Category: Geology

Notes on Lyme Regis

A Private Fossil Walk Represents Good Value

With the completion of the eastern sea wall at Lyme Regis last year the access to the beach between the town and Charmouth has certainly got easier.  No more climbing over the slippery rocks and the groynes that laid between the end of the beach front and the Church Cliffs.  That might sound like good news and it certainly is, especially for families trying to access the beach.  There is a downside to the new sea defences though, greater access has meant that over the summer months there have been more people than ever scouring the beach between Charmouth and Lyme Regis looking for fossils.  Pickings can be somewhat slim as a result.

The Newly Completed Magnificent Sea Wall at Lyme Regis

Part of the coastal defences at Lyme Regis

Part of the coastal defences at Lyme Regis

Picture Credit: Everything Dinosaur

The sea wall is part of an extensive array of features to help secure the cliffs and the land immediately behind them in a bid to protect the area from further land slips.  Eventually, these defences will give way but the engineering works has probably given the many houses on the cliffs another fifty years of life or so.  Whether or not the sea wall and other defences such as the remodelled beach area close to the famous Cobb has had an impact on the way in which the waves scour the beaches remains uncertain, time will tell, although we have heard from one reliable source that there seems to be a greater amount of sediment deposited out into Lyme Bay.  To help stabilise the cliffs, the slopes have been planted with thousands of small bushes and other plants to help anchor the soil.

The Cliffs have been Planted to Help Prevent Further Land Slides

Stonebarrow and Golden Cap can be seen in the background.

Stonebarrow and Golden Cap can be seen in the background.

Picture Credit: Everything Dinosaur

What Do the Changes Mean for Fossil Hunters?

Lyme Regis has always been a popular destination for would-be fossil hunters. With easier access to the beaches to the east of the town, there is a feeling amongst locals that finding fossils along the shoreline is getting harder.  There are certainly lots of fossils to be found, but large pieces of ammonite and any Ichthyosaur vertebrae are increasingly rare.  For example, during a recent trip to Lyme Regis, we spent a morning on the beach walking slowly up to Charmouth and we were surprised by the lack of fossils.  Belemnite guards were still plentiful, especially as we approached the “Belemnite Beds” but we found no fossils of Promicroceras, which surprised us somewhat.  This small ammonite used to be a relatively common fossil find, there was also a lack of nodules on the beach, although from the scattered shards of split rock there was plenty of evidence of previous visitors having hammered away quite happily at any stone bigger than a house brick, whether or not it was likely to contain a specimen inside.

Not a Very Successful Fossil Hunt

Fossils are becoming more difficult to find at Lyme Regis.

Fossils are becoming more difficult to find at Lyme Regis.

Picture Credit: Everything Dinosaur

Advice for Visitors to Lyme Regis

With the popularity of fossil collecting on the increase and with the easier access to the beach, visitors to Lyme Regis might be disappointed by their lack of fossil discoveries.  One way of helping to get the most out of a visit is to book yourself onto an organised public walk.  There are a number of professional fossil hunters and guides who offer public walks.  These are a very good idea, especially when one considers the risk of getting cut off by an incoming tide or the hazards of rocks falling from the cliffs.  On a public walk your knowledgeable guide should be able to provide you with a very informative tour of the geology and help you to find a few fossils along the way.

Private Fossil Walks are Best

However, if you really want to make the best use of your time, try booking a private walk.  On some public walks that we have observed there can be as many as fifty people in the party.  Simply, getting a question answered amongst a throng of eager fossil hunters that size can be quite an ordeal, even the most dedicated guide can struggle to accommodate everybody’s needs.  Public walks tend to take place on the weekend, a time when the beaches are likely to be congested.  Private walks can be booked at a time to suit you (tides permitting) and you can be assured that your party will be very well looked after by the guide.  You are also more likely to be directed to the best fossil hunting locations, local knowledge wins out every time.  For example, for that beautiful Promicroceras ammonite, your best chance might be to sieve for fossils.  On a private walk, the guide can provide suitable sieves and show you the best technique to help you make your very own fossil discovery.  Knowing exactly where to start sieving on the beach is half the battle.

Still Fossils to be Found but Local Knowledge is Key

Fossils can still be found on the shore.

Fossils can still be found on the shore.

Picture Credit: Everything Dinosaur

Private walks book up very quickly in advance, if you are thinking of visiting the Dorset coast next year, now is an ideal time to get yourself and your family booked on one.  Fossil walks are arranged around safe tide times so be aware that some preferred days may not be suitable.  Most organisers of private fossil walks ask for children to be at least five years old.  Walks take around three to four hours, advice can be provided on where to park any vehicles and as for what you should bring here is a quick check list:

  • Suitable clothing, wellington boots or other stout footwear.  Warm clothing especially in the winter and early spring, having  a waterproof jacket on hand is very sensible, gloves in cold weather too.
  • Bring a snack and a drink although remember to take your rubbish home with you.
  • Bathroom breaks – there are no toilet facilities on the beaches, although most walks commence from the town centre and there are toilet facilities here at the start of the walk.
  • Tools to bring – most guides will be happy to break any nodules open for you, hammers are not usually supplied.  If you do bring your own hammer (please make sure it is a geological hammer), then remember the safety specs and tough gardening gloves.  For advice on the difference between geological hammers and tool box hammers: Geological Hammers What’s So Special About Them?

The fossil walk guide will be able to provide you with the very best chance of finding a top quality fossil and also be able to point out the best places to look.  You will learn a lot more about the history of the local area as well as having the opportunity to get one to one assistance and support.  Private fossil walks really do offer excellent value and they usually cost less than a family three-course meal in a pub.

