Scilly Isles and Cornwall

[Ajai]

Out of interest, does isostatic adjustment apply to anywhere else on the globe? Perhaps the effects on the British Isles are easier to measure as a relatively compact landmass but it's slightly unnerving to find the Ice Age still gets 'blamed'.

The glaciers didn't melt overnight, an ice mass retreats very very gradually which means isostatic adjustment is a very very gradual process. The bald statement of geologists that Cornwall is still sinking or Scotland still rising 'because of the Ice Age' cannot be substantiated. If a coastal area is sinking it might repay the geologists to look elsewhere for the cause.

[Boreades]

Out of interest, does isostatic adjustment apply to anywhere else on the globe? Perhaps the effects on the British Isles are easier to measure as a relatively compact landmass but it's slightly unnerving to find the Ice Age still gets 'blamed'.

The glaciers didn't melt overnight, an ice mass retreats very very gradually which means isostatic adjustment is a very very gradual process. The bald statement of geologists that Cornwall is still sinking or Scotland still rising 'because of the Ice Age' cannot be substantiated. If a coastal area is sinking it might repay the geologists to look elsewhere for the cause.

I'm open to suggestions. What other causes might there be?

[Iona]

It's likely that human goings-on have affected the coast just as much as everywhere else. The most obvious activity is mining, which literally undermines mountains and cliffs. It's just so hard to tell what is natural and what isn't! Even when you ask a geologist they seem unfazed and just say "it won't be there in a thousand years' time", probably their standard cop-out. So, looking at the Gower coast (above where the Red Lady of Pavilland was found) the effects of erosion are clearly seen, yet out to sea Worm's Head and the causeway remain, apparently none the worse for wear.

[Similarly on the Isle of Wight parts of the cliffs e.g. at Ventnor are literally falling down (above the 'dinosaur footprint'). Chalk is not renowned for hardness so presumably the Needles and Alum Bay have no business being there. ]

And what about the Jurassic Coast? It certainly doesn't look natural.

[Malmaison]

So, looking at the Gower coast (above where the Red Lady of Pavilland was found) the effects of erosion are clearly seen, yet out to sea Worm's Head and the causeway remain, apparently none the worse for wear.

I take it that you are inferring these are man-made constructions. Do your examples of Welsh limestone cliffs or IoW chalk apply equally to Cornish granite?

[Stuart]

The church overlooking Worm's Head literally fell into the sea and had to be rebuilt further inland.

The original church at Rhossili spent its early days at the foot of Rhossili Downs known today as the Warren. The church here, possibly dedicated to a St. Sulien or St. Sili, with a history stretching back to the 6th Century, was further built upon by the Anglo-Norman settlers some time before 1150. There is even exists some documentation in early charters that Rhossili was the site of an even earlier monastic settlement dedicated to St. Cynwal. However, it is claimed that during the 13th century, huge storms erupted which lashed the west coast of Gower with forceful winds and rain, engulfing both village and church with a mountain of sand.

Compare with Cornwall e.g. Church Cove Gunwalloe where the church, dedicated to St Winwalloe, is right on the edge of the beach.

Beware of strong undercurrents. Deep shelving at high tide. Shifting soft sand. Unstable cliffs and falling rocks. Large breaking waves.

Church Cove offers a safe haven to passing ships. Not the first place you'd expect to find a church but it's lasted...

A small stream runs through the middle of the sandy beach at Church Cove. This may have been used for tin streaming but at any rate the resemblance between churches and engine houses is quite striking, cf. Wheal Coates, Chapel Porth, St Agnes (which used to be an island)

[hvered]

The finest tin in Cornwall was from St Agnes.

Trevaunance Cove is a pebbly plateau at the foot of St Agnes. In the seventeenth century a pier and harbour were constructed and washed away more than once, it must have been an important cove.

Some of the sea caves are very old and feature in Cornish lore, often to do with giants. The cliffs of St Agnes are no exception.

A greater earthen bulwark believed to date from the Dark Ages. It originally ran from Chapel Porth to Trevaunance Cove. Legend has it that Bolster was a giant who fell in love with a young maiden called Agnes. As proof of his love Agnes demanded that the giant fill a small hole at the edge of the cliff with his blood. Being such a small hole the giant willingly did so. However, unbeknownst to him, the hole was bottomless and opened into a sea cave. Bolster continued to fill the cave until he was so weak that he fell into the sea and was no more (the blood stained cave may be found at Chapel Porth).

Bolster the giant is celebrated every May 1st and in fine Megalithic style by a Knight, Sir Constantine, who with other local dignitaries challenges Bolster to a fight to the death.

[Donna]

A greater earthen bulwark believed to date from the Dark Ages. It originally ran from Chapel Porth to Trevaunance Cove.

Bolster is another word for bulge or pillow. Associating gigantic earthworks with gigantic people is quite common and constitutes "evidence" of the mound's unnaturalness. Six miles apart suggests the mounds were intervisible.

In the time of giants in the Penwith area of Cornwall, there lived a particularly troublesome giant called Bolster, who was of such enormous stature that he could stand with one foot on Carn Brae, and the other on the beacon near St Agnes, a distance of 6 miles. Bolster himself was a terror to the surrounding countryside, stealing sheep and cattle from the ordinary Cornish people.

Sounds like a frightening, certainly an unpopular, activity was being carried out. Mining/smelting? Giants in folklore often owned piles of treasure.

According to folklore, a giant called John of Gaunt lived on this ancient site. The giant had a rivalry with another local giant called Bolster.

The two would often engage in battle and throw boulders at each other. The many large erratics found in this area are supposed to be remnants of their battles.

Giants tossing hammers or throwing boulders across a valley has a very Megalithic ring to it.



From the photo Carn Brea looks far more desolate than the surrounding countryside. Its 'ramparts' have been dated to Early Neolithic, excavations here led to the coining of the somewhat vague term 'tor enclosure' presumably because no-one knew what a site like this, in use for millennia, was for. Could be a slag heap.

[Ajai]

Not sure if it's just the pic but the 'slag heap' looks reddish. Carn Brea is close to Redruth ... Wiki says the reddish colour derives from the lead, tin, copper etc. streamed in the river

The name Redruth (pronounced 'Red-rooth') derives from its Cornish name, Rhyd-ruth. Rhyd an older form of 'Res', which is a Cornish equivalent to a ford (across a river), a common Celtic word : Old Cornish rid; Welsh rhyd (Old Welsh rit); Old Breton rit or ret, Gaulish ritu-, all from Indo-European *prtus derived word in -tu from the root *per « to cross, to go through »; Proto-Germanic *furdúz (English ford, German Furt); Latin portus, all related to the Celtic word.[2] It is the -ruth (and not the Red- part of the name) which means the colour red.

[hvered]

There's a St Agnes in the Scilly Isles which also has a 'bolster' joining St Agnes to the island of Gugh. Dunno if it's a man-made earthwork (any tales of giants welcomed)

[Boreades]

Sounds like commercial rivalry, competing for control of valuable sources.
Except, what's John of Gaunt doing there?
Variously a school in Wiltshire, or 1st Duke of Lancaster.