An Interesting Summary And Geological History of Eastbourne

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Follow this link for a time line history of Eastbourne, or read on to learn more of the geological history of Eastbourne in East Sussex, including fossils, dinosaurs and the formation of the north and south downs.

The geological history of Eastbourne, recorded in the rocks is a tale of flood, volcanism and the birth of oceans and mountains, the rise and fall of sea levels - literally world shattering events – that shaped the land we now see.

The period that these world shaping events took place, that are recorded at Eastbourne, occurred during the middle and latter part of the Cretaceous period, between 103 and 86 million years ago into the tertiary period, about 56 million years ago.

The Cretaceous period saw the final flowering of the dinosaurs, before their extinction at the end of the Cretaceous. At this time, Eastbourne was not land - it was part of a deepening sea, moderately close to land. We will never find the evidence of dinosaurs at Eastbourne, as dinosaurs never lived in the sea (animals such as pliosaurs and ichthyosaurs are not dinosaurs but marine reptiles).

Sadly, there were no dinosaurs in Eastbourne

The oldest rocks that can be found at Eastbourne are the gault clays and the greensands exposed at low water along the beaches to the west of Eastbourne, near Holywell and Cow gap. These rocks are from the middle to lower Cretaceous and are 103 million years old.

The gault clay and greensand represent a moderately deep sea that shallowed slightly and then deepened so that chalk sediments were deposited (and at first being mixed with the gault clay and greensand forming a rock known as the glauconitic marls). This process occurred between 100 and 98 million years ago.

The changes in sea level are driven by a warming of the Earth by an increase in volcanic eruptions and by massive movements in the land, all driven by movements in the crustal plates of the Earth.

Chalk continued to be laid down until the end of the Cretaceous period in Eastbourne, when the sea floor was lifted clear of the sea by an event that occurred in southern Europe. At the beginning of the tertiary plate movements pushed present day Italy into the rest of Europe.

When these two land masses met the resulting crash caused the crust to buckle and form massive ‘wrinkles’. These ‘wrinkles’ became the Alps. The actions that formed the Alps caused ripples to form in Kent and Sussex, forming the north and south downs. This along with erosion, the actions of ice through glacial periods and the birth of the Atlantic Ocean have formed the landscape we now see and enjoy today.

Are there fossils in Eastbourne, and where can these fossils be found? Learn more about finding fossils in Eastbourne or read the time line history of Eastbourne.