
What was once a man-sized sinkhole on the coast in northern England has grown larger year after year. It now is approximately 40 feet wide and poses a hazard for people visiting the beach.
The National Trust, A UK conservation charity that manages the cliff path around the sinkhole, recently took steps to warn people of the danger.
“We have put up fencing and warning signs around this sinkhole, which is away from the main path running along the cliff tops of The Leas and Whitburn Coastal Park, known locally as The Wherry,” National Trust said in a statement, a Daily Mail article reports. “There are warning signs at key points along the cliff edges, as well as visitor information panels in each car park. We’d urge people to take a moment to look at these signs, and to stick to the main paths to keep themselves, their children, and their dogs safe.”
A Small Beginning
The massive sinkhole — which can be seen in the video below — first appeared as a small sinkhole at Whitburn, near Sunderland, in 2003. Each year since then, it has grown larger, and in the process, came to be known as “Souter Hole.”
The sinkhole now is so large and deep that it contains a hidden beach. The sea even forces its way into the sinkhole through a crack in the cliff walls, resulting in “waves” that wash across the sinkhole’s beach.
“It’s growing into a huge beast, adding even more drama to the rugged coastline,” local beach artist Clair Eason said in the Daily Mail article.
How Sinkholes Grow
Giant sinkholes, technically known as “dolines,” are generally formed as seawater forces its way through a fault, or crack, in limestone cliffs. In the Daily Mail article, Dr. Vanessa Banks, the British Geological Survey’s Shallow Geohazards and Risks team leader, said that dolines are common in coastal areas such as Whitburn.
“Dolines are often formed where you have cold water and glacial sand and gravel deposits underlain by soluble rocks such as dolomitized limestone or gypsum,” Dr. Banks told MailOnline, the Daily Mail reports. “These processes may have started toward the end of the last glaciation. Once a void has formed, it will enlarge due to stress relief at its sides and from below as sea water moves sediment during high tide.”
The Beauty Of Nature
The National Trust notes that the Sunderland sinkhole is surveyed regularly, but there really isn’t much that can be done about it.
“By its nature the coastline is constantly changing, with some areas particularly prone to erosion and landslips,” a spokesperson told the Daily Mail. The National Trust has put up fencing and warning signs because “We want all of our visitors to have an enjoyable, relaxed, and safe visit to Whitburn Coastal Park.”
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