A History of our coast
From the red cliffs at Exmouth, to the chalk cliffs near Studland, the Jurassic Coast is a 95 mile wonder of the natural world. It’s unique too. This coastline is the only place on the planet where there is evidence from all three periods of the Mesozoic Era all in one place – the Triassic, Jurassic and Cretaceous periods of Earth’s past give us a history lesson that stretches over more than 250 million years.
Let’s start with the vividly coloured sandstone cliffs, predominantly found between Exmouth and Lyme Regis. These come from the earliest of the three periods, the Triassic, which had a hot and dry climate with vast deserts.
It’s unusual to find any fossils along this stretch of coast, but they do turn up on occasion. If you are fortunate to stumble upon a fossil, it’s likely to be between 201 and 252 million years old! This period was when the first true mammals appeared and started evolving.
The colouration of the soil can extend its thanks to the iron content it had. The iron oxidised (rusted) due to the climate, giving it the reddish colour we see today. The sandstone is soft and coastal erosion over the millennia has created some fabulous features, such as the stacks visible at Ladram Bay.
Science has shown the oxygen content of the air was 80% of what we have today. The Triassic Period was the shortest of the Mesozoic Era, spanning just 50 million years but, during in this time, a supercontinent known as Pangaea was gradually moving apart. By the late Triassic and early Jurassic, there were two separate landmasses, Laurasia to the north and Gondwana to the south.
Various climate and environment changes are believed to have caused a mass extinction event which led to the Jurassic period, which was under the rule of the dinosaurs. Whether it was volcanic eruptions, sea-level fluctuations or even seawater acidity changes, a massive event occurred, completely changing the landscape and environment.
The Jurassic period was a warm and humid time and the creation of rainforests replaced the previous deserts. The first birds appeared and the oxygen content was 130% of what we know today! Sea levels rose and tropical seas were the order of the day along our Jurassic Coast. Dinosaurs and marine reptiles were predominant and it is thought that the first flowering plants developed towards the end of the period.
The rock strata is a blue-grey colour and it’s this period that provides us with the most exciting fossils along the Jurassic Coast. Charmouth and Chapmans Pool have beautiful fossils, easily found with a gentle stroll at low tide. The Undercliffs between Seaton and Lyme Regis also show a wonderful selection of fossils as well as a fascinating view of some spectacular geology from this time.
Sealife was in abundance during this period, the climate perfect for the evolution of predators such as the Ichthyosaur and the Ammenites that we know and love as the symbol for this World Heritage Site. We also have this period to thank for the advent of petroleum-based production, aka Fossil Fuels.
Land masses continued to move and create rifts, the Atlantic Ocean started to form and after about 56 million years, we entered the Cretaceous period, the longest of the three Mesozoic periods. The 79 million year Cretaceous times provided us with the chalk cliffs we see around Beer, Seaton and at the other end of the Jurassic Coast at Old Harry Rocks. There is no obvious event that marks the change into this period, although there is evidence of a mass extinction event at the end of the period.
With 150% of the oxygen we have today, the climate was quite warm and the sea levels very high, creating many inland seas. The late Jurassic and early Cretaceous had a period of cooling with evidence of glaciers in higher latitudes but as the period continued, temperatures rose again and it is believed that it was a period of volcanic eruptions and very high carbon dioxide levels.
Bees appeared during Cretaceous times, along with other insects like ants. Plant and tree life started to spread with early figs and magnolias appearing. The chalk cliffs we see today are formed from a type of algae that was rife in the Cretaceous seas called Coccoliths.
This period ended with mass extinction events, possibly from asteroid impacts and volcanic activity which blocked the sun and reduced photosynthesis. There is another school of thought that believes it was a gradual shift in climate and sea levels, perhaps similar to what we are experiencing now?
Throughout these three periods, the land moved, rose, dropped and thus created the coastline we see today. There is a great ‘fault’ at Seaton Hole where one can see a transition between the Triassic and Cretaceous. The Jurassic period appears to be missing here, although just a mile or so to the east, it pops back up again.
Our planet is forever changing. From its formation 4500 million years ago, it has evolved and altered and humans have only been here for a very short time. The earliest Homo Sapien remains have only been dated to 200,000 years old (more on this subject in part 2). Isn’t it mind-boggling to think that the Jurassic Coast is up to 252 million years old?
When you consider how much we have achieved, and destroyed, in the relatively short time we’ve existed, it’s still obvious that we are just the merest speck of dust on the planetary clock.
Humbling isn’t it?
