Researchers have learned that the site responsible for more than 75 percent of the world’s volcanic activity is more active than previously thought as they recently discovered five new hydrothermal vents, each spewing fluids hotter than 570°F.
The vents spew liquids that are hotter than 570°F and are the result of the ongoing splitting of the tectonic plates of the East Pacific Rise.
The use of a robotic underwater vehicle and a manned submersible sped up the discovery. A team led by Jill McDermott of Lehigh University dove to a depth of 1.6 miles in the eastern Pacific Ocean using both the Sentry autonomous underwater vehicle and the Alvin human-operated submersible (both operated by the Woods Hole Oceanographic Institution’s National Deep Sea Diving Center). The vehicles were used to track one of the most active thermal spots known on the East Pacific Rise, near 10° north latitude, according to Popular Mechanics.
East Pacific Rise. kp.ru
“It’s dotted with thousands of these deep-sea hot springs, which collectively extract 10 percent of the Earth’s total internal heat,” Thibault Barreve, one of the expedition’s leaders, said in a statement. “We want to expand our understanding of how hydrothermal vents release heat and chemicals as they travel along the seafloor and impact the world’s oceans.”
The discovery of these hotter springs was the result of a collaboration between humans and the robot Alvin. Each night, the team sent out the Sentry robot to scan high-resolution maps using its sensors. When the robot was returned in the morning, the researchers planned how to use the human-occupied Alvin to better explore areas that might prove valuable.
“Sentry’s high-resolution maps allow us to detect potential new hydrothermal fields soon after Sentry returns to the deck,” McDermott said in a statement. “This gives us excellent targets for Alvin and the ability to make multiple discoveries in a single dive.”
The East Pacific Rise — part of the globe’s mid-ocean ridge volcanic mountain chain — has two tectonic plates that are moving apart at a rate of more than 4 inches a year, making it a prime location for research. But getting Alvin’s data there was a key part of the equation. Alvin has proven its importance in detecting hydrothermal vents since it first began exploring the ocean spreading ridge north of the Galapagos Islands in 1977.
The researchers say that because chemical-rich vents provide energy for animal life and create a diverse ecosystem in the waters around the vents, a better understanding of these underwater vents could give researchers key tools to search for potential life-supporting environments throughout the universe.
Daniel Fornari, one of the expedition’s lead scientists from the Woods Hole Oceanographic Institution, said Sentry’s mapping provides important details about the lava flows that erupt in the deep ocean, allowing them to target ideal locations to collect rock samples. “These new perspectives and rock sample analysis will allow us to determine how fast the lava erupted, how far it traveled, and what impact deep-sea lava eruptions have on hydrothermal vents,” he said in a statement.
A follow-up expedition aims to detect clearer geophysical, chemical and biological processes. It could reveal even more hydrothermal emissions from one of the most intense volcanic sites on Earth.
