Occasionally, the Reading Formation reveals evidence of luxurious tropical vegetation.
At Felpham, the unusual preservation of fossil wood (lignite) in the form of organic-rich
clays and fossil logs is revealed at low tide. The stumps of palm trees, fossil leaves
and seeds can also be found. This site has been designated a Site of Special Scientific
Interest (SSSI) because of its national importance.
One of the fossil tree stumps from Felpham, lying in the clay in the position in
which it grew around 55 million years ago. The wood is mostly replaced by pyrite
(iron pyrites or fool’s gold). Pyrite is an iron sulphide mineral, FeS2, and very
unstable. Specimens usually oxidise and decay into acidic iron sulphate, which makes
them very difficult to preserve.
This is the site of a Roman tile-making site near Dell Quay on Chichester Harbour.
The kilns used the clays of the Reading Formation to manufacture tiles.
A period of uplift followed deposition of the Chalk, providing a land surface on
which the Reading Formation was laid down. The sea had retreated eastwards whilst
to the west lay the uplands now occupied by south-west England and Wales. Much of
the Reading Formation is make up of well-weathered fossil soils, such as these seen
here in Chichester Harbour. Fossils are very rare.