History of the Jurassic Coast Part 2. Written by Roy Beal
This time we shall look at the more modern history of the Jurassic Coast. ’Modern’ is a loose term as we shall start with the end of the Cretaceous Period and look at the main events (and some interesting history) that have happened up to the present day. So in a rough, perhaps vague, chronological order, let’s begin.
The Cretaceous period ended around 66 million years ago and a lot has happened since then. Mass-extinction events occurred, the planet changed as land masses moved and as things started to settle and the climate changed, we entered the Cenozoic Era, starting with the Tertiary Period.
This period is when the rise of the mammals began and, after the best part of 64 million years, the earliest Humans evolved. A 3.2 million-year-old Australopithecus skeleton, named Lucy, was discovered in 1974 by palaeontologist Donald C. Johanson in Ethiopia. Lucy is one of the earliest remains of human ancestry ever found, certainly the most famous. The skeleton is about 40% complete and indicates a mixture of ape and human. With long dangling arms but an ability to walk upright, little Lucy was about three and a half feet tall (107cm).
Scientists believe our first ancestors appeared between five and seven million ago, which was when ape-like creatures first started to primarily walk on two legs. There were a few species, Homoerectus (Upright Man) in Africa and Homo neanderthalenis (Neanderthal) in Europe for example. Around 200,000 years ago, our lineage, Homo sapien – Wise man, first appeared in Africa and we started migrating at least 100,000 years ago, one advantage of having an ability to walk great distances on just two legs and a desire to explore, something that hasn’t changed to this day. We may not have looked too different from the other species but the H. sapien was very intelligent in comparison.
Within a few thousand years of ‘first contact’ between the other species and us, they went extinct and by about 40,000 years ago, the only remaining human species left on Earth was us. One gets the feeling that we are destined to consume and destroy – it’s just in our nature.
By the time all this happened, we were now well into the Quaternary Period, which started 2.5 million years ago and is where we are today. We’ve survived ice ages and the evolution of our kind, we created the principle of civilisation and we’ve taken over the planet, perhaps not in the best way.
The geology of the Jurassic Coast is perhaps the finest in the world. There are many fabulous rock formations and features along the Jurassic Coast. One of the most famous is Lulworth Cove, a natural harbour that is almost a perfect circle. Its formation started about 10,000 years ago when meltwater from the end of the last ice age, along with rising sea levels, eroded the cliffs, finding a way through. Then, thanks to wave diffraction, the cove that we see today formed as the softer clays were worn away. Nearby is Stair Hole, a naturally forming cove that possibly shows what Lulworth Cove may have looked like as it was being born.
The last 10,000 years was an important time for our Jurassic Coast. Sitting on the 350 mile long English Channel, the southern coast of England is subject to fast tidal flows and the Atlantic weather. Formed roughly 9000 years when the last remnants of the Ice Age melted, the English Channel has a history that is vast and exciting. Once connected to mainland Europe via a land-bridge, we are now an island nation and the English Channel is our protector. From Roman invasion and Viking pillaging, the story of The Channel would take up a whole book on its own, with ease.
The most westerly point is Land’s End and is at its narrowest in the Strait of Dover, just 21 miles wide. The easterly point is St. Margaret’s at Cliffe, near Dover. It’s unique location, separating Britain from mainland Europe, generates some very complex tides, partly due to the narrow width and partly because the Atlantic and the North Sea meet in it too. It’s one of the busiest waterways in the world. Not just the cross channel traffic connecting Europe and Britain, but also the Scandinavian and Russian shipping that wants to get to the Atlantic without travelling around the tip of Scotland.
Chesil Beach started to form around the time of the birth of the English Channel. The vast 18-mile long shingle bank was created thanks to something called Longshore Drift. This is the effect of wave action pushing pebbles and stones along the coast and, with Chesil Bank, the smaller pebbles have remained at the western end, increasing in size to the rocks found at Chesil Cove to the east. Rising up to 50 feet high (15 metres) and 660 feet wide (200 metres), it is both a marvel of nature and, when kayaked, a boring featureless view until you reach the Abbotsbury Sub-Tropical gardens.
Old Harry has been a resident of the Jurassic Coast for many years. Sitting on the Purbeck Coast, this chalk stack, formed over many years, once had a partner that suffered at the mercy of the sea and collapsed in 1896. Erosion is forming a new smaller stack, now known as Old Harry’s Wife.
The stacks formed through erosion and hydraulic action. Air and water would have been forced through cracks in the cliffs, eventually forming caves and then arches. Over time the arches collapsed, leaving the stacks we see today. Old Harry is believed to have been named after the Devil that, legend has it, used to sleep on the rocks.
There are similar stacks at the other end of the Jurassic Coast at Ladram Bay. These are formed from the sandstone cliffs.
