Marsden Rocks and Cleadon Hills

The cliffs at Marsden Bay are spectacular even in December. Composed of 16-20 metres of cream and buff dolostone of the Concretionary Limestone formation, commonly referred as the Mag limestone formed in the late Permian period. The large sea stack in the picture below is composed of collapse-brecciated Concretionary Limestone.  Stacks like Marsden Rock were once joined to the mainland but weaknesses in the limestone create caves, arches and stacks over time. A spectacular coast is the result.

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The cliffs are made of layers of Magnesian Limestone which formed in the ancient Zechstein Sea. Within the original rock sequence was a thick layer of a soluble salty mineral (Hartlepool Anhydrite), which formed during a period when the Zechstein Sea evaporated and became saltier. After millions of years, the sequence was tilted and uplifted above sea level and the anhydrite dissolved away. The limestone above it collapsed and broke up. These broken up and fractured rocks are known as ‘collapse breccias, they are visible in the deformed cliffs below on the bottom right hand corner.

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Seabirds use these coastal features for nesting. Although the fulmar pairs below won’t be nesting until May, the female has glands that store sperm to allow weeks to pass between copulation and the laying of the egg.

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Sinkholes are a feature of this coastline.

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These impressive limekilns were built in the 1870s. Layers of limestone and coal were dropped in the top and burnt to make lime, which was used to improve acid soils and to make cement and concrete. Lime was also important for the steel and chemical industries. Coal sourced from from Whitburn Colliery fired the kilns. A village was built to house workers for the colliery and limeworks. After the colliery closed in 1968 the village was no longer needed, people moved to new houses nearby and the village was demolished. The cliff-top grassland where the village stood became a grassland of lime loving or calcicole plants.

OLYMPUS DIGITAL CAMERAThis windmill was built in the 1820s on the highest part of Cleadon Hills. The building incorporates a stone ‘reefing stage’, a platform around the base of the windmill, which was used to access the sails. Look for the unusual rippled and dimpled textures in the tower walls composed of concretionary limestone.OLYMPUS DIGITAL CAMERA

Cleadon Hill is a ridge of high ground standing between the village and the coast. Around 260 million years ago the hills were, together with others in the area, a group of small low islands in a tropical lagoon formed by the Zechstein Sea. Is it a conservation area due to its plant-rich magnesian grasslands. Exmoor ponies are helping to maintain the flower rich areas by grazing the rougher grass species.

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Some lichens prefer limestone as a substrate such as bright white Aspicilia calcarea below, growing on a wall.

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and the orange yellow rosettes of Caloplaca flavescens.

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The site is also dominated by the landmark Cleadon Water Tower, in fact a chimney for the former steam-powered pumps, which is visible for miles around, as far south as the Headland in Hartlepool.

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The views to all sides are worth the short climb. To the South, Roker pier is visible,

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while looking to the North, Tynemouth Pier and Priory are prominent.

OLYMPUS DIGITAL CAMERAMarsden Old quarry is a Nature Reserve forming a patchwork site of a variety of habitats which include areas of lowland meadow and pasture, magnesian limestone grassland and some semi-improved neutral grassland. This site of approximately 6.3ha supports an abundance of wildflower species such as Kidney vetch, Hoary plantain and Common Bird’s-foot Trefoil as well as Lady’s Bedstraw and Bee orchids. The geology is also of great interest and worth further exploration.

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Gorse (Ulex europaeus)is always a thorny subject but this one was not in flower.

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With the coming evening the clouds were colouring up over the golf course,

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and The Cheviot hills unmistakeable in the distance.

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Reference:

Durham coast SSSI

A Magnesian Limestone Geotrail

Cleadon geology

Bolam and St Andrews church

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It was a cold day when the Botany group went for a winter walk at Bolam. The Lake is artificial, designed by John Dobson and constructed in 1816 for the Rev John Beresford, who became Lord Decies in 1819. Beresford wanted to help local people through the agricultural depression and upheaval after the Napoleonic Wars by providing employment. It was, however, a fashionable enterprise since his neighbours were busy making improvements to their estates. Sir Charles Monck was undertaking building and landscaping work on Belsay Hall and grounds, while Sir John Trevelyan created a grand estate at Wallington landscaped by Capability Brown.

