lots of questions remained.
Klein became fascinated with mid-ocean ridges, volcanoes that ring Earth mostly underwater, in patterns some compare to stitching on baseballs. Most of Earth’s volcanic activity happens along these ocean crust assembly lines. Plates moving away from one another in these areas produce rifts, where magma below escapes and hardens into rock in that cold deep.
Chemical analysis of the resulting volcanic rock, the amounts and ratios of elements and isotopes within, give clues to conditions in the mantle below. “We were at a stage where we were really in the dark collecting rocks, like butterfly collecting, at different mid-ocean ridges, just describing the different rock compositions in different places,” Klein says. “There was just enough data globally in the mid 80s for the first time to start to put it all together as a whole. “
So she did. For her PhD thesis, Klein compared the chemical compositions of rocks retrieved from ridges around the world. She saw that their chemical compositions correlated with the ridge’s physical characteristics, specifically the average thickness of the crust and the depth below sea level of that ridge. And this is consistent globally, a big finding at the start of a career.
“Emily has this incredible eye for detail, a great knack for discovering things others might have missed. And she thinks about it globally,” says Terry Plank, a Columbia geochemist who trained with Klein at Lamont and studies what influences how volcanoes form on land and in the sea.
That wasn’t Klein’s only discovery that helped people better understand the big picture deep under water. Klein’s later work showed that molten rock from the mantle does not always travel vertically, as had been commonly assumed, but can in fact feed volcanoes at some distance away, complicating people’s views of where crust in one spot originates. She also has studied individual ridges in the Pacific, Atlantic and Indian oceans — to better understand variation between such places.
Chair of Earth & Ocean Sciences at the Nicholas School, Klein is well aware that such research findings don’t translate easily into breaking news headlines. But to her, their importance remains evident.
“Does it change our day to day lives? No. But it tells us how the earth works on big scales of space and time,” she says.
Klein and Ben Wernette, her graduate student, spent a month this past spring aboard the research vessel Sally Ride. With her colleague, Debbie Smith, and scientists from Spain, Russia, the United Kingdom and Poland, they mapped what’s called the Cocos-Nazca spreading center.
That stretch of seafloor is located near the equator in the Pacific, northwest of the Galapagos Islands off Ecuador. It was an alluring destination partly because successive stages of plate rifting are observable there, Klein says.
Photos posted on the expedition’s blog, “Dispatches from the Sea,” show Klein as a relaxed chief scientist in sneakers and cropped pants — sometimes a hard hat too — who creates the daily research plan with colleagues and jumps in where needed.
That included reviewing the latest “echo-sounder” mapping data, collected with an instrument that uses sound beams to calculate the shapes and sizes of structures on the ocean floor, whether they be geological faults, valleys and or volcanoes. She also supervised the deck work to collect rock samples.
“We do in the end need to get our hands on some of the rocks from the ocean floor,” Klein explains. “We do this in a truly ancient way, using a steel dredge dragged behind the ship.
The dredge has a big wire basket for collecting the rocks and is pulled by a strong wire cable that leads up to the ship. The water is usually one to three miles deep and the rocks are often tough to detach. We need to get the dredge in the right place, drag it along slowly, pull hard enough to break off some rock and then bring it back up to the ship.”
Klein, who has been at Duke for 29 years, is one of those people who step up to try to help the university continually become a better version of itself. To her, students are students first, even when they also happen to be nationally famous basketball players on Duke men’s basketball team, says Karson, who previously was on Duke’s faculty in Klein’s department.
Karson remembers a day when Klein saw a photo of Jason “Jay” Williams on the cover of a Sports Illustrated on campus. It surprised her; she knew him primarily as an undergrad, not an elite athlete. “For her, these are students who are going to learn. She’s charged with teaching them and advising them. She takes care of them like they are her own,” Karson says.
That dedication is one reason parents of students who Klein mentored gave $100,000 anonymously to create a Dr. Emily M. Klein Endowment Fund to support faculty-mentored undergraduate projects.
She engages outside the classroom too. From 2004 to 2012, Klein was faculty director of Duke’s Baldwin Scholars Program, which expanded leadership opportunities for women undergraduates on campus. She’s also chaired two Nicholas School dean search committees. After serving on the steering committee of the Faculty Diversity Task Force, intended to expand racial, ethnic, gender and LBGTQ diversity, Klein chaired its implementation committee to help ensure action items were implemented.
“Emily is a great listener; she is nonjudgmental and will take in ideas from different stakeholders, synthesize them and propose ways forward,” Provost Sally Kornbluth says of Klein, a friend since two of their now-grown kids became best friends in kindergarten in Durham. “She is always willing to roll up her sleeves and work hard, even when she won’t get any direct credit for the work.”
For those and many more reasons, Duke’s Board of Trustees recently named Klein a University Distinguished Service Professor of Earth Sciences. Distinguished professorships are the highest honor Duke bestows on its faculty.
Klein shows no signs of slowing down. A few weeks after returning from the Pacific cruise, she was back in her longtime lab in Old Chemistry Building on the West Campus quad showing Wernette, her PhD student, how to melt ground-up volcanic rock in a small furnace. Not a typical furnace, her device heats up to 2100 degrees Fahrenheit.
Lots of careful work goes into properly melting the basalt rock Klein brings back from deep sea. First, she and members of her lab must chip a glass “rind” off the rock with a chisel. Then they break the glass chunks into extremely small chips, using a sieve to retrieve pieces about the size of the heads of pins. Those fragments get dried in an oven overnight.
Next the mini-fragments get washed in distilled water and carefully sorted, so that any chemically altered rock can be removed, work that requires hours of sorting aided by a microscope. What’s saved gets ground into a very fine powder that is heated in the lab furnace twice, once alone and later, at 1200 degrees Celsius, mixed with a flux powder that lowers its melting temperature.
The preparation allows Klein’s spectrometers to measure the chemical composition of the rock in minute quantities as low as parts per billion. Specifically, she looks for 50 major elements (silica, iron, magnesium and aluminum included) and trace elements (such as vanadium, copper, chromium, rare earth elements, uranium, lead) within.
The contents will make clearer how a newly forming mid-ocean ridge got started and changes over time, Klein says. It no doubt will point the way to new research questions.
Getting molten rock out of the inferno in red-hot graphite containers called crucibles for the last step is tricky, Klein warned Wernette, and requires unwavering concentration Before handing protective gloves and a pair of tough tongs to her student, Klein’s message was simple.
“Don’t fret. If something flares up just carefully put it down. All it is, is a stupid sample,” she says soothingly. In other words: You’ve got this. There is always time to do things right. And it’s always worth doing it right. As Klein knows, very big things can come from even tiny samples.
Catherine Clabby is a journalist who writes about science and the environment. She lives in Durham, N.C. Photography by Dominik Zawadzki, Iker Blasco del Barrio, Charlie Dunham, Gaby Alodia and Scott Curry.
The Sally Ride Expedition: Emily Klein and Ben Wernette, her graduate student, spent a month this past spring aboard the U.S. research ship Sally Ride. With scientists from Spain, Russia, the United Kingdom and Poland, they mapped what’s called the Cocos-Nazca spreading center. That stretch of seafloor is located near the equator in the Pacific, northwest of the Galapagos Islands off Ecuador. View at blogs.nicholas.duke.edu/cocosnazca/.