|
|
FRONT PAGE
ABOUT NRHG TROWSE TRIANGLE NATURAL HERITAGE HISTORY INDUSTRY PEOPLE FOR SCHOOLS NEWS 
|
And underneath it all This simplified cross section through the city centre shows the various natural geological layers that lurk beneath the disturbed surface deposits. There's a range of different soil types on the valley sides, from brickearth to gravel; you name it and it's been quarried at some stage. There are also extensive chalk pits, in fact you'll eventually find chalk at depth wherever you dig, but you'd need an aqualung for the lower ground below river level, which is entirely saturated.
|
Meanwhile, back on the lilo, you've rounded the sharp bend by Cow Tower and are drifting down towards Riverside.
On your left the steeply rising ground is formed of chalk topped by sand and gravel dropped by melting glaciers
a few tens of thousands of years ago. The lower, flatter ground on your right is an old riverside marsh underlain
by peat and silt. This switches across to your left as you pass Foundry Bridge; because of the soft soil all the
new buildings there have to have deep piled foundations.
|