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In spite of the cold some fungi were flourishing, Velvet Shank (Flamulina velutipes) had colonised this tree trunk.

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St Andrew’s Church has a square late Saxon Tower but the interior is largely Norman with the arcading dated to 1180-1200. The quatrefoil piers with their broad moulded capitals are unique to St Andrew’s.

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These mysterious Saltire crosses inscribed on a pillar inside are presumably in honour of the martyrdom of St Andrew.

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Medieval gravestones bearing skulls and crossbones were common. The name is obscured by lichen but the message of ‘memento mori’ is still visible. Lichens are long lived and thrive on old gravestones. The lichen with the black apothecia looks like Tephromela atra while its neighbour with the red/brown discs is Trapelia coarctata.

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Ramalina farinacea, the bushy lichen and the bluish leafy Parmelia saxatilis are pictured on another stone below.

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From the churchyard the view shows the stretched ovoid form of a drumlin and craters in the foreground, formed in 1942 when bombs fell from a German Dornier airplane.

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Two roe deer can be seen running across the fields adding to a memorable winter scene.

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OLYMPUS DIGITAL CAMERA Although hardly discernable to the eye, a large flock of Brambling were feeding in this Beech tree. Members of the group observed Coal and Marsh tits, Redwing, Tree creeper, and Buzzard.  OLYMPUS DIGITAL CAMERA

In spite of the frost some plants were flowering, like this Daisy (Bellis perennis) growing among Parsley piert (Aphanes arvensis) on the bank of this ha-ha. A ha-ha is a recessed landscape design element that creates a vertical barrier while preserving an uninterrupted view of the landscape beyond.

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Peltigera lichen was thriving on the mossy bank. Most Peltigera species have the cyanobacterium Nostoc as the dominant algal partner but some contain small gall-like growths of the chlorophyte Coccomyxa containing Nostoc. Because of their ability to fix nitrogen from the atmosphere, such lichens are influential in soil composition and generation.

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An ornamental ivy, probably Canarian Ivy (Hedera canariensis) naturalised on a roadside verge added a seasonal interest.

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Reference: https://www.northumberland.gov.uk/NorthumberlandCountyCouncil/media/Neigbourhood-and-Local-Services/Parks%20and%20open%20spaces/Bolam%20Lake%20200years%20project/17957-Bolam-Interpretation-Booklet-A5-Print2-LR.pdf

Pike Law

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At 530 m elevation in the North Pennines, Pike Law is an upland moorland well known for centuries of lead mining. The photo shows a rushy moorland now used for sheep grazing and grouse shooting, with Cross fell, at 893 m visible on the skyline.

Although the bedrock is of Carboniferous age, it is covered in more recent glacial deposits, such as the drumlins in the picture below. Composed of till, or boulder clay, they form large rolling ovoid features in the landscape.

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We explored the West End and flask hushes in an area widely scarred by these huge extractive fissures. The West End hush shown below is 300m from East to West and 170m from North to South. This hush has a SSSI status for its fine exposure of mineralized Great Limestone in which many features both of the original limestone, and its subsequent alteration are clearly displayed. The supergene mineralisation (processes or enrichment that occur relatively near the surface) can be seen here, both in the exposed rock face and the abundant debris at its foot.

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The dark grey crystalline mineral shown below is Galena. It the natural mineral form of lead(II) sulfide (PbS), the most important ore of lead.

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Fluorite, calcium fluoride, CaF2 was also mined here but regarded as a waste product. It is found in numerous spoil heaps, occurring as purple or yellow crystals.

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Potamogeton polygonifolius or bog pondweed, is an aquatic plant. It is found in shallow, nutrient-poor, usually acid standing or running water, bogs, fens and occasionally ditches. It seems to be thriving in the wet hush bottom.

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The Flask Hushes have limestone outcrops forming their walls. The west end of these hushes show some structure with the top of the limestone visibly dipping at 30 degrees to the SW, weathering to a brown colour, with open joints, probably associated with the fault/ vein running along the hush,

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Leat dams and reservoirs are a feature at the head of the hushes. Probably the dams were formed from boulder clay and the reservoir water used to flush minerals out of the veins and spoil downstream.

