The Reading Beds

Tertiary

When global temperatures finally fell again (65 million years ago), sea level fell too. The landscape of Bedfordshire was a flat chalky wasteland. Although we know a lot happened here over the next 63 million years, including huge rivers criss-crossing the landscape and the sea returning on more than one occasion, we do not have any useful evidence of this period, known as the Tertiary.

Bedfordshire has one tiny Tertiary outcrop in the very south of the County, a splodge of Reading Beds. These contain a mottled clay overlain by sands. The clay represents a fossil waterlogged soil deposited around 40 million years ago, and which became swamped by an estuary, represented by the sands. The clays are famous for producing excellent quality bricks, but are better known and more plentiful in the Reading area of Berkshire.