Skydiving. Road trip across the United States. Climb Pike’s Peak. Everyone has a bucket list item.
And over the next month, on a ship in the Pacific Ocean, Mahomet resident Professor Craig Lundstrom will mark off his lifelong dream of taking a submarine to the East Pacific Rise to study volcanic activity along the ocean floor..
“This is a bucket list things for me because when I did my Ph.D., it was all about volcanism on the ocean floor,” Lundstrom said. “I never got on a cruise; never went down to collect samples myself. It was all stuff other people picked up for us. From that standpoint, this is kind of cool for me.”
The expedition, which will begin on Tuesday, has two purposes. First, the group of 17 scientists including Principle Investigator Trish Gregg (Assistant Professor of Geology at UIUC) will map a seamount chain that strings to the west of the East Pacific Rise for the first time.
“What we have right now are pretty good maps along the mid-ocean ridge because that’s something that scientists want to know about and they study, but as soon as you get off the mid-ocean ridge and you’re into the abyssal plains, there is a lot of ocean floor that is not mapped,” Lundstrom said.
From satellite imagery, scientists can see an outline of a seamount chain but know little else about it. By “mowing the lawn,” meaning taking the 270-foot research vessel Atlantis back and forth across this area of ocean, scientists will use sonar to make bathymetry maps of the area.
Second, the expedition will also collect rocks from the seamounts to test their hypothesis that the compositions of lavas change with distance from the East Pacific Rise. Sample collection will use the submersible “Alvin.” They will use the “arms” of the submarine to collect rock samples from different areas. Through these samples, the scientists will be able to analyze the activity, age, composition and the function of the volcanoes.
“Based on what we can see, we think there has been volcanism along the entire chain continuously,” Lundstrom said. “We don’t know this for sure, but from the already mapped volcanoes close to the ridge the lava flows look young and fresh. Essentially you’re using sonar to see the surface and if it’s very shiny to sonar it means it’s fresh; and if it’s not, that means it has a lot of sediment on it.”
“So we think that this is a chain of volcanoes that is continuously producing lava– that would be good for us because it says the seamount chain passively samples the mantle system, and if so, we’re seeing the entire melting area underneath the ridge,” he continued.
“This is a part of the complete discovery aspect of this,” he said.
While Lundstrom said it is pretty unlikely, he dreams of seeing an active volcano erupt or finding a caldera, a large volcanic crater where scientist could sample the vertical layers of the volcano.
More likely, Lundstrom believes they might find a hydrothermal system where ocean water circulates into hot rock below, then spews out hot black mineral deposits into the water.
With 25 submarine trips to the volcanos and 17 scientists, Lundstrom is only scheduled to go on the Alvin one time. In a small space, facing the window on the submarine, the lights will be turned off while the group descends for two hours in the dark. Once they reach their destination, they will map the seamount volcano for three hours before they ascend back to their ship for another two hours.
On days when he is not on the submarine, Lundstrom will be part of the scientific crew that will check to make sure all of the data is being collected. When rock samples come back from the expeditions, the group will cut the rocks open, work on first characterization, clean the rocks up and disperse them among the scientists on the cruise.
Lundstrom and Gregg will then bring their samples back to the University of Illinois to study the compositional and isotopic properties alongside graduate students to test their hypothesis that the composition of the matter will change along the progression of the seamount chain.
The second part of this expedition is to bring the world right into the science classroom by producing YouTube videos that students (and the public) can watch a couple times a week.
“We need to get people, especially school-aged kids, interested and making (the YouTube channel) a popular, high-hit site. Ultimately this is all taxpayer funded. When you write a proposal, you have to say this is what I will do scientifically, but you also get rated equally on these things called broader impacts, your outreach efforts.”
Lundstrom visited Mahomet-Seymour Junior High School last week to help students get interested in the expedition and to prepare them for the videos that will be shared in their classrooms over the upcoming weeks.
Lundstrom said because the Earth is covered in 71% of water, scientists may never have great maps of the whole ocean floor. But technological advances are helping scientists map underwater more precisely than they ever have before.
When Marine Biologists mapped the mid-ocean ridge 20 to 30 years ago, they could only map variations at the 10 meter level. But not, those variations are being mapped down to a few meters.
Lundstrom also said technological advances in the last 15 years in the Geochemistry field will make this expedition even more satisfying than it may have been while he was in college.
“We now have a mass spectrometer, which can measure isotope ratio for things we were never able to measure 15 years ago,” he said. “We’ve learned that you can see these isotope fractionations and isotope ratio changes that have to do with thermal gradients. So this is a perfect study for what I do. We can predict that we might find isotopic signatures of temperature gradients in the mantle.”