For further information on private walks (public walks as well), Everything Dinosaur recommends: Lyme Regis Fossil Walks (Public and Private)

Private fossil hunting walks at Lyme Regis can prove to be a very worthwhile investment and provide visitors to the Jurassic Coast with an excellent opportunity to learn more about this fascinating area of Britain.

Out of Africa and Into Arabia

A New Look at the Spread of Modern Humans

A team of international scientists from a variety of disciplines have pooled their skills and shed light on the role of the Arabian Peninsula in the migration of our species out of Africa.  A migration that was to eventually lead to human beings (Homo sapiens) spreading to every continent on the planet.  A consequence of this exodus may have been the extinction of other types of hominins such as the Neanderthals and the Denisovans.

Although the Kingdom of Saudi Arabia is very arid today and much of the country is classified as desert, back in the Pleistocene Epoch, it looked very different.  Palaeontologists have been working with archaeologists, cartographers and experts in geochronology helping to map the ancient landscape of the peninsula.  It turns out that much of Arabia was once a lush and fertile land teeming with game and with plenty of navigable rivers for our ancestors to exploit.

This the first time, such a group of technical experts have worked together to plot the palaeoenvironment of this part of the world.  It seems that the Arabian Peninsula was not just a stopping over point for human migration, but this now largely arid landscape once offered hunter/gatherers rich pickings indeed.

The head of the Saudi Commission for Tourism and National Heritage, Prince Sultan bin Salman bin Abdulaziz explained that this new study suggests that the Arabian Peninsula had human settlements for long periods of time and that it was not just merely a transit point, as was previously thought by many anthropologists and other scientists.

He stated:

“The Arabian Peninsula has witnessed dramatic changes in climate.  In the middle Pleistocene this encouraged early man to make for the then-green peninsula as his destination.”

Green Arabia – Scientists Have Identified a Number of Ancient Lakes and River Systems

A green and pleasant land.

A green and pleasant land.

Picture Credit: Crassard et al. 2013

Two main human migration routes have been identified from Africa to Arabia.  The first was a northern route via the Nile Delta into Arabia from what was to become Egypt.  The second route is much further south and involved early humans crossing over from the horn of Africa.  The multi-disciplinary team have put together a picture of an Arabian environment that has changed much in the last few hundred thousand years.  Over 10,000 ancient lakes have been identified including a number in what is now the barren Nafud desert.  These findings are supported by fossil evidence as the palaeontologists have found the fossilised remains of hippos, elephants, shellfish and crocodiles.

Although the climate has changed over time, the researchers also identified several settled, stable periods during the Pleistocene when the climate was humid with reliable rainfall.

The Limestone Fossils of Dudley (Wrens Nest)

Visit to the Wrens Nest Nature Reserve (Dudley, West Midlands)

Prior to the first of Everything Dinosaur’s summer schools just time for team members to take in a quick trip to the famous Wrens Nest National Nature Reserve (Dudley, West Midlands).  It was an early start, (yet again), but it did prove worth it as the weather behaved and team members were able to enjoy a walk around this very significant part of the world (in terms of geology anyway), before having a picnic close to the famous Silurian ripple beds.  The Silurian ripple beds are just one of the amazing geological features to be found in this abandoned quarry.  The area was declared a National Nature Reserve back in 1956 due to the amazing fossil assemblage that can be found over the 100 acres or so of the Reserve.  Some seven hundred different invertebrate fossils have been identified at the site, they date from the Silurian age (approximately 423 million  years ago), the rocks themselves being part of the Wenlock Group.  Eighty-six of the fossil types are unique to Dudley, they have been found nowhere else in the world.

The Amazing Ripple Beds of Wrens Nest

Amazing geological feature.

Amazing geological feature.

Picture Credit: Everything Dinosaur

A Close up of the Silurian-aged Ripple Beds of Wrens Nest National Nature Reserve

Preseved in limestone, the ripple beds.

Preserved in limestone, the ripple beds.

Picture Credit: Everything Dinosaur

The quarry work ended in 1925 and when the Reserve was created it was the UK’s first ever geological National Nature Reserve.  It the area has also SSSI (Site of Special Scientific Interest) status due to its geological, palaeontological and historical significance.  It is also home to a wide variety of wild flowers and the caverns, now barricaded to prevent human visitors provide invaluable overwintering habitats for a number of species of bats.

Although this picturesque nature reserve is enjoyed by local residents and visitors alike, it is the huge variety of invertebrate fossils that amazes team members.  Whilst we enjoyed our picnic (taking great care to remove all our litter), we marvelled at the array of fossils that can be found eroding out of the limestone beds (no hammers allowed).  We contented ourselves by taking some pictures of the rich fossil assemblage, fossils to be found at this location include corals (tabulate and rugose forms), crinoids (sea lilies), brachiopods, bivalves, gastropods and some trace fossils (worm tubes).  Sadly, the trilobite fossils that made this part of the world so famous are increasingly rare.

A Close up of the Amazing, Highly Fossiliferous Limestone at Wrens Nest

A huge variety of fossils can be found.

A huge variety of fossils can be found.

Picture Credit: Everything Dinosaur

The exposed rock faces of the various quarry sites give geologists a unique opportunity to teach Silurian geology to students in an outdoor setting.  The location provides a definitive section through the Wenlock Formation.  The town of Dudley, is synonymous with the Wenlock limestone strata and the fossil assemblage contained therein.  This internationally famous location has provided a valuable insight into the marine life in coral sea environments during the Late Silurian geological period.  Both macro and micro-fossils have been preserved at this site.

Everything Dinosaur team members certainly enjoyed their visit to the fossil rich Wrens Nest National Nature Reserve to celebrate the tenth anniversary of the company.

