Chalk cliffs form in layers separated by bands of flint, which can be seen in the photo below that I took while visiting these cliffs. Due to the structure of the layers, the bottom slabs of chalk are eroded by waves crashing against them. Eventually the lower slabs will be eroded to the point where the upper layers have no support and collapse.
These chalk rock, or calcium carbonate, cliffs were formed over a period of 30 million years when the area was submerged in a warm subtropical sea, between 95-65 million years ago during the Cretaceous Epoch. Shells containing calcite from billions of microscopic marine algae, called coccoliths, created deposits as they died and sank to the bottom of the sea. These deposits were pressed together by the weight of the ocean and eventually formed the layers of limestone over a thousand feet thick. The cliffs were then uplifted due to plate tectonics and continental movement. Millions of years of erosion due to water has created the modern cliff faces we see today. The surrounding area consists of valleys, ridges, and escarpments that were formed by glacier movement during the last Ice Age. As weathering continues from waves and rainfall the cliffs will continue to shrink inwards and collapse onto each other. These types of cliffs are common on the coasts of southern England, other notable bluffs being Seven Sisters and the White Cliffs of Dover. This location is also a great source of fossils, as the chalk and flint layers contain many different fossils of marine life that once lived in the warm sea that covered the area.
Examples of some fossils that can be found in the area.
These cliffs represent the many different processes that occur on the Earth, such as the formation of sedimentary rocks, plate tectonics, weathering, and fossilization. Due to the beauty and history of the cliffs, Beachy Head has become a location visited by tourists, archaeologists, fossil hunters, and anyone with an interest in what the steep face has to offer.
References
“Chalk Grasslands.” Welcome to the White Cliffs Countryside Project Page - How Was
Chalk Formed?, 4 Dec. 2019,
www.whitecliffscountryside.org.uk/index2.php?id_sec=79&id_sub=3&id_art=215&id_img=.
“Geology and Archaeology.” Beachy Head & Eastbourne Downland,
www.eastbourne.org/tourism/beachyhead/geology.php.
O'Neill, Marnie. “Dark History of Beauty Spot Where Hundreds Have Died.” NewsComAu,
News.com.au, 16 June 2018, www.news.com.au/travel/travel-updates/incidents/dark-history-of-beauty-spot-where-hundreds-have-died/news-story/27720b63cf174316ed3d479f8ca25bf0.
Shimmin, Joe. “Beachy Head.” UK Fossil Collecting, 2012,
ukfossils.co.uk/2012/01/24/beachy-head/.
stanestane. “Beachy Head.” Atlas Obscura, Atlas Obscura, 1 Sept. 2009,
www.atlasobscura.com/places/beachy-head.
Wikimedia Contributors. “Beachy Head.” Wikipedia, Wikimedia Foundation, 26 Nov. 2019,
en.wikipedia.org/wiki/Beachy_Head.
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