Woods Hole Researchers Studying Hydrothermal Vents On The Floor Of Yellowstone Lake

Yellowstone Lake, on its surface, is an immense body of deep, cold water that could be fatal in a matter of minutes to anyone who fell into it. But deep down, on the lakebed, hundreds of hydrothermal vents are furnace-like, generating water temperatures of more than 300 degrees in some parts of the lake. Beyond the astonishing temperatures, though, researchers from the Woods Hole Oceanographic Institution hope their studies help them answer how "environmental processes and climate affect continental hydrothermal systems."

There is more, of course, expected to be teased out from the three field seasons the researchers are to spend on the lake. What microbial habitats might be clustered around these vents? How do earthquakes impact the hydrothermal vents, of which there are an estimated 250 on the lakebed. What triggers hydrothermal explosions?

"The project is sited in the northern half of Yellowstone Lake, which hosts one of three major thermal basins in Yellowstone National Park," the project's website notes. "While most of the thermal activity in Yellowstone discharges into pools, fumaroles, and geysers that can be observed on the ground surface, the system beneath the lake discharges through a series of vents and fissures onto the lake floor, where it is hidden from sight. This thermal system is particularly sensitive to perturbations, making it an ideal location for studying the cause-and-effect relationships between magmatic, tectonic, and environmental activity with hydrothermal circulation. The extreme sensitivity of the system to perturbations is evidenced by the fact that the northern part of Yellowstone Lake hosts the largest known hydrothermal explosion craters in the world, which are generated when the pore pressure in a system suddenly drops, causing catastrophic vapor explosions that can excavate large volumes of rock and fluid."

Along with measuring vent temperatures and studying water flows, the research also involves taking core samples from the lakebed to study sediments that might tell stories of the environment before and after hydrothermal explosions.

"Even though all of the sites are within Yellowstone Lake, each one is in a different geologic area, including a deep ‘graben’ (a ditch in between two faults), a large hydrothermal explosion crater, the deep, hydrothermally active hole east of Stevenson Island, and areas of landslide deposits. The cores from these different sites will give the team an unprecedented look at the post-glacial geological history of the lake region, including the processes by which large hydrothermal explosion craters were formed," Chris Linder, one of the researchers, wrote on the project's blog.

"Several cores were 40 feet in length (previous cores from the Lake maxed out at ~28 feet), and one of the cores may have penetrated into glacial flour, meaning it may provide a complete record back to the last glaciation. Many of the cores contained significant amounts of gas, probably carbon dioxide, especially the Stevenson Island core. The team is thrilled with the coring effort and eager to see what stories the cores will reveal."

The core samples are scheduled to be opened in January.