Earth’s Magnetic Shield is Older than Previously Thought

Plate Tectonics Got Started Early in our Planet’s History

Our planet has a magnetic field, similar to the magnetic field that can be generated by a simple bar magnet.  This field is aligned close to but not directly with the Earth’s axis of rotation.  The magnetic poles lie some way from the geographic poles (separated by approximately eleven degrees).  Earth’s magnetism is powered by fluid motion inside our planet and this field protects all life from the harmful solar winds that are expelled by the sun.  When this field was first generated has remained a mystery.  It had been thought that the Earth’s magnetic field had been around for some 3.45 billion years, now new research conducted by scientists at the University of Rochester (New York) suggests that this magnetic field is actually much older.

John Tarduno, a geophysicist at the University of Rochester and lead author of a paper published in the journal “Science” estimates that the Earth’s magnetic field was formed at least four billion years ago.  This is much earlier in our planet’s history than previously thought, it is estimated that Earth was formed some 4.56 billion years ago.

Since 2010, the best estimate of the age of Earth’s magnetic field has been 3.45 billion years. But now a researcher responsible for that finding has new data showing the magnetic field is far older.

Why is a Magnetic Field Important?

It has to do with our sun and cosmic radiation.  As well as visible light, the sun sends out streams of charged particles into space, it is not the only source of cosmic radiation, any luminous body in the universe produces radiation, but since the sun is 93 million miles away, at the centre of our solar system and with a radius of approximately 700,000 kilometres it is the biggest contributor to the harmful cosmic rays that get sent our way.  Particles of different wavelengths and energies are being generated all the time by our sun and it is these higher energy radioactive particles that are dangerous to life forms.  Thankfully, those that make it to Earth are deflected away by our planet’s strong magnetic field.  This magnetism acts as a shield helping to protect our planet and the life that exists on it.

An Artist’s Illustration of the Earth’s Magnetic Field Deflecting Particles

Helping to keep our planet habitable.

Helping to keep our planet habitable.

Picture Credit: Michael Osadciw/University of Rochester

Professor Tarduno explained:

“A strong magnetic field provides a shield for the atmosphere.  This is important for the preservation of habitable conditions on Earth.”

This life saving magnetic field is also responsible for producing the Aurorae (northern lights – Aurora Borealis and southern lights Aurora Australis), spectacular light shows that are created when the solar wind and its charged particles interacts with our planet’s magnetic field and atmosphere.  As these particles approach Earth, they distort our magnetic field and allow some charged, high energy particles to enter our atmosphere at the magnetic north and south poles.  These charged particles interact with gases in our atmosphere and “excite” the gas particles which in turn glow, just like the gas in a florescent tube light you might have in your kitchen.

A Spectacular Light Show (Northern Lights Seen in North Yorkshire)

Aurora Borealis seen in northern England.

Aurora Borealis seen in northern England.

Picture Credit: Owen Humphreys/PA

Our planets magnetism is generated in its liquid iron core.  It acts as a “geodynamo” and requires regular releases of heat from our planet to function.  This heat release is aided by plate movements at the Earth’s crust.  Convection allows the transfer of heat from the interior to our planet’s surface, but the origin of our tectonic plates is contentious, with many physicists suggesting that our planet lacked a magnetic field for more than a billion years after it was formed.

A study of the mineral magnetite found within zircon crystals collected from the ancient rocks of the Jack Hills of Western Australia has helped the Rochester University to determine that the Earth’s magnetic field is older than previously thought at around 4 billion years of age.

Magnetite is a naturally occurring magnetic iron oxide, it locks in information about the Earth’s magnetic field as it cools and forms from its molten state.  The ancient rock deposits of the Jack Hills represent some of the oldest strata on our planet and zircons from these rocks have already been used to help determine how quickly the Earth cooled after its initial formation.

To read more about this 2014 study by scientists from the University of Wisconsin- Madison: The Earth Cooled Earlier Than Previously Estimated

In order for the team to get reliable, accurate results, it was crucial that the minerals remained unchanged over the vast period of time since their formation.  Professor Tarduno’s study of the magnetic field strength preserved inside the pristine zircon crystals has enabled the team to build up a picture of the Earth’s magnetic field over time.  The microscopic zircons were analysed using a superconducting, quantum interference device, which is unique to the University, the sensitive instrument (called a SQUID magnetometer), showed that the intensity measurements recorded in the samples were indeed as old as four billion years.

Implications for Life on Earth and Other Planets

The intensity measurements reveal information about the presence of a “geodynamo” at the Earth’s core.  Tarduno explained that solar winds could interact with the Earth’s atmosphere to create a small magnetic field, even in the absence of this core dynamo.  Under those circumstances, it has been calculated that the maximum strength of a magnetic field would be 0.6 μT (micro-Teslas).  The values measured by Professor Tarduno and his colleagues were much higher than 0.6 μT, suggesting the presence of a “geodynamo” at the planet’s core, as well as indicating the existence of the active plate tectonics needed to release the built-up heat.

Professor Tarduno added:

“There has been no consensus among scientists on when plate tectonics began.  Our measurements, however, support some previous geochemical measurements on ancient zircons that suggest an age of 4.4 billon years.”

Four billion years ago, our sun was much younger and it was sending out much more powerful solar winds which were up to a hundred times stronger than today’s.  In the absence of this nascent magnetic field the high energy particles that make up the solar wind would have ionised and blasted away light elements (those with a relatively low atomic mass), from the atmosphere, elements such as hydrogen, nitrogen, carbon and oxygen.  The loss of these elements would have made the evolution of complex life on our planet almost impossible (probably completely impossible).