The first known settlement along this coastline was by Mesolithic hunters. This civilisation would have arrived from Europe around 12500 BC, before the channel formed, crossing a land-bridge. They would have used stone tools and would possibly have been introduced to farming as they moved into the Neolithic era when more immigrants from Europe arrived. This time in history is known as The Stone Age and it’s likely that this is when humans started to permanently or seasonally inhabit settlements for farming. Around 4500 BC, we moved into the Chalcolithic (Copper Age) era and the start of metallurgy leading us into the Bronze and Iron ages (a copper axe has been found in Serbia which would indicate some Europeans were using metals as early as 5500 BC). By the end of the Iron Age (around 500BC in northern Europe), humans were beginning to practice Historiography, the method of developing history as an academic discipline.
In 1348, the Black Death arrived in England. A bubonic plague that was believed to have been spread by flea-infested rats had its first known case when a seaman arrived at Weymouth in June that year. By the Autumn, it had reached as far as London and by the time it started to die down in December the following year, 40-60 percent of the population was believed to have been lost. The plague came and went over the next few hundred years, with the last known outbreak occurring in London during 1665-66.
The Great Storm appeared on November 22nd 1824 and the Jurassic Coast took a massive hit from nature’s full fury, with hurricane-force winds and a storm surge that caused a lot of damage. Houses along the esplanade at Sidmouth were destroyed, as was the Esplanade at Weymouth, along with mass flooding through various seafront houses. The streets also had many boats drifting along too. 90 metres of The Cobb at Lyme Regis was badly damaged and Fleet and Chiswell villages were almost destroyed too when the storm surge topped Chesil Bank. 30 lives were lost in Chiswell alone, along with the destruction of eighty houses. The village never fully recovered.
There is oil on the Jurassic Coast. Fossil Fuel as it is known can be found at Kimmeridge. A ‘Nodding Donkey’ oil pump tirelessly works away and pumps around 60 barrels of oil day. The Famous Burning cliffs near Ringstead are an example of a naturally occurring phenomenon. The most famous example is a landslip in 1826. This caused trapped oil and gas to ignite, which burned for three years! As recently as 2000, there have been cliff fires caused by landslips and the shale igniting.
Sitting where it is, the Jurassic Coast gets the brunt of the prevailing South Westerly weather. Erosion is forever unveiling new fossils and features and, over time, the sea is gradually reclaiming the land. With famous landslides over the years, the coastline is an evolving and living thing. Regular cliff falls occur and the general public should always be mindful of any warning signs.
There have been some large landslips over the years and one of the most famous was the Great Slip of 1839. Between Seaton and Lyme Regis, a massive area of land slipped on Christmas Day and created what we now call The Undercliffs. At the time of this slip, it initially created a natural harbour that the military looked at as a possible base, but it was washed away over the next few months. The landslip also created Goat Island. A piece of farmland that separated from the mainland but the 15 acres of corn and turnips were still able to be harvested the following year. In all, 50 acres of farmland were lost in the collapse.
In the days leading up to this event, locals had been aware the land had shifted. One resident even noticed that his front door was difficult to close the evening before.
There had been a lot of rainfall in the weeks prior to the event and when the cliffs collapsed, locals initially believed there was an earthquake such was the noise and movement of the ground.
It became such big news that even Queen Victoria visited the area to take a look, sailing there in her royal yacht.
Another famous landslip is the Hooken Slip between Beer and Branscombe in 1790. This occurred overnight when 15 million tons of chalk and greensand cliffs collapsed. Evidence is still visible today and best seen from a kayak.
There is a famous horse along this coast. The Osmington White Horse was cut into the limestone of hillside of Osmington Hill in 1808. King George III was a regular visitor to the area and it is said that as this depiction of him on his horse shows him leaving the area, he was very offended and never returned!
The great ‘seaside holiday’ possibly started in the Georgian era of the 1700s. The gentry and aristocracy believed that sea water was a great healer (I believe it is too!) and seaside resorts started to gain popularity among the well-to-do. By the time of the railways in the 1800s, Victorian life was such that seaside holidays truly flourished and even the less well-to-do found these holidays were affordable as well.
The present day Jurassic Coast is a popular tourist destination, great for the local economy but, perhaps, not so great for the environment. Along with the natural erosion caused by the sea and the weather, the beaches and cliff paths are prone to damage from footfall and littering. We need to be mindful of this and take great care when out and about. If you happen to be exploring the coast path, the beaches or even just a side street in one of the many Gateway Towns, please pick up a few pieces of litter and help us make a difference.
Thanks for reading and if you would like to join us on some litter picking adventures, just use the ‘Contact us’ button on the homepage.
Roy Beal.