Exploring an undersea terrain sculpted by glaciers and volcanoes

Perhaps counterintuitively, sedimentary layers on the ocean floor are more likely to remain intact than on land, so they can better record the history of the area. The seafloor is a more stable, anoxic environment that reduces erosion and decomposition (two reasons why scientists find far more fossils of marine life than land life) and preserves finer detail.

Samples from different regions vary widely in time frame, with some dating back as far as 2008 while others may go back more than 15,000 years due to widely varying sedimentation rates. Scientists will use techniques such as radiocarbon dating to determine the age of the sediment layers in the core samples.

Microscopic analysis of the sediment core will also help the team analyze the impact of volcanic eruptions on marine life and seafloor chemistry.

“We found a wide variety of life and sediment types at the different sites we surveyed,” said Alastair Hodgetts, a physical volcanologist and geologist at the University of Edinburgh who participated in the expedition . “The oldest place we visited – an area scarred by ancient glacial movements – was a completely unexpected fossilized seascape.”

This feature also allows scientists to understand how water moves. Water flowing through areas eroded by glaciers long ago sweeps away sediment, leaving ancient terrain visible.

“I’m interested in analyzing seismic data and correlating them with sedimentary layers in core samples,” said geophysicist Giulia Matilde Ferrante of Italy’s National Institute of Oceanography and Applied Geophysics. “Reconstructing the past in this way will help us better understand the region’s sedimentary history and landscape changes. “

The team has collected measurements of the amount of sediment flowed into the ocean by volcanic eruptions. Now, they will work to determine whether older sedimentary layers record an earlier, unknown event similar to the 2008 eruption.

“Better understanding of past volcanic events, revealing the extent of volcanic eruptions, how common, severe and predictable they are will help plan for future volcanic events and reduce their impact on local communities,” Watt said. Community impact.

Ashley writes about space by day for contractors at NASA’s Goddard Space Flight Center and works as a freelance environmental writer. She holds an M.A. in Space Studies from the University of North Dakota and an M.A. in Science Writing from Johns Hopkins University. She wrote most of her articles with a baby on her lap.