Perhaps counterintuitively, sediment layers usually tend to stay intact on the seafloor than on land, to allow them to present a greater report of the area’s historical past. The seafloor is a extra secure, oxygen-poor atmosphere, lowering erosion and decomposition (two causes scientists discover way more fossils of marine creatures than land dwellers) and preserving finer particulars.
Samples from completely different areas range dramatically in time protection, going again solely to 2008 for some and again probably greater than 15,000 years for others as a consequence of wildly completely different sedimentation charges. Scientists will use strategies like radiocarbon relationship to find out the ages of sediment layers within the core samples.
Microscopic evaluation of the sediment cores may even assist the workforce analyze the way in which the eruption affected marine creatures and the chemistry of the seafloor.
“There’s all kinds of life and sediment sorts discovered on the completely different websites we surveyed,” mentioned Alastair Hodgetts, a bodily volcanologist and geologist on the University of Edinburgh, who participated within the expedition. “The oldest place we visited—an space scarred by historical glacier motion—is a fossilized seascape that was utterly surprising.”
This function, too, tells scientists about the way in which the water strikes. Currents flowing over an space that was eroded way back by a glacier sweep sediment away, holding the traditional terrain seen.
“I’m very fascinated with analyzing seismic knowledge and correlating it with the layers of sediment within the core samples to create a timeline of geological occasions within the space,” mentioned Giulia Matilde Ferrante, a geophysicist at Italy’s National Institute of Oceanography and Applied Geophysics, who co-led the expedition. “Reconstructing the previous on this approach will assist us higher perceive the sediment historical past and panorama adjustments within the area.”
The workforce has already gathered measurements of the quantity of sediment the eruption delivered to the ocean. Now they’ll work to find out whether or not older layers of sediment report earlier, unknown occasions much like the 2008 eruption.
“Better understanding previous volcanic occasions, revealing issues like how distant an eruption reached, and the way widespread, extreme, and predictable eruptions are, will assist to plan for future occasions and scale back the impacts they’ve on native communities,” Watt mentioned.
Ashley writes about area for a contractor for NASA’s Goddard Space Flight Center by day and freelances as an environmental author. She holds grasp’s levels in area research from The University of North Dakota and science writing from The Johns Hopkins University. She writes most of her articles with a child on her lap.