Ancient stories to be read in the rocks beneath our feet

Carboniferous landscape
Blanchland, approximately 300 million years before the arrival of the White Monks

Many keen gardeners in Blanchland and the surrounding area will have dug up pieces of sandstone containing odd indentations, a bit like the impressions of chunky mountain bike tyres running over recently laid concrete. Or sharp-eyed walkers might have spotted these bits of patterned rock in paths, stone walls or beside the river.

Needless to say, mountain bikes were still over 300 million years off when these fossils were formed in the swampy tropical rainforests of equatorial Upper Derwent! They are the fossilised spiny roots of Sigillaria or Lepidodendron, tree-like plants which grew around 30 metres tall in the vast tropical forest that once cloaked the entire North East. When the trees died their remains were buried by sand from nearby rivers. Over time, the sand hardened to sandstone, preserving roots, bark and even leaves.

This ancient forest would have been very different from modern rainforests. Dragonflies the size of kestrels flitted through the trees, and giant scorpions and cockroaches scuttled through the undergrowth. Large amphibians lived beside the many rivers which flowed through the forest. There were no birds or mammals - they had yet to evolve, and even the first dinosaur would not appear for another 100 million years!

You can get an idea of just how long ago these ancient swamp forests covered the area if you imagine the whole of the time modern humans have walked the Earth - that's around 200,000 years - as represented by one minute. Using the same timescale, the equatorial forests of the Derwent Valley were flourishing about this time yesterday!

Much has happened since; the land mass containing the British Isles drifted northwards through different climatic zones to its current position. Millions of years of erosion, including the effects of many ice ages, have exposed the rocks we see today.

The Stanhope fossil tree is a well-known local example of these huge, long-extinct trees. This is the species Sigillaria, which is an early ancestor of clubmosses. Today, these are small mountain plants which grow in rocky parts of the North Pennines.

Found in a quarry at Edmundbyers Cross in 1915, the Stanhope tree is one of several found in the same area which were taken to various places for preservation. Stanhope's fossil was taken in large pieces to the town in the early 1960s and reassembled in the churchyard.

But there's a record of several spectacular fossils discovered deep in the Ramshaw lead mines more than 150 years ago that, had they survived the London Lead Company's determined tunnelling, would possibly have been one of the best examples of a fossil grove in Britain. Whellans' directory of 1856 records the amazing find of a group of fossil trees...

"About 300 feet from the surface in driving a waggate drift in the vein, the miners came to a number of trees, seven in all, the largest of which was about six feet in circumference, their branches and leaves were of necessity cut out to prosecute further working of the mine. A part of one of the trees is still standing in the mine, guarded with rails to preserve it as a memento of the discovery. This account is taken verbatim from John Robinson Esq, who was mining agent here for about 46 years, a situation which he very recently retired."

Perhaps the remaining tree trunk is down there to this day, minus its leaves and branches, but with iron railings lying rusted and broken around its base.

Meanwhile, back above ground, Dr Elizabeth Pickett, a geologist with the North Pennines AONB Partnership and a resident of Blanchland, says there are lots of fantastic fossils to be seen when walking around the area:

"Have a look at some of the large stone blocks around the White Monk Tearoom - one has traces of ancient roots running across its top surface. Stone walls are also great places to spot fossils. In the walls along the road between Blanchland and Pennypie you can find plant fossils and even the burrows of creatures that lived in soft river sands all those millions of years ago."