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Visit Our Centre

EFC Centre at Wat Tyler Country ParkOur centre is available for visits on a pre-booked basis on Wednesdays between 10am - 4pm. The Club’s activities and displays are also usually open to the public on the first Saturday of the month 11am - 4pm.

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Purfleet-on-Thames

previous pageGeology of Purfleet Commercial Park (Bluelands Quarry) 300,000 years ago Cold Braided river 320,000 years ago Warm Warm Inner estuary, mudflats, sandflats with shell beds 340,000 years ago Cold Deeply frozen ground (permafrost) Aveley North Road North bank of Thames South bank of Thames Thames deposits Bedrock 0km 20m 15m 10m 5m Sea level 05 10 15 River gravel Sands (Thanet Formation) Shelly sand Chalk Laminated Clay (mudflat) Mar Dyke A1306 A13 cutting Bluelands Fractured chalk The uppermost parts of the chalk often show that it has been broken into angular blocks This indicates that in the past the chalk was frozen Water penetrated joints and other fissures to some depth and froze, forming permafrost, breaking the chalk up Shelly sand The species of shell, and other types of fossil, found within these beds show that the climate was warm and the river flow was much like today Sands and shelly sands occur at the sides of rivers rather than in the main stream The shell beds are often found within the laminated clay Laminated clay The laminated (thinly layered) clay represents former mudflats, typical of much of the Thames today, as at Purfleet or Southend Mudflats are associated with the lower reaches of rivers The association with the shelly sand shows that the riverside varied between mudflats and sandy beaches Gravel The gravel shows that the river was very much more powerful than today and had a sandy gravelly bed forming a braided pattern with many channels and gravel bars, like many arctic rivers today Bedding within the gravels can be measured and show that the river flow was to the west The sediments at Bluelands Quarry give us a history from the end of a cold period, through a warm stage (interglacial), into the beginning of the next cold period in the Ice Age Recent research has shown it to have lasted from about 340,000 to 300,000 years ago As a measure of its geological importance, the warm stage is known nationally as the ‘Purfleet’ Interglacial and it is a Site of Special Scientific Interest The site also enables us to contrast the variety of warm stage tidal sediments found at the side of the river, like the foreshore at Purfleet today, with the cold stage gravels in the main path of the river when the flow was powerfulnext page