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The area has been extensively worked by shaft and Adit over the centuries. In the bottom of the east end of the hush there are traces of an Adit with large boulders tumbled over its entrance.

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The Great Limestone forms the Southern wall of the hush, looking from the North, it appears dip gently to the West. It is being overlain by flaggy sandstones and mudstones.

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One of the mysterious features of the area are these boulder lines found at the head of outwash fans. Composed of limestone and sandstone rocks, they line one side of the ditch in long swathes. There origin is obscure but seem to have been deposited by mining and outwash processes.

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The Great Limestone is noted for its fossils. Dibunophyllum bipartitum is shown in both photographs below. It is a solitary rugose coral of the Carboniferous. The picture below gives a cross-sectional view with the septa visible.

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A longitudinal view reveals coral to be about 10cm long.

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Waxcaps are a sign of old cropped unimproved grassland. A Ballerina waxcap (Porpolomopsis calyptriformis) showing its skirts off. They are thought to have a mutualistic relationship with mosses.

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Lichens like the conditions up on this moorland. This shining brown Cetraria aculeata is one of the many types.

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Reference: https://designatedsites.naturalengland.org.uk/PDFsForWeb/Citation/1003630.pdf

http://northpennines.wp-sites.durham.gov.uk/wp-content/uploads/sites/37/2018/11/Pike-Law-geology-report-by-Colin-Fowler.pdf

https://www.bgs.ac.uk/discoveringGeology/time/Fossilfocus/coral.html

Blackhall Rocks

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This beach photo taken from the top of the Magnesian limestone cliff outcrops laid down during the late Permian ( 300-250 mya). Formed by lagoonal deposits left by the rising and falling levels of the Zechstein sea, various formations can be seen including the Hesleden Biostrome from the beach.

A closer view of the rubble on the beach reveals a stony residue of colliery waste dumped on the beach from local mine workings. The colliery closed in the 1990’s but it was left for the tides to disperse the spoil out to sea. There is still a detectable sulphurous smell.

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The cliffs look more imposing from the beach.

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The laminations in the Biostrome are visible from close up as tightly packed thin layers. Finely laminated horizontal layers within the rock, each no more than a millimetre thick were formed from layers of filamentous blue-green algae that gradually accumulated on the shallow bed of the tropical sea. The Biostrome consists almost entirely of dolomite rock and comprises a thick and highly varied boulder conglomerate overlain by a thicker unit of algal laminites. The conglomerate is formed mainly of rolled cobbles and boulders derived by erosion of the underlying (but unexposed) reef-flat rocks of the Ford Formation.

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Stromatolites occur in the form of large domes up to 20m across and 3m high, pictured below. They are intriguingly displayed on the shore. Structures of this size are currently unique to the UK, and rare in marine Permian strata generally.

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They are more difficult to spot in the cliffs, however, this picture shows the convex dome shaped ‘Crinkly Beds’ of this upper (stromatolitic) part of the biostrome.

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Evidence of a fault is shown below in the different strata on either side of the slipped glacial till. This fault between Limekiln Gill and Cross Gill brings the Seaham Formation and Seaham Residue (left) into contact with the Roker Dolomite Formation (right). The base of the Roker dolomite rises to the cliff top beneath the boulder clay.

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A closer view of the Seaham residue, predominantly thin-bedded limestone (calcite mudstone/wackestone with some interbedded coquina , packstone, grainstone, mudstone and concretionary limestone) with some dolostone.

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Towards the south, a block of the Roker formation had fallen on the beach. Not only were mud slides dripping down the cliffs; occasional rock falls littered the beach. The area, in the longer term, is under going progressive erosion.

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The Roker formation is a cream, oolitic dolostone with subordinate thin beds of fine-grained dolomite and breccias. It rests on the Concretionary Limestone Formation (seen above at the bottom) as rounded cannonball-like strata that occurs above the Hartlepool Anhydrite Formation offshore with a dissolution residue that overlies the Ford Formation onshore.

