An international team of scientists unveiled exceptionally well-preserved glacial landforms buried nearly one kilometer beneath the North Sea, dating back approximately one million years.
Researchers utilized 3D seismic technology, originally developed for assessing sediment suitability for oil, gas, and renewable energy infrastructure, to uncover these ancient features. The technology revealed a landscape shaped by a vast ice sheet that once extended from Norway toward the British Isles. The seismic data also uncovered elongated furrows incised into the former seabed by powerful ocean currents predating the ice sheet's advance, indicating a dynamic marine environment.
Dr. Christine Batchelor, a senior lecturer in physical geography at Newcastle University, emphasized the importance of studying how past glaciers reacted to long-term climate changes. Lead author Dr. Dag Ottesen from the Geological Survey of Norway noted that the high-resolution data allows for detailed examination of the landscapes buried under the North Sea sediment.
The research team identified glacial landforms, including streamlined ridges carved by ice movement and features marking the ice sheet's retreat. They found that strong ocean currents dominated the North Sea region before ice sheets took hold around one million years ago, shaping the seabed and creating elongated furrows.
Modern seismic data suggest that ice sheets in northwest Europe expanded significantly in response to climate cooling about one million years ago, aligning with the Mid-Pleistocene Transition, a period that reshaped global climate patterns.
Understanding the response of past ice sheets to climatic shifts can improve predictions regarding today's ice sheets and climate warming. Dr. Batchelor stated that the next step involves acquiring long sediment cores to better understand the timing of glacial events. The study acknowledges a limitation due to the lack of data about the precise age of the landforms.
Dr. Ottesen remarked that these results significantly alter existing ideas about the glacial history of the North Sea. Identifying ancient glacial landforms has historically been challenging due to their burial under thick sediment layers.
Other co-authors include Helge Løseth at Equinor ASA and Harald Brunstad at Aker BP ASA. The findings were published in the journal Science Advances.