Mar 09,2007 00:00
NEWPORT – A team of
Their preliminary findings suggest that this remote region in the
“This is a small subduction zone that supposedly has ceased its tectonic activity, but we recorded an awful lot of earthquakes during the expedition,” said Robert Dziak, an
“But what we are able to learn from the deployment of these hydrophones suggests that this is truly a unique area that deserves a lot more research,” Dziak added.
The project is a component of the National Oceanic and Atmospheric Administration’s (NOAA) Ocean Explorer program. In December of 2005, the researchers deployed several hydrophones – built by OSU technicians at the
What they have found thus far in analyzing the data is a symphony of sounds revealing undersea earthquakes, the movement of massive icebergs, and the vocalizations of whales, penguins, elephant seals and other marine mammal species.
The scientists were particularly intrigued by the humming sounds recorded from the movement of icebergs following the earthquakes. Icebergs that are grounded on the seafloor often get slowly pushed by currents and wind, causing them to vibrate like a tuning fork and make a loud hum.
“With the big Antarctic ice sheets, you can pick up the hum they make as far away as
This relationship between earthquakes and ice fields is a new idea and unique to the region, Dziak pointed out.
“This is the only place at either pole where large earthquakes occur in proximity to ice sheets,” he said. “In fact, while our instruments were deployed here, a magnitude 7.5 quake hit the region, generating a small tsunami. It’s a very active area.”
This region of the Antarctic is near the
Though their research is primarily designed to study the seismic activity of the region through the use of hydrophones, the scientists also used a remotely operated vehicle to explore the comparatively shallow waters of
“There was a real sense of accomplishment in even being able to conduct our deep-water survey in this incredibly hostile environment,” Dziak said. “We got somewhat lucky with the weather.”
In addition to the sounds of earthquakes and moving icebergs, the hydrophones picked up the sounds of numerous marine mammals and birds. Kate Stafford, a
Whales have unique “voices” that can not only be differentiated by species, the researchers say, but by geographic dialect. In other words, blue whales from one part of the world have a different “accent” than blue whales from the other side of the globe.The researchers’ activities were documented by Bill Hanshumaker, an outreach specialist at the