The glacial tills are 24 m deep of southwards-thickening Quaternary (late Devensian)  deposits overlying up to 10 m of Magnesian Limestone. They form a layered sequence of two stony clays separated by a sand and gravel layer from which perennial seepages cause instability and slips.

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The site is noted for cliff top magnesian grassland and plants such as Sea Spleenwort (Asplenium marinum ). It grows in crevices and fissures in rocks, caves and walls near the sea and within the sea-spray zone.

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The beach at Black Hall Rocks contains some of the largest cave formations to be found on the Durham coastline, the magnesian limestone cliffs here measure 15–32m in height. The Gin Cave is an example of a Sea (Littoral) Cave. Colourful red algae, probably Hildenbrandia rubra decorates the walls.

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A  tantalizing view of the beach from within one of the caves. Caves are formed by the action of destructive waves hitting the cliffs with great force. The action concentrates on weak points within the rock, this may be a fault line or the bedding planes of sedimentary rocks, such as limestone.

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Caves in headlands may eventually erode right through to create an Arch in the rock. This will continue to erode and eventually the arch will collapse leaving a free-standing pillar of rock known as a Stack. The coastline here used to feature many stacks. These are no longer present through either natural causes or human intervention.

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A group of ringed plover and a few Redshank were seen patrolling the tideline.

 

 

Reference:

http://archive.jncc.gov.uk/pdf/gcrdb/GCRsiteaccount3016.pdf

https://designatedsites.naturalengland.org.uk/PDFsForWeb/Citation/1000255.pdf

https://www.geocaching.com/geocache/GC205F8_gin-cave-earthcache-black-hall-rocks

Roseberry Topping & Cleveland Dyke

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Roseberry topping is an erosional outlier of the Ravenscar Group on the western edge of the Cleveland escarpment. The area was extensively glaciated and the stratigraphy dips towards the South- Southeast.

The photograph above shows Newton Wood- mostly of Sessile Oak , Ash and Hazel of some age and probably planted on ancient woodland soils. It is noted for its springtime native bluebell and Stitchwort woodland floor plants. It occupies the glacial till overlying the Redcar mudstone formation  described by the BGS as grey fossiliferous, fissile mudstones and siltstones with subordinate thin beds of shelly limestone in lower part, and fine-grained carbonate-cemented sandstone in upper part.

On climbing up through a woodland path we came across bedrock of the Staithes formation shown below. Described as silty sandstone, more or less argillaceous (clay), typically intensely bioturbated and/or showing bedding structures of many types. Bioturbation is defined as the reworking of soils and sediments by animals or plants. These include burrowing, ingestion and defecation of sediment grains. These activities have a profound effect on the environment and are thought to be a primary driver of biodiversity.

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Out of the woodland we emerged onto a bench in the landscape formed by the Cleveland Ironstone formation.OLYMPUS DIGITAL CAMERA This formation of mudstone, silty, argillaceous siltstone and silty sandstone with seams of sideritic and berthierine-ooidal ironstone, occurs typically at the tops of small scale sedimentary cycles. The land here was quite disturbed and hummocky, vegetated with rough pasture and gorse bushes. The rich red colouring  from rabbit burrows shows the presence of red Ochre. Red ochre, Fe2O 3, takes its reddish colour from the mineral hematite, which is an anhydrous iron oxide.

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Although probably mined since prehistoric times Roseberry ironstone mine was commercially founded in the 1870’s and continued until the 1920’s. Underneath Roseberry Topping is a labyrinth of mine workings, some think responsible for the slope collapse visible at the peak. We passed an ancient European Larch tree, a deciduous conifer looked as if it have been growing here for centuries, part of a larger plantation that once flourished here. Larch’s presence in the UK was first mentioned in 1629 and itt soon became a popular plantation tree.

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The track of a mine tramway still exists, stones along the surface showing evidence of many fossils like this one – possibly the bivalve Venericor.

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Lying above the Ironstone formation is the Whitby Mudstone formation of medium and dark grey fossiliferous mudstone and siltstone, laminated and bituminous in part, with thin siltstone or silty mudstone beds and rare fine-grained calcareous sandstone beds; dense, smooth clayey limestone nodules very common at some horizons.  Beds of Grey and Alum shale occur showing up on the grey grey crumbly slopes covered in distinctive brown bracken. Bracken likes dry, slightly acid soils under 450 metres.

