Educator goes searching for Earth’s secrets beneath sea floor
Vicki Jackson | Gazette correspondent
Published: October 30, 2013   |
Updated: October 30, 2013 at 04:04 PM
A sea-faring expedition aboard the JOIDES Resolution was a unique thrill in the life of Teresa Greely, science educator and biological oceanographer with the University of South Florida.
She shared some of the wonders of that voyage in her presentation on Oct. 17 as part of Clearwater Marine Aquarium’s Making Waves speaker series.
With research experience in extreme environments like the Arctic and in submersibles, Greely spent the first half of her career studying fish. She now communicates her love of the ocean by teaching college courses in marine science, biology and fish ecology — and also enjoys exploring with a purpose. In addition, every summer she participates in an oceanology camp for girls.
She was selected to join, as education officer, the 2012 expedition of an international team of specialized scientists, including geologists, volcanologists and chemists. Onboard the research ship JOIDES Resolution, she used the Skype software application to interact with classrooms of budding scientists all over the world, allowing them to experience the adventure in real time.
On the giant drillship mounted with a derrick, the crew sailed from Puerto Rico to explore volcanoes off the Caribbean islands, Montserrat in particular. The area is prone to volcanic eruptions and earthquakes. The oceanic study supplemented land-based information to form a more complete picture of volcanic processes. In addition, the locale allowed deep exploration relatively near land, at 25 to 40 miles offshore.
Funded by the National Science Foundation and jointly owned by 30 countries, the ship is designed to discover the secrets hidden in the depths of Earth’s oceans. A giant drill operates around the clock from the 470-foot-long deck of the Resolution via access through a moon pool, an opening 23 feet wide. Core samples are collected from miles below the sea floor, where the pressure and cold of the deep water allow preservation of buried clues to the history of the planet.
Multiple samples, each approximately 10 meters long, are extracted and cut into shorter pieces, which are then split in half vertically. One half is encased to be archived, while the other is subjected to extensive study, which includes carbon dating and magnetic resonance imaging.
Greely explained that the specimen cavities are filled with sediment containing marine bivalves, gastropods, algae and foram. The preserved shells of the latter, a microfossil, are especially indicative and serve rather “like the canary in a mine shaft,” Greely said. Easily influenced by pH, oxygen and temperature, they’re good indicators of historical environmental changes.
“Core samples help scientists study interesting and important questions,” she said.
For example, they might address the history of climate change; the cause of the extinction of dinosaurs and other animals; the impact of volcanic eruptions; and the effect of plate tectonics, the phenomena of continental drift, on the ocean floor.
“The Earth is literally moving under our feet,” Greely said. “There are hundreds of volcanoes every day on the ocean floor. The largest mountain ranges are underwater.”
What’s more, the Atlantic Ocean is getting bigger, while the Pacific is getting smaller, she said.
“If it weren’t for education, we’d all be at a loss,” surmised the teacher. As scientists have been studying the ocean only for about a hundred years, “there’s still a lot to know.”
More information about past or future expeditions is available at joidesresolution.org.
The speaker series continues Nov. 21 with Michael Walsh, a clinical associate professor and co-director of aquatic animal health with the University of Florida’s College of Veterinary Medicine.
Because of the filming of the movie “Dolphin Tale 2” at the aquarium’s Island Estates facility, the free talk again will be at Winter’s Dolphin Tale Adventure, 300 Cleveland St. at Osceola Avenue in downtown Clearwater. The evening will begin at 6 p.m. with complimentary refreshments, and the public is invited.