Will a beach always be a beach?

[flobadob]

We were walking the beach tonight and I was telling my son that the sand is made up of dead sea creatures crushed up over millions of years, I hope that is correct for a start. But will places that are beaches now remain beaches or what will they become over a few more million years?

[venator]

Not a chance. The whole shooting match is shifting - this is the current idea - http://en.wikipedia.org/wiki/Plate_tectonics.

So don't book your beach hut for more than a hundred thousand years or so

[hc4361]

You used to be able to walk to Scandinavia from Scotland, so the answer has to be no.

When I say walk, it wasn't a stroll but the land was dry.

[jno]

many of our ancestors (those in central England, anyway) walked here from somewhere around Ukraine, before rising sea water created the English Channel. The west coast has been there a lot longer, though.

Even if land masses move, they may take their beaches with them. The coast near Rio may have been in the same place for about 500 million years (though the continent of South America has moved all over the place).

So the answer is maybe

[EDDIE51]

Most sand is rock finely ground up mainly quartz, so I am afraid it was never made up of dead sea creatures . I think you are getting confused with coral which is made of dead sea creatures , some sand contains a lot of coral though so you are partly right.

[boxtops]

Sand is weeny stones, there are no doubt some skeletons of long-gone beasties in there too, but Eddie is right - it's mostly ground-up stones from the sea constantly beating the cliffs and sea bed.

[flobadob]

Yeah, but aren't those stones made up of dead shellfish etc? Also surely Ireland and England are not affected by plate tectonics.

[boxtops]

certainly they are affected by heave as a result of plate movement - the whole of the UK - just look at the angles and rock strata in the cliffs, you can see how they have been pushed upwards out of the ocean thousands of years ago. And no, stones and bones are quite different!

[emmie]

was watching a little piece on news earlier about a place in sussex that has seen much of it's coastline in the last ten years eroded. A business man is trying with the help of loads of money to do something about it, by putting back the beach, it's odd how i can't really explain it. But the upshot is that their businesses are being ruined by this erosion, losing lots of land, where he has a very large caravan park, so he is trying to do something about it. Not very plain i know, sorry..

[RATTER15]

Im sure there will be dead ground up sea creature but the vast majority is make up from ground and pulverised rocks.

[emmie]

good for explaining about the white cliffs of Dover,

http://www.bbc.co.uk/...utheast/white_cliffs/

[boxtops]

Look at Beachy Head and the Jurassic Coast in Dorset - that's cliffs being pounded daily by the sea, and parts causing the cliffs to fall into the sea. That's rock.

[shaneystar2]

It was caused by what they call Longshore Drift em
http://en.wikipedia.org/wiki/Longshore_drift

[emmie]

shaney i did understand but trying to explain it, not easy, as to the white cliffs i did know about that.

[shaneystar2]

There's an interesting bit at the end of that link about ports and harbours and how they effect the coastline .When they did away with our old curved old pier which was built by the Dutch several hundred years ago ( the Dutch know a thing or two about these things ) they replaced it with a pier that goes straight out to sea .This caused the tides to wash differently and our beach to become bigger .In fact groynes appeared that nobody had seen in living memory .It also caused a beach further up around the headland to disappear altogether .

[askyourgran]

We have suffered from erosion of the cliffs on the East coast of Yorkshire. This too is Jurassic coastline. A few years ago a Hotel broke up and slid down the cliffs in Scarborough. Several park homes are now quite near to the edge of the cliffs. Residents have had to move away, no-one will buy their home now.

[emmie]

sometimes we interfere at our peril, but i do know large parts of coastline are being eroded.

[shaneystar2]

Same here further down the coast AYG .Houses falling off the cliffs .
In fact there's a whole lost village out there somewhere called Dunwich.
My Dad used to tell me a tale ( he was a trawlerman) that on a stormy night you could hear the church bell ringing under the water .
http://www.hiddenengland.com.ar/dunwich.htm

[seadogg]

An important factor on the rise and fall of beaches has been the most recent ice age which caused the land to be depressed under the weight of ice and to rise up when the ice melted. These changes can occur in a few thousand years whereas the changes brought about by plate tectonics happen over a much longer time scale.

[emmie]

the chap who was on this news item said that the main erosion had happened over the last ten years, and it was a vast amount of land.

[askyourgran]

Thats right em10 in the last 10 years the whole coastline is changing, due to erosion.