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Jet is a type of lignite, a precursor to coal, and is a gemstone. It is derived from wood that has changed under extreme pressure and thin beds occur in the Whitby Formation. Spoil heaps from a Jet mine below the Topping supported different types of plants more typical of Heathland- Heather, bilberry, rich mosses and many lichens such as this cladonia diversa.

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Moorland fungi such as the Moor Club pictured below forms relationships with Heather, thriving amongst the lichen (Cladonia furcata?)

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The Saltwick Formation forms the craggy peak and most of the Cleveland escarpment tops. Consisting of grey mudstone, yellow-grey siltstone and yellow, fine- to coarse-grained sandstone, the sandstones commonly display sharply erosional bases, and channel-fill bedforms. Plant remains and plant rootlets are common in some beds.

The picture below shows thick channel sandstone with some cross-bedding. Although sauropod and stegosaurus footprints have been found in this Middle Jurassic formation, none were visible here.

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The view from the top shows the deltaic beds of the Saltwick formation snaking across the Cleveland hills into the mist.

 

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The Cleveland Dyke is an igneous intrusion which extends from Galloway in southern Scotland through Cumbria and County Durham in northern England to the North York Moors. The dyke is associated with volcanism which took place in the Isle of Mull igneous centre in western Scotland during the early Palaeogene Period. During a time of regional crustal tension associated with the opening of the north Atlantic Ocean,  innumerable dykes were emplaced across the region. It has been extensively quarried along the Langbaugh ridge at Cliff Rigg for roadstone and setts destined for Leeds. Half a mile in length, quarrying began in 1869 and production stopped in 1918 leaving a huge gully in the landscape.

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The treeless gap marks out the course of the dyke as it makes its way to the North Sea.

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This photo shows the elevation of the ridge formed by the Dyke with the dramatic Cleveland hills forming the backdrop.

 

References

Yorkshire Rocks and Landscape: A Field Guide (Rocks & Landscape)  Apr 1994
by Yorkshire Geological Society (Author), Colin Scrutton (Editor)

BGS -Lexicon of named units  BGS

 

Castle Head and Friar’s Crag

 

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The view in the pictures show the difference that 182m elevation make to the range of visibility. The top photo is taken from Friar’s Crag, a popular point made famous by John Ruskin. The lower one, from Castlehead crag, provides a panorama of many peaks: Skiddaw, Grizedale Pike, Robinson, Blencathra among them.

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Both crags are intrusive geological features not part of the Borrowdale volcanic group. Formerly the rock, shown below was thought to be dolerite but now due to its quartz content is defined as Diorite, an intrusive igneous rock strong enough to survive ice age erosion. The pictures shows the dark  colour and fine grained texture.

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Although it was a quick survey there were interesting plants in the woodlands. Common Cow-wheat (Melampyrum pratense) is a semi-parasitic plant growing near Friar’s crag.. Because the seed of the plant has an elaiosome (fleshy structure) which is attractive to wood ants, the ants disperse the seeds when they take them back to their nests to feed their young. Since the ants rarely carry the seeds more than a few yards, the plant is an indicator of ancient woodland.

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European Goldenrod (Solidago virgaurea) in full flower. Bees are attracted to it for its late season nectar.

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Also beloved by bees and insects, Wood Sage (Teucrium scorodonia) looked vibrant.

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Heath Speedwell (Veronica officinalis) had finished flowering but was still recognisable.

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Hawkweeds (Hieracium agg.) were just coming into flower

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Other plants noticed in the woodland: Slender St john’s wort, Harebell, Wood sedge, Common valerian, Great woodrush, Common polypody, Enchanter’s nightshade and Common figwort.

On Castlehead crag there is a deciduous Alantic woodland. Mainly of Sessile oak (Quercus petraea) with Holly, Birch and Hazel understorey. Scots pine had colonized the craggy tops while Stonecrop Sedum album was creeping along the stony cracks and hollows.

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Among the bryophytes Climbing corydalis (Ceratocapnos claviculata) was scrambling.

The site is noted for lichens but need to be covered separately.