Our planet, may have come to resemble that of our second nearest planetary neighbour, Mars.  Mars is approximately half the size of Earth, the mass of Mars is around ten percent of the Earth, it may once have had an active “geodynamo” for a time after its formation, but due to the planet’s size, this active, convectional dynamo seems to have run out of energy and ceased.  This led to the Red Planet losing any magnetic field that it had.  The atmosphere was blasted away by the solar wind.  Today, scientists are confident that Mars once had liquid water but it is likely that this water was driven off along with most of the light elements in the atmosphere and on the surface of the planet.

Professor Tarduno believes that the loss of the “geodynamo” dramatically altered the history of Mars.  He stated:

“It may also be a major reason why Mars was unable to sustain life.”

Mars does have an atmosphere, it consists of nitrogen and carbon dioxide but it is just one percent the thickness of our own planet’s atmosphere.  Unmanned, robotic vehicles like the Mars Rover may have provided us with evidence that Mars may once have had vast amounts of liquid water – so much water in fact that there is evidence of global scale floods on its barren, rocky surface.

It seems we have a lot to be grateful for when it comes to our magnetic field and its early establishment may have assisted in the development of life on our own planet.

Dinosaur and Science Speed Stacking Memory Game (Key Stages 3 and 4)

Speed Stacking Memory Game – Science Learning (Key Stages 3 and 4)

With a greater emphasis on factual recall enshrined within the new national curriculum here’s a simple idea to help young scientists remember terms and sequences as part of their science studies.  Create a fun speed stacking memory game that will help pupils to memorise key points and key items of information.  This idea can be modified to fit all sorts of teaching objectives and best of all, it gives teachers and home educationalists a wonderful opportunity to introduce how data can be plotted and shown visually.

Dinosaurs and Science Speed Stacking Game

Simple memory game to help young scientists.

Simple memory game to help young scientists.

Picture Credit: Everything Dinosaur


  • Plastic cups (raid the water cooler)!
  • Sheet of labels (Everything Dinosaur supplies various sets of labels – size of dinosaurs, sorting out geological periods and for older students, Linnaean hierarchy labels on the “dinosaurs for schools” website).
  • Sticky tape to secure labels to the bottom of the plastic cups.
  • A stop watch or other timing device (Ipad, Smart phone and so forth).

To access the free, downloadable Everything Dinosaur school resources: Dinosaurs for School Website visit the downloads section for the free, teaching and educational resources.

Let’s imagine that you have to explain about deep time and the geological periods as part of the teaching involved at Key Stage Three (genetics and evolution).  To help reinforce learning, challenge the students to create a stack of plastic cups in the correct geological order, mapping out the fossil record of visible life.  Just stick labels to the bottom of the cups – Cambrian, Cretaceous, Jurassic and so forth and once having explained about geological time challenge the class to stack the cups in the correct order in the fastest possible time.  As an extension you can plot the results and the class to work out the best way to make a visual representation of the data – bar charts, line graphs perhaps?

Handy Labels for the Speed Stacking Game?

Learn how animals are classified, learn the geological timescale with this speed stacking game.

Learn how animals are classified, learn the geological timescale with this speed stacking game.

Picture Credit: Everything Dinosaur

Perhaps, you are working with Key Stage 4 and you are covering how changes in biology have led to a better understanding of the process of evolution.  You want to explain how life is classified and introduce Linnaean classification, from a Domain down to a Species a simple stacking game can help to reinforce learning and to introduce a fun element into the lesson plan.  Record how long it takes each student to stack the cups in the correct sequence.  As an extension, can the class calculate the mean, mode and median stacking times?

Getting to Grips with Scientific Classification

Just add the labels to the plastic cups to make a fun memory game.

Just add the labels to the plastic cups to make a fun memory game.

Picture Credit: Everything Dinosaur

This is a very simple but effective science speed stacking game.  It is great for helping students to memorise terms and sequences such as geological periods.  Lots of different labels can be created, perhaps even leading to the development of a dinosaur themed speed stacking game.

Extension Ideas

  • Challenge the students to create the best way of visually displaying the data
  • Can the class calculate the mode, median and mean
  • Plot a distribution curve of the timing results, what are the variances?
  • Can the students devise science themed speed stacking games of their own?

For prehistoric animal themed teaching resources including model kits, crafts and real fossils: Dinosaur Teaching Resources

Take Care When Fossil Hunting on the “Jurassic Coast”

Warning Issued to Holiday Makers

Dorset is one of the prettiest and most majestic of all the English counties.  This summer, there are going to huge numbers of holidaymakers heading down to England’s “Jurassic Coast” and we expect there are going to be great many visitors to picturesque Lyme Regis.  However, as the school holidays have started, we at Everything Dinosaur, think it appropriate to issue a warning about straying too close to the cliffs that occur along the Dorset and Devon coast.

Beautiful Charmouth and Lyme Regis – Very Popular Holiday Destinations

Photograph taken in 2009.

Photograph taken in 2009.

Picture Credit: Everything Dinosaur

Many locals tell us that this part of the world has its own “mini climate”, it most certainly has lots of sunshine and there is always plenty to do and see in this, in our opinion, one of the most attractive parts of southern England, but we would advise visitors to the beach, especially would-be fossil hunters in the Lyme Regis and Charmouth areas to steer well clear of the cliffs. Rock falls and mudslides are very common and sadly serious accidents and even fatalities can occur.

On July 25th 2012, Everything Dinosaur reported on a fatal incident that occurred at Hive Beach, near Bridport just a few miles east of Charmouth.   Last month, we reported on another landslide fatality, this time from the popular Llanwit Major area of South Wales, another favourite location with fossil hunters.

