At low tide the Deben estuary exposes mud flats comprised of London Clay. The flats are a favourite haunt for fossil hunters. Sieving through the clay will regularly produce bird and fish remains, vertebrae, small sharks’ teeth and also fossil wood.
From the flats shingle banks rise steeply, the top representing the high water mark. Along this tide line there is a belt, often several metres wide, containing an abundance of seashells – as can be seen below.