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References:

https://designatedsites.naturalengland.org.uk/PDFsForWeb/Citation/1003952.pdf

https://forestplans.co.uk/…/national-trust-woodland-management-plan-borrowdale.doc…

https://www.plantlife.org.uk/uk/discover-wild-plants-nature/plant-fungi-species/common-cow-wheat

Teesdale Waterfalls

Teesdale provides good exposures of Carboniferous Yoredale cycles on the ridge of the Caledonian Alston block. The Whin sill emplacement into the later carboniferous forms spectacular waterfalls on resistant rock. More recent glacial deposition features were also to be seen.

In Bowlees quarry a thick bedrock exposure of Scar Limestone was examined. The beds were dipping gently to the South East.

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The waterfall on the Bow Lee beck seen below was flowing over the Scar limestone although the fall above that was over sandstone. The Scar limestone is visible the large block on the right of the waterfall. The slippage probably the result of movement in the fault. The stream bed showed tell tale ripple marks of sandstone. Yoredale sequences or Cyclothems are repeated geological cycles of limestone-shale-sandstone, seatearth/coal formed in the mid carboniferous.

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At low force the Whin Sill predominates, its crude hexagonal columnar features stand out like broken teeth. Towards the close of Carboniferous Period some 295 million years ago, crustal stretching caused by movement of the Earth’s tectonic plates allowed the emplacement of igneous intrusions of magma across much of northern England in a suite of tholeiitic (quartz) dolerite intrusions. On cooling, these crystallised and solidified to form the Great Whin Sill seen below.

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The light grey rock in the picture below looks like limestone but this is deceptive, since this is the same dolerite rock as the Sill in a weathered state.

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Near Wynch bridge we looked at a sandstone raft left in the Dolerite as it solidified. The picture shows the boundary between grey/brown Whin and paler coarser grained sandstone. The point of contact is a chilled margin, where a thin dark glassy layer of tachylite can be seen.

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While walking up to the High Force drumlins were conspicuous. These shallow egg shaped landforms are depositional features formed by a glacier as it retreats.

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More possible evidence of glaciation seen below in the striations (scratched bedrock caused by glacial abrasion) on this rock.

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High Force is an impressive waterfall where the river Tees drops 21 metres over the Whin sill into a plunge pool below.

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The stratigraphy sequence can be discerned in the rock layers. The dark grey horizontal beds visible on the bottom fight are composed of the Tyne Bottom limestone. The bed directly above is sandstone and the top two vertically jointed beds are the Whin sill. The quartz dolerite magma has been injected into the sandstones and there is a chilled tachylitic margin for those intrepid enough to look for it.

 

 

Reference: Northumbrian Rocks and Landscape Ed by Colin Scrutton.

Claxheugh Rock

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This is an impressive rock by the south bank of the river Wear near Sunderland. On approach a Peregrine falcon took flight from the top.

The river cuts through exposures of  Carboniferous (Upper coal measures) and Upper Permian age. Carboniferous age rocks are exposed on the far shore as a distinguishable,  deeply weathered, purple coloured rock layer below the bright yellow lower Permian sandstone. Between these layers is an unconformity or gap in the geological record.  Permian yellow sandstone have been widely quarried and acted as a porous reservoir for natural gas out under the North Sea.

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Carboniferous strata is also revealed on the Claxheugh side, in crumbly mudstones of different shades of grey. Coal seams were not visible but the dark grey suggests a high carbon content.

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Below the flaky layer, harder sandstone shows the wavy ripple marks indicative of a marine origin.

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These marks on the rocks look like trace fossils left by burrowing creatures.

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The Claxheugh exposures lie entirely within a fault-bounded trough; the Claxheugh fault shown below forms the Eastern edge and the Ford Fault further down, the western boundary of the sequence.

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 A closer view of Claxheugh Rock, derived from Clack’s Heugh, a crag in Mr Clack’s property, reveal the join between the Basal Permian Yellow Sands, Marl Slate, Raisby Formation and Ford Formation above. The reef of the Ford formation comprises a great mass of buff and brown dolomitic bryozoan dolomitic limestone and ancient stromatolites. Their appears to be another unconformity here at the boundary with the blocky Permian sandstone.

