The Earth Beneath Our Walking Shoes

We are walking on the thin crust that formed not long after our molten blob ended up as the third rock from the sun. The 60 miles we are walking for our challenge, if we were walking down that far, would take us right through the crust into the “hot blobby stuff” below and our legs would be long gone.

This thin crust floating around on the hot stuff below gets pushed around by the thermals below, crunched up into mountains or stretched out thinner. Under the oceans new crust is still being formed as volcanoes spew out new rock, but generally speaking things have settled down since the crust cooled down and thickened up around a billion years after the blob was formed.

So much so that life has been creating debris on the surface whilst the crust has been pushed about.

So now in London we are standing on layers of dead stuff warped over time by the rumbling hot tummy of mummy earth below us, leaving a big china white dish with a river flowing down the middle as the dish spills out to the north sea. The rims of the dish form the hills to the south and the the hills to the north that we will ramble over to get back home. The rest of the dish has been worn and washed away except for fragments that crop up again to make the white cliffs of Southern Britain and Northern France.

London: sitting in big chalk dish filled with the mud sitting on top of more mud.

all made by life on earth and with the wind and rain fed Rivers bringing In more dead stuff or rocks already Inside the earth before life started up here on her surface

2000 years of Human Debris

The first eighteen feet below us as we stand on our starting line is the debris of Londoners created over the last 2000 years

A million years of wind, rain and ice

Below the debris in the centre of London are patches of gravel brought down by Old Father Thames or blown by the wind long before this place was London

London Clay

but mainly there lies a thick bed of London Clay laid down over millions of years when this place was some place else teeming with non-human life under a tropical sea and before it became dry land.

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