Unexpected Geological Structures Discovered Beneath the North Sea Could Impact Carbon Storage
A team of researchers from Norway and the UK has unearthed a surprising geological phenomenon beneath the North Sea: massive sand bodies that have seemingly sunk into the ocean’s crust, while older sediment layers rose to take their place. These structures, dubbed “sinkites,” represent a previously unknown type of stratigraphic inversion and could have significant consequences for ongoing and future carbon capture and storage initiatives.
“This discovery reveals a geological process operating on a scale we’ve never observed before,” explains Mads Huuse,a geologist at the University of Manchester. “We’ve identified substantial structures where dense sand has descended into lighter sediments, effectively reversing the typical layering of rock and creating enormous mounds under the seabed.”
The research, detailed in a recent publication in Communications Earth and Surroundings, utilized a combination of direct rock samples and advanced 3D imaging to analyze these formations. The sinkites are described as extensive mounds and ridges of sand, embedded within finer-grained sediments, reaching heights of several hundred meters and stretching for tens of kilometers.
Scientists believe these sinkites formed between 10.4 and 1.6 million years ago, during the Late Miocene and Pliocene epochs. Earthquakes or shifts in subterranean pressure likely triggered the process, causing the sand to liquefy and flow downwards through fractures in the seafloor. This downward movement displaced existing layers of sediment, known as “ooze rafts” or ”floatites” – rigid, porous layers rich in microscopic marine fossils. these lighter rafts than ascended to the surface of the sand mounds,inverting the natural geological order.
“This research highlights the unexpected ways fluids and sediments can move within the Earth’s crust,” Huuse notes.”Understanding the formation of sinkites is crucial for accurately assessing underground reservoirs, ensuring effective sealing, and predicting fluid migration – all critical factors for successful carbon capture and storage.”
The discovery holds particular relevance as the world increasingly focuses on carbon capture and storage as a key strategy to combat climate change. With projects like the recently launched commercial carbon storage facility in norway beginning to pump CO2 into the North Sea seabed, understanding the underlying geological complexities is paramount. The presence of sinkites could influence the safety and effectiveness of these storage sites, as well as impact predictions regarding the location of existing oil and gas reserves.
While the findings have sparked debate within the scientific community, Huuse remains optimistic.”As with any new scientific model,there are both supporters and skeptics. Further research and time will be needed to determine the widespread applicability of this model.”