To read more about this tragic event: Woman Killed by Rock Fall at Popular Fossil Hunting Site in Wales

Whilst areas such as the famous “Ammonite Pavement” that can be seen to the west of the town (Lyme Regis), is located quite far from the cliffs, any rocks and other material that fall are likely to travel quite a distance so it is sensible to heed the advice of locals and ensure that you are a safe distance away from any hazards.  It is also good advice to familiarise yourself with the tide times.  As landslides have altered the shape of the coastline it is all too easy to find yourself getting cut off during an incoming tide.  Everything Dinosaur team members advise always go fossil hunting at a beach location on an outgoing tide.  With so many fossils to be found at Lyme Regis and Charmouth along the foreshore, there is no need to approach the cliffs and a lot of fun can be had searching along the shoreline for fossils in a couple of hours or so as the tide recedes.

Lots of Fossils to Spot Away from the Jurassic Coast Cliffs

A big fossil close to the Ammonite Pavement.

A big fossil close to the Ammonite Pavement.

Picture Credit: Everything Dinosaur

 Lyme Regis fossil expert Brandon Lennon commented that there was glorious weather in the Lyme Bay area yesterday, but today, (Sunday), there was quite a gale blowing.  Despite this, large numbers of tourists were on the beach and many of them were too close to the cliffs.

Brandon said:

“People are right up under the cliffs looking for fossils and they should definitely not do this as it is incredibly dangerous.  I think it is going to be very busy in Lyme Regis this summer, even with the occasional little bit of bad weather at times.”

With the popularity of the film “Jurassic World”, the Lyme Regis area can expect record numbers of fossil hunters to visit the area over the summer, but just like Brandon, we advise visitors to the beaches to take care and heed any council notices.

Brandon conducts organised fossil hunting walks and these are a great way to go fossil hunting safely as well as learning about the amazing local geology.  These walks take place on Saturdays, Sundays and Mondays and private bookings can also be made, to learn more about organised, conducted fossil hunting tours: Lyme Regis Fossil Walks

 The Amazing Ammonite Pavement (Monmouth Beach)

Falling tides reveal the extensive Ammonite Pavement sometimes referred to as the Ammonite Graveyard.

Falling tides reveal the extensive Ammonite Pavement sometimes referred to as the Ammonite Graveyard.

Picture Credit: Everything Dinosaur

A spokesperson from Everything Dinosaur stated:

“Whilst fossil hunting can be a very enjoyable experience for families, we do urge all visitors to take great care when visiting locations such as Charmouth and Lyme Regis.  Landslides are a very common occurrence and going fossil collecting with an expert is a sensible option.”

Extreme Equatorial Climates Slowed the Rise of the Dinosaurs

Climate of the Tropics too Unstable for the Dinosaurs to Dominant in the Late Triassic

The vast majority of the reptile species found today are confined to the tropics.  However, a new study undertaken by an international team of researchers suggests that during the Late Triassic as one group of reptiles came to dominate the land, the dinosaurs, they struggled to gain a foothold in the tropics due to extreme climate fluctuations.  Dramatic swings in the equatorial climate from wet and humid to extremely hot and dry checked the evolutionary development of the Dinosauria.  Such conditions may be repeated in equatorial regions in the very near future due to increased amounts of carbon dioxide in the atmosphere as a result of global warming.  What slowed the rise of the dinosaurs, could provide our species Homo sapiens with a viable model of what lies in store for us.

The Flora and Fauna of the Late Triassic (Ghost Ranch, New Mexico)

Dramatic climate changes from very wet to very dry conditions limited the range of large, herbivorous dinosaurs.

Dramatic climate changes from very wet to very dry conditions limited the range of large, herbivorous dinosaurs.

Picture Credit: Victor Leshyk

The picture above shows a typical scene representing the flora and fauna of the Late Triassic (Ghost Ranch, New Mexico).  Thick forests of primitive ,drought resistant conifers, araucaria, redwoods and podocarps dominate the landscape.  Armoured Aetosaurs (foreground and background) would have grazed upon ferns, club mosses and horsetails, whilst Phytosaurs, which superficially resemble modern-day crocodiles, would have hunted small animals and mammal-like reptiles.  The vast majority of dinosaur fossils associated with the Ghost Ranch location (Chinle Formation), relate to small, Theropod dinosaurs.

Late Triassic Equatorial Dinosaur Puzzle

What has troubled the curiosity of palaeontologists, is why so very little evidence of larger plant-eating dinosaurs have been found in rock formations that represent deposits laid down close to the Equator?  The first dinosaurs might have evolved some 240 million years ago, perhaps slightly earlier.  Although, the fossil record is far from complete, it is likely the first dinosaurs lived in the southern hemisphere.  Over the next thirty million years or so, the Dinosauria gradually diversified and spread.  At this time in our planet’s history, most of the landmasses were joined together to form a single, super-sized land mass (Pangaea or Pangea).  Fossils of Sauropodomorphs have been found in Late Triassic strata from northerly as well as southerly latitudes but very few fossils of big, herbivorous dinosaurs have been found from locations that would have been close to the Equator.  Small-bodied, meat-eaters are found, although they do not make up a huge proportion of the total fauna, least not until the latter stages of the Triassic, but there is very little evidence to suggest the presence of large, plant-eating Sauropodomorphs.

To read about the recent discovery of a new type of meat-eating, Therpod dinosaur from the south-western United States: New Theropod Dinosaur Discovery Provides Evidence of Meat-Eating Dinosaur Diversification

A Map of the World in the Late Triassic

The position of the continents during the Late Triassic.

The position of the continents during the Late Triassic.