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A submarine slide canyon appears as a disturbance feature in the picture below.

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Thin Marl slate facies can be seen below. Comprising finely laminated, buff and grey, dolomitic shale  in brown, carbonaceous, plastic clay, it has been marked by graffiti.

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Besides the Peregrine, the rock was encircled by a ‘train’ of Jackdaws. The tide was low and Shelduck, Curlew, Redshank and Cormorant were seen in small numbers while in the surrounding  scrubby woodlands Chiff-chaff were calling. Although bees and butterflies were zooming around, only Small tortoiseshell butterfly was clearly identifiable.

Once the Hylton ferry ran across the Wear, now the boats look abandoned and there is no crossing now.

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Reference:

http://jncc.defra.gov.uk/pdf/gcrdb/GCRsiteaccount2086.pdf

Bedrock and Building Stones- Dr Andy Lane 2014

Sunderland North Dock Tufa

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The calcareous Tufa Dome shown above consists of the mineral calcium carbonate (calcite). Precipitation from the stream water has formed a geological feature of great interest. Tufa formation is associated with hard-water springs, where groundwater rich in calcium bicarbonate comes to the surface. On contact with the air, carbon dioxide is lost from the water and a hard deposit of calcium carbonate (tufa) is formed. These conditions occur most often in areas underlain by limestone. In this case although no-one is sure, the stream is thought to originate from Permian Limestones in Fullwell Quarry.

A closer view of the stalactites formed by the dripping of water.

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Bramble and ivy has grown over the top,

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while various liverworts, algae and Maidenhair spleenwort are growing underneath. Tufa forms by the combined forces of plant roots, grasses etc which support the precipitating minerals. Gradually they form petrified rock.

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The dome has been preserved by extensive supports and the design for the Marine Activites centre amended. Now it lies, a hidden gem, within the building itself.

 

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The North Dock was built in 1837 and it is thought that the formation has developed since then. It was discovered in 1992.

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Saltburn-by-the-Sea Fossils

This view of Huntcliff Nab shows some of the visible stratigraphy of these imposing cliffs, 365 ft in height (picture from wikimedia). The rocks are upper Jurassic in age and mostly belong to the Cleveland Ironstone formation of the Lower Lias. It was a misty January afternoon when we visited for a brief beach walk. The tide was coming in so we walked the beach towards Redcar.

In the distance on the coast is the former Warrenby blast furnace. The Tata Steelworks plant at Redcar closed finally in 2015 ending a century of steel production. The steel produced at Dorman Long was used to build the Sydney Harbour Bridge, Tyne Bridge and Auckland Harbour Bridge.

Also just visible is the Teesside Wind Farm. A 27 turbine 62 MW capacity run by EDF Energy Renewables and completed in 2013.

This rather alarming picture of the beach shows the rapidly eroding and slumped glacial till deposits.

This glacial erratic of Carboniferous age formed a large 6ft block stranded on the shore. The flattened angular limestone boulder was speckled, displaying many crinoidal fossil pieces in the rock.

On the sand, pieces of grey fossiliferous mud and silt stone of Jurassic age lay scattered probably from the Redcar Formation, containing bivalves of some kind. An example in the picture below shows one of the 2 cm fossil constituents.

The partial fossil below looks like a ‘Devils Toe Nail’ or Gryphaea sp. a commonly found fossil.

Looking like a modern beach shell this crinkled shell is some kind of fossil Brachiopod eroded from an Oyster bed pebble. The underside in the bottom photograph shows some interesting trace patterns.


Although not a fossil this stone was covered in Keel Worm casts.

Not a fossil either, this razor Shell is a modern bivalve of sandy shores.

Pieces of red stone also littered the beach. Beach stone can be difficult to identify but the red colour could be due to the presence of iron. It is probably a piece of ferruginous ooidic sandstone from the ironstone outcrop at Huntcliff.

Reference:

https://www.bgs.ac.uk/lexicon/lexicon.cfm?pub=CDI http://www.tvrigs.org.uk/jurassic-lower.html#sthash.QWS0W0v8.dpbs

Fossils of the Whitby Coast- Dean R. Lomax