Indiana State students help probe Alaska mysteries

Landlocked Midwesterners study effects of tsunami on undersea life

By Dave Taylor

ISU Communications & Marketing

When college students study samples under a microscope, they’re often looking at stock slides someone else collected long ago. But some Indiana State University students are spending the fall semester examining samples they collected themselves just last summer.

       The samples came from an unexplored region of the sea floor in the Gulf of Alaska below one of the world’s most important fisheries, where an Indiana State professor led a research cruise investigating possible causes of one of the most devastating tsunamis in United States history.

      The voyage has uncovered new mysteries about biological and geological processes off the Aleutian Islands along the northern part of the Pacific Rim.

            In addition to identifying previously undiscovered deep-sea habitats, the researchers have stirred debate about the causes and characteristics of a 1946 tsunami that killed at least 165 people, most of them thousands of miles away in Hawaii.

            Scientists had indicated the tsunami originated with an undersea landslide but detailed mapping of the region “showed no large displacement of the predicted magnitude,” said Tony Rathburn, assistant professor of geology at Indiana State.

            Rathburn used the word “startling” to describe the findings. “Tsunami modelers now have to go back and scratch their heads a little bit to try to come up with a different scenario that will account for the size and the timing of the tsunami,” he said.

            Researchers also found previously undiscovered methane seeps and deep sea coral habitat, some possibly associated with the methane seeps.

“These were like coral gardens at 3,000 meters beneath the surface of the ocean – just beautiful scenery of corals, many of which are probably over 100 years old,” said Rathburn, chief scientist on the cruise that included researchers from the universities of Alaska, Hawaii, Florida and Oregon and the Scripps Institution of Oceanography at the University of California, San Diego.

            Though researchers focused on worms, crustaceans and single-celled creatures, they also found clams and other animals that obtain nutrition from chemical discharges in the methane seeps, a process known as chemosynthesis.

            The project involved extensive mapping of the area using the ship’s multi-beam sonar technology and the collection of sediment samples using the Woods Hole Oceanographic Institution’s Jason II remotely operated vehicle, similar to the vehicle made famous by the movie Titanic. An undersea camera towed by the ship also helped to provide detailed images of the seafloor and a census of larger seafloor dwelling creatures. The technology allowed researchers to chart new canyons and features of a previously unexplored, remote region.

            The National Oceanic and Atmospheric Administration’s West Coast National Undersea Research Program sponsored the cruise, aboard the Scripps research vessel Roger Revelle.

            NOAA funding paid for two Indiana State students and an ISU postdoctoral researcher to participate in the cruise. Rathburn secured additional monies from ISU’s experiential learning grant funds to enable two other students to take part. Three of the four ISU students participating in the cruise were undergraduates.

            “It makes a huge amount of difference” to actually take part in such an expedition, rather than merely examine samples someone else brought back, said Brian Wrightsman of Terre Haute, a senior geology and science education major.

            “You get to see first hand how these things are done, how the samples that you look at are collected and how research is actually conducted in the field. Plus, it’s significantly interesting that here in Indiana we have the opportunity to do oceanographic research in a landlocked area,” Wrightsman said.

            “I got to see the different interactions that scientists have in real world experiences,” said senior geology major Jessica Adamic of North Branch, Mich. “You have to be very willing to give any of your information to others and to benefit everybody as a team.”

            Adamic chose to attend Indiana State because of the reputation of its department of geography, geology and anthropology.

“I knew …  I was going to be given a one-on-one experience with any professor, I was going to be given awesome opportunities for research. I was doing research as a freshman and I was presenting at conferences as a sophomore and I know at a lot of other universities that’s something you don’t do as an undergrad all,” she said.

            It was that hands-on experience for students that set the cruise apart, said Rathburn.

            “They were helping to deploy and recover instruments, processing samples at sea, and recording notes and observations of the seafloor work. They weren’t just passengers. They worked side-by-side with well-known scientists. They got very little sleep and worked long hours. This was a 24-hour-a-day operation,” he said.

            “We slept randomly throughout the cruise,” said Michelle Abriani, a senior geology major from Greencastle. Abriani served on the deployment and recovery team for Jason II and monitored the images transmitted by the remote camera. “Even though it was 4 a.m., I was happy to get the experience,” she said.

            “It was definitely worth it. This cruise reaffirmed my career choice, to obtain a PhD and work as a paleo-oceanographer,” said Amanda Bahls, a second-year graduate student from Perrysville.

            Rathburn is looking forward to a return trip with students to the Gulf of Alaska.

            “We’re really intrigued by what we saw, by what we were able to sample and we’re already planning to go back with a new set of questions,” he said.

Note: Photos and video for this story are available by contacting ISU Communications & Marketing at (812) 237-3743