Picture Credit: North Arizona University with additional annotations by Everything Dinosaur

The map shows the approximate location of the Ghost Ranch site (New Mexico, USA), which during the Late Triassic lay close to the Equator.

To help understand the why certain types of dinosaur may have struggled to survive in the tropics, an international team of scientists, including researchers from the University of Southampton, have created a remarkably detailed picture of the ecology and climate of the famous Ghost Ranch fossil site (New Mexico).  The colourful rock layers preserved in this part of south-western United States represent a series of continental deposits, consisting mainly of sandstones and shales.  They date mostly from the Late Triassic (Carnian and Norian faunal stages).  The research team sampled different layers and used these samples to identify microscopic trace fossils such as plant pollen and fern spores.  This provided the researchers with some understanding of the changing plant populations over time.  This data was correlated with the work of organic geochemist Jessica Whiteside (Southampton University), who analysed carbon isotopes preserved in the rocks. Dr. Whiteside identified repeated highs and lows in the amount of “heavy” carbon-13 that was recorded, signs of major changes in the ecology of the area over time.  These peaks and troughs lined up with changes in the composition of the fossil pollen and fern spores preserved  This suggests that there were wild and dramatic climate swings leading to a flipping of floras, between a dominance of water loving species suited to a humid, warm and wet environment and those species that thrived when the climate became much more arid.

Dr. Whiteside Taking Samples for Isotope Analysis

Researchers Jessica Whiteside and Maria Dunlavey taking rock samples for analysis of the isotopic signature of organic carbon at Ghost Ranch, New Mexico. These data help reconstruct ecosystem productivity and environmental changes in the Triassic.

Researchers Jessica Whiteside and Maria Dunlavey taking rock samples for analysis of the isotopic signature of organic carbon at Ghost Ranch, New Mexico. These data help reconstruct ecosystem productivity and environmental changes in the Triassic.

Picture Credit: Randall Irmis

Commenting on the implications of this part of the study, Dr. Whiteside stated that this see-sawing between wet and dry environments occurred as atmospheric carbon dioxide levels rose from around 1,200 part per million in the oldest rocks sampled up to 2,400 parts per million in the youngest rocks included in the study.  These levels are well in excess of the current CO2 levels in our atmosphere (400 parts per million), but as global warming occurs and the amount of green house gases like carbon dioxide in the atmosphere increases, then we too, are likely to experience much more extremes in world weather.

Ian Glasspool, a specialist in studying ancient plant remains, examined the layers of charcoal that could be found in those sediments associated with the drier, hotter climate.  These are the remains of trees that were caught up in forest fires that periodically swept through this part of the world in the Late Triassic.  He measured the reflectiveness of the charcoal to estimate the intensity of the wildfires that had occurred.  The suggestion is that, the greater the amount of fuel available for a fire to consume, then the greater the heat generated.  The biomass available to burn would be directly related to dry conditions, the drier the climate the greater likelihood of very hot forest fires due to the presence of so much combustible material.

The evidence from the charcoal samples support the idea of a tropical climate swinging violently from extremes.  Severe droughts and forest fires would have continually reshaped the vegetation available for plant-eating dinosaurs.  Perhaps the large bodied, Sauropodomorphs, with their much greater food demands compared to other plant-eating reptiles, were not able to cope with the changes in the flora.

 The Field Team Excavating Vertebrate Fossils

A field team excavating vertebrate fossil remains (Ghost Ranch).

A field team excavating vertebrate fossil remains (Ghost Ranch).

Picture Credit: Randall Irmis

Note the clearly defined bands of different rocks which is a hall mark of the Chinle Formation.  The layers represent different deposition environments, the red sandstones are coloured due to the amount of iron minerals that they contain.  In the published academic paper that outlines this research, the scientists conclude that extreme climate fluctuation led to ecosystem instability in the tropics, which in turn suppressed the rise of the large, plant-eating dinosaurs in these regions.

Warm-Blooded versus Cold-Blooded

This new study may go some way to explain why fossils of small Theropod dinosaurs are found amongst the vertebrate fossil assemblage, but the remains of large Sauropodomorphs are extremely rare.  Although this new research provides a fascinating insight into an prehistoric ecosystem, it throws up some intriguing but controversial ideas.  The scientists postulate that these extreme climates prevented large, active, warm-blooded herbivorous dinosaurs from becoming established in sub-tropical low latitudes until much later in the Mesozoic.  It is suggested that the higher metabolic rates of plant-eating dinosaurs which were endothermic or had a form of endothermy (warm-bloodedness), prevented them from getting a foothold.  They would have needed greater amounts of food to sustain them when compared to the other types of, presumably, cold-blooded reptile that did live in those regions.  The debate over dinosaur metabolism is not resolved and even if the majority of the Dinosauria were endothermic or even mesothermic (a combination of cold-blooded and warm-blooded features), the early long-necked dinosaurs and their descendants, the Sauropoda, may have been entirely ectothermic.

The Femur of a Small Meat-Eating Theropod Dinosaur Excavated by the Researchers

A fossilised dinosaur thigh bone (Ghost Ranch), only small dinosaurs were present close to the Equator.

A fossilised dinosaur thigh bone (Ghost Ranch), only small dinosaurs were present close to the Equator.

Picture Credit: Randall Irmis

The small scribe provides a simple scale.  The distal end of the femur is towards the left of the photograph.

To read a short article about another early meat-eating dinosaur from the Ghost Ranch site: Buck Toothed Vicious Dinosaur Daemonosaurus chauliodus

What is Oolitic Limestone?

