On the subject of England's south coast has anyone noticed something interesting about the beaches along the English Channel?
https://en.wikipedia.org/wiki/English_Channel#/media/File:English_Channel.jpg
At Folkestone, near the eastern end of the English Channel on the England side, the beach is sandy.
https://en.wikipedia.org/wiki/Folkestone#/media/File:Fstone.jpg
But if we continue westward to Hastings, the beach becomes stony.
https://en.wikipedia.org/wiki/Hastings#/media/File:Hastings-wyrdlight-1201.jpg
Further west, at Eastbourne, the beach is still stony.
https://en.wikipedia.org/wiki/Eastbourne#/media/File:Eastbourne_Beach_-_geograph.org.uk_-_1582936.jpg
At Brighton, the stony beach continues.
https://en.wikipedia.org/wiki/Brighton#/media/File:Brighton_Pier_at_dusk.jpg
At Bognor Regis, there is still a stony beach.
https://www.google.com/maps/@50.7819177,-0.6714578,3a,75y,91.84h,90t/data=!3m8!1e1!3m6!1s-0IaYzQAJgEE%2FVzcMFrgiHlI%2FAAAAAAADeKE%2FnU-IJp6JwnYvo8GOwQyKFc0z_fU4gagiwCLIBGAYYCw!2e4!3e11!6s%2F%2Flh3.googleusercontent.com%2F-0IaYzQAJgEE%2FVzcMFrgiHlI%2FAAAAAAADeKE%2FnU-IJp6JwnYvo8GOwQyKFc0z_fU4gagiwCLIBGAYYCw%2Fw203-h100-k-no-pi0-ya324.91153-ro-0-fo100%2F!7i8704!8i4352
But low tide at Bognor Regis reveals sandy beach further from shore.
https://en.wikipedia.org/wiki/Bognor_Regis#/media/File:Bognor_Regis_The_Peir_1.jpg
However if we continue west to Bournemouth, past the Isle of Wight, the beach goes back to being sandy.
https://en.wikipedia.org/wiki/Bournemouth#/media/File:Bournemouth_Pier_-_geograph.org.uk_-_1088741.jpg
On the French side of the English Channel, the beach at Boulonge Sur Mer is sandy.
https://en.wikipedia.org/wiki/Boulogne-sur-Mer#/media/File:Boulognesurmer_borddemer.jpg
But if we move westward along the coast, the beach at Sainte Valery En Caux is stony.
https://www.google.com/maps/@49.8701456,0.7177789,3a,75y,94.35h,90t/data=!3m8!1e1!3m6!1s-E1r1p8jSMVE%2FWE_IFGDmeNI%2FAAAAAAAAADA%2FPDimGAUgB4YhrgTZX3vFowPUpwAVx3kpwCLIB!2e4!3e11!6s%2F%2Flh5.googleusercontent.com%2F-E1r1p8jSMVE%2FWE_IFGDmeNI%2FAAAAAAAAADA%2FPDimGAUgB4YhrgTZX3vFowPUpwAVx3kpwCLIB%2Fw203-h100-k-no-pi-0-ya110.738045-ro0-fo100%2F!7i8704!8i4352
Continuing westward, the beach at Fecamp is still stony.
https://www.google.com/maps/@49.7622267,0.3631675,3a,75y,270h,90t/data=!3m8!1e1!3m6!1s-zLZgs6wkDI4%2FVyoVAerDh2I%2FAAAAAAAAGyo%2FI6-zGGRSyj4_xIxlQjyGtP6vSqB-eNRfQCLIB!2e4!3e11!6s%2F%2Flh5.googleusercontent.com%2F-zLZgs6wkDI4%2FVyoVAerDh2I%2FAAAAAAAAGyo%2FI6-zGGRSyj4_xIxlQjyGtP6vSqB-eNRfQCLIB%2Fw203-h100-k-no-pi-0-ya203.5-ro0-fo100%2F!7i8704!8i4352
But if we continue west to Le Havre, the beach goes back to being sandy.
https://en.wikipedia.org/wiki/Le_Havre#/media/File:Le_Havre_Vue_Plage_14_07_2005.jpg
The reason is that France and Britain were connected by land, but the last remaining isthmus between the two was swept away by moving glacial ice during the last ice age. Sand comes from the action of waves gradually breaking down rock into particles, over long periods of time. The stretches of stony beach, which is longer on the English side, are areas that only became beaches with the last ice age, which ended about 12,000 years ago.
There has not been enough time since then for the waves to break the rocks on the beach down into sand. The rocks have been broken down into small pebbles, but not yet into sand. The areas of sandy beach have been beach for much longer.
The reason that there is sandy beach visible at low tide at Bognor Regis is that the beach was not suddenly cut away by glacial ice there. The rock has been gradually being broken down by waves. Ice age movement of glacial ice will break loose some rock from higher ground above the beach, and the waves will proceed to gradually break it down.
How about the spectacular mesas and buttes of the U.S. southwest?
https://en.wikipedia.org/wiki/Monument_Valley#/media/File:Monumentvalleyviewfromnorth.jpg
This involves a much longer time frame than the ice ages.
Millions of years ago, this land was a seafloor. Waves gradually broke a lot of rock down into sand. The sand continuously piled up on the bottom of the sea. The sand below was compressed into sandstone by the weight of the sand above. This continued for a very long period of time.
Then, the seafloor was forced upward by tectonic movement, so that it became dry land. The water drained away, and any trapped water eventually evaporated. This is why Great Salt Lake, in Utah, is salty, it is left over from the former sea.
But before the sea had drained away, some kind of meteor landed, and introduced one or more new chemical elements into the water. Eventually, all that remained of the sea was puddles and small areas of water, and the newly introduced chemical elements was concentrated in these puddles. When that remaining water evaporated, the newly-introduced elements became part of the top layer of sandstone.
This made the top layer of sandstone stronger, but only in those very limited areas that had been puddles and small areas of water, before all of the water evaporated. Sandstone does not last forever, and gradually weathers away. But the strong top layer protected the sandstone from erosion in these limited areas, and they remain today as the buttes and mesas.
This is how the Niagara Escarpment formed, from uneven erosion due to the protection of a stronger top layer of limestone, which shielded the layers below it, but only in the area that it covered. Egypt has the same king of landscape as the U.S. southwest, it is easy to see the layers of sandstone, but lacks the buttes and mesas because no such meteorite landed there.
Finally, we come to the Grand Canyon of the U.S. southwest.
https://en.wikipedia.org/wiki/Grand_Canyon#/media/File:Grand_Canyon_view_from_Pima_Point_2010.jpg
This is easily explained by the ice ages. At the end of each ice age, when the glacial ice melts as the temperature warms, there is a vast basin area amid the mountains that fills with water to form a virtual sea. This basin area, not the same thing as the Great Basin, is centered around Glen Canyon and is drained by the Colorado and Green Rivers.
At the end of each ice age the water rushes out and, in doing so, cuts away the sandstone. Eventually, after many ice ages, we have canyons such as the Grand Canyon and Glen Canyon.
As another example of the effects of such volumes of flowing water, at the end of each ice age, look at this photo from the far west of Texas, near the Rio Grande River which was also a route for massive volumes of draining water. Notice how smooth and rounded the rocks are, like pebbles on a beach. This can onbly come about by the action of moving water on the rocks.
http://photos1.blogger.com/blogger/5492/3756/1600/dc_250990.jpg
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