Norfolk's underwater forest: More secret gems revealed Published duration 22 August 2015

image copyright Rob Spray image caption Dawn Watson swimming by a Victorian anchor found on a previous visit

Divers exploring a 10,000-year-old submerged forest off the Norfolk coast say a shift in the seabed has exposed much more of the hidden treasure.

The prehistoric forest was first discovered when thousands of tonnes of sand moved after the 2013 storm surge.

But now a further dive by Dawn Watson and Rob Spray 30m (100ft) off the coast has uncovered remarkable new sights.

Despite believing the forest would have been hidden again by sea, they found a new "thick, black floor."

The forest of "knocked flat" trees is said to be originally part of " Doggerland " which connected Great Britain to Europe after the last Ice Age.

image copyright Rob Spray image caption A veneer of mobile sand covers the "blackened wood"

image copyright Rob Spray image caption A host of sealife has descended on the "thick, black floor" wood since the shift in the seabed

The couple, from Seasearch, were diving to about 9m (30ft) down off the Norfolk coast, out from Cley, when they made the discovery.

Mr Spray said: "They say there's a veneer of sand down there, but the word 'veneer' really doesn't do it justice.

"We dived and came across an area where it looked as if the sea bed was black. If you had a big broom it looked as if you could have swept it away, to reveal a flat black floor under thick sand.

"You get the impression it might stretch for tens of metres, but you could only see for five to six metres anyway.

"It was a lovely surprise but it's very hard to get a complete scope or handle on it."

image copyright Rob Spray image caption Dawn Watson on the most recent dive, which revealed the latest find about 30ft down

image copyright Rob Spray image caption The Victorian anchor is covered in fanworms and anemones

Ms Watson first found the submerged forest bed, and then a Victorian anchor lying on top of it, which they had discovered on a previous visit.

They then saw the new section of of bed recently uncovered by the sea. She said thousands of sea animals had swarmed in on it, creating excellent photographic opportunities.

Mr Watson said: "We came to it from an odd angle, it would have been easy to miss it.

"We really would have assumed that it would have been covered over again."

The forest was originally discovered last year by Ms Watson, who described to the BBC Inside Out programme how they had come across "an enormous wave of black stuff".

Later she realised it was the remains of a forest, probably of oak trees, that had been knocked flat.

After the new find, the couple hope to continue their search of the area with further dives.

Mr Spray said: "We'll continue to survey the prehistoric forest bed but, as amateurs, resources are always limited.

"But it's a fine example of how citizen scientists often lead the way where ever-shrinking government resources may never reach."

Inhabitants of Doggerland were thought to have abandoned it after several thousand years of constant flooding.

Remaining tribes living there were wiped out by a catastrophic five-metre tsunami about 8,200 years ago.