Oolite (Egg Stone) Get up Close to Limestone

One of the joys of having Smartphones around the office is that these can be borrowed and taken out on fossil hunting expeditions.  Yes, they have all sorts of features, most of which we don’t use, but the camera has proved a boon. With twenty megapixels to play with team members have been able to take some lovely photographs of fossil discoveries and geological landscapes.  With this sort of imaging technology widely available there are more pictures of fossils being taken than ever before, but sometimes the rocks that contain the fossils can prove to be just as interesting, take oolitic limestone for example.

 A Photograph of Oolitic Limestone (Building Stone)

"egg stone" seen in a building.

“egg stone” seen in a building.

Picture Credit: Everything Dinosaur

The picture above shows Cotswold building stone (Middle Jurassic), limestone that was laid down in a marine environment and a number of small shelly fossils have been preserved along with natural casts of shells.  If you were to run your hand over this finely chiselled piece of building stone it would still feel quite rough, having the texture of coarse sand paper.  It is oolitic limestone, otherwise known as “egg stone” and close up the surface of the stone has a remarkable appearance.

A Close Up of the Limestone Material

Made up of tiny spherical shapes.

Made up of tiny spherical shapes.

Picture Credit: Everything Dinosaur

The powerful digital camera on the Smartphone can pick up fine details such as the small, bubble-like appearance of the surface of the limestone.  These are the remnants of the ooliths (sometimes also called ooids) that make up the rock.  Grains of sand or fragments of seashell are rolled around the sea floor and as they do, they collect calcium carbonate (CaCO3).  Concentric layers are formed and these give the rock its characteristic “egg stone” appearance, as the surface of the rock looks like fish roe (fish eggs). Hence the term oolitic limestone.

Oolite (egg stone) is sedimentary rock and although most ooids are formed from the collection of calcium carbonate, this is not always the case as these structures can be composed of phosphate, dolomite or even chert.  The ancient Greek word for egg is  òoion and this might be the source of the derivations associated with this geologic structure.  In geology, sedimentary rock can be classified according to the composition of the rock as well as the diameter of the “egg stone” structures that are observed within it.  For example, oolites are technically defined as being composed of ooids that range in diameter between 0.25 mm to 2 mm.  Rocks composed of ooids of a larger than 2 mm diameter are called pisolites (made up of spherical shapes called pisoids).  The terms pisolite and pisoids come from the ancient Greek word for pea, so think of the size of the spherical shapes observed in the stone like a group of small peas.

Oolitic Limestone can be Full of Fossils

Fossil shell fragments in the oolitic limestone.

Fossil shell fragments in the oolitic limestone.

Picture Credit: Everything Dinosaur

Ooids are normally formed in warm, shallow seas that contain a lot of calcium and other minerals dissolved within the seawater.  Intertidal movements or currents aid in the transport of the material which helps in the formation of the ooid structures, but oolitic material can also form in freshwater.  Fragments of shell or a sand grain can act as a “seed” giving the calcium carbonate a medium which it can form around.  As these tiny “seeds” tumble around the sea bed they accumulate layers of precipitated calcite (another term for calcium carbonate), the size of the ooid (or pisoid) formed indicates the length of time the object has been exposed to the sea water before being buried by further sediment deposition.  Therefore, pisoids, being larger than ooids have been present on the sea floor longer than ooids.  Oolites with their “egg stone” grains superficially resemble sandstone and they can be white, grey or even yellow in colour (such as Portland limestone).  Under a high powered magnifying glass (or within a 20 megapixel image), the concentric rings which form the ooids can be easily made out.

Oolitic limestones are popular building materials, for example Cotswold limestone (oolitic limestone), as they are hard, resist erosion and come in a variety of hues and colours.  As they have an even structure they can be cut or sculpted in any direction.  Take a look at some of the older, stone buildings in your town.  If you live in the UK, chances are that some of these building stones are oolitic limestone and if you have a powerful camera you can record surface details yourself and record the ooids.

Washington State 37th U.S. State with a Dinosaur?

 Which States in the USA Don’t Have Dinosaur Fossils?

Everything Dinosaur’s recent article on the describing of a dinosaur fossil bone found on Sucia Island (Washington State) set team members thinking.  The fossil, which is believed to represent the partial left femur of a tyrannosaurid was the first dinosaur bone to be scientifically described from Washington State.  A number of media sites and scientific publications that covered this story listed Washington State as the latest and thirty-seventh U.S. State to have had dinosaur fossils discovered within its boundaries.  Of the fifty States that make up the USA, more than two-thirds of them are associated with the Dinosauria, either body or trace fossils or both.

The Partial Left Femur Identified as Tyrannosaur Fossil

Details of the partial left femur.

Details of the partial left femur.

Picture Credit: PLOS One with additional annotation by Everything Dinosaur

To read Everything Dinosaur’s article on the fossil discovery: The First Dinosaur Fossil Described from Washington State

So what about the remaining thirteen States in America, those inferred not to have dinosaur fossils?  Is this a case of there being none found as yet or does the fossil discovery in Washington State represent, in all likelihood, the last State in the United States to be added to the “dinosaur club”?

Let’s look at this in a little more detail.

Which States Don’t Contain Dinosaur Fossils?

Identifying the thirteen States* that don’t contain dinosaur fossils is quite a tough ask for a company this side of the Atlantic.  However, team members at Everything Dinosaur have been putting their heads together and have come up with the following list (which may or may not be accurate).

    1. Hawaii – the Hawaiian archipelago was the fiftieth and most recent State to join the USA.  As it is almost entirely made up of volcanic rock (igneous) and since it is a relatively recent geological feature, probably less than six million years old, we can state with confidence that no dinosaur fossil material will be found in the island’s rock formations.  That’s the easiest one out of the way.
    2. Florida – the “Sunshine State” it might attract millions of tourists but there are very probably no dinosaur fossils to be found.  The landmass we know as Florida today did not form in the Mesozoic.
    3. Louisiana – in the north-western portion of the State, there are some small outcrops of marine shales that were deposited in the Late Cretaceous.  As far as we know, no dinosaur fossils have been associated with this strata (located around Bienville Parish).  It is extremely unlikely that dinosaur fossils could be found in Louisiana, but it could happen.
    4. Mississippi** – the Mississippi river and delta deposits are far to recent to provide the opportunity to find dinosaur fossils.  However, in the far north-east of the State there are small exposed areas of Upper Cretaceous aged marine deposits, predominately chalk.  As far as we know no dinosaur fossils have been found and it is extremely unlikely, however, if you were to go and look, try around Ponotoc and Union Counties – we wish you luck.  South-east USA sorted (we think).
    5. West Virginia – moving up the eastern seaboard of the United States, the next candidate is West Virginia.  As far as we know at Everything Dinosaur, there are no sedimentary rocks dating from the Mesozoic to be found in this State, erosion and other forces have removed them, therefore no dinosaur fossils.
    6. Rhode Island – the smallest State in the USA.  Triassic and Jurassic sedimentary deposits are absent (we think), very few Cretaceous outcrops present, so no dinosaur fossils.
    7. New Hampshire – erosion of sedimentary materials and intrusions of igneous and metamorphic rocks leaves virtually no Mesozoic aged sedimentary formations in the State.  We don’t think any dinosaur fossils have been found here.
    8. Vermont – Triassic and Jurassic aged sediments eroded away and very little Cretaceous aged deposits exposed.   All of these Cretaceous deposits not fossiliferous, so no dinosaur fossils as far as we know discovered in Vermont.
    9. Maine – in the far north-east of the United States there is a huge gap in the geological record with most Late Palaeozoic, Mesozoic and Cenozoic fossils eroded away (blame the glaciers and so forth).  As a result, once again, as far as we know dinosaur fossils recorded from the State of Maine = zero.  So that’s the eastern seaboard and the far north-east taken care off.
    10. Michigan – still in the Eastern Time Zone, but no dinosaur fossils have been found on either peninsula that make up this State.  Lots of invertebrates et al, but no dinosaurs (we think).
    11. Ohio – thanks to glaciation and other forms or erosion, Mesozoic aged sedimentary rocks are virtually absent.  Dinosaurs did probably roam in this part of the world but their fossils have long since be eroded away.
    12. Indiana – just like its eastern neighbour Ohio, blame the glaciers for the loss of the Mesozoic strata.  So no dinosaur fossils in Indiana either, but just like in Ohio, they did probably live in this neck of the woods.
    13. Kentucky – south of Indiana to the “Bluegrass State”.  As far as we can work out from our own notes, there are few Mesozoic rocks exposed (eroded away no doubt).  Some Cretaceous aged outcrops are present and we have some tentative notes of plant fossils from the Cretaceous, but alas, no evidence of the Dinosauria.  Hold on a minute, that should be it, but we still have some more States to go.
    14. Illinois – into the Central Time Zone but just like its eastern neighbour Indiana, erosion has led to the removal of much of the Mesozoic strata.  Some Cretaceous-aged deposits can be found in the south of this State, but as far as we know, although dinosaurs may have lived in this part of the world there is no fossil evidence for them.
    15. Wisconsin – substantial erosion has removed the dinosaur fossil bearing strata, so according to our notes and database, there are no dinosaur fossils associated with the State of Wisconsin.

States in America with Dinosaur Fossils (2015)

Dinosaur Fossils by U.S.State.

Dinosaur Fossils by U.S. State.

Picture Credit: Wikipedia Commons (map) Everything Dinosaur (annotations)

According to our research, the figure of thirteen U.S. States not having dinosaur fossils associated with them is inaccurate. Of course, our own database could be wrong but we make it fifteen States without any evidence of the Dinosauria.  Thanks to mountain building, glaciation, the construction of huge urban developments and the fact that parts of the United States simply did not exist during the time of the dinosaurs, these are the States that lack any dinosaur fossils.

We admit, we could have got this wrong and we would welcome any comments to help provide a more accurate picture.

Additional Notes

Thanks to J. Slattery for helping with this, we have received information about Late Cretaceous dinosaur fossils from Mississippi**.  It seems that in some uncovered outcrops of Upper Cretaceous age which represents shallow marine deposits, fragmentary dinosaur fossils (teeth and bones) have been found as a result of what we tend to call “bloat and float”.  A dinosaur carcase being washed out to sea and then being scavenged before sinking and settlement.

Fossil Site Threatened (Hall Dale Quarry)

Former Quarry Could be Transformed into Housing and Commercial Development

The huge Hall Dale Quarry near Matlock, Derbyshire, could be transformed, with the potential loss of an amazing fossil location, if the local authority grants permission for a mixed residential and commercial development on the site.  Hall Dale Quarry is a disused limestone quarry.  We at Everything Dinosaur, don’t know when the quarrying of limestone blocks ceased, what we do know is that the rocks exposed at this location contain a huge diversity of Carboniferous invertebrate fossils.  Fossils are extremely common at the quarry, whilst many amateur collectors split the boulders with heavy-duty chisels to access the fossil material, just a few minutes exploring the scree on the quarry floor will yield plenty of specimens.  Fossils of a variety of Brachiopods, Crinoid stems and large Corals litter the site and with careful searching some nice examples of marine Gastropods (mainly internal moulds), can be discovered too.

The strata represents a shallow, marine environment and the rocks at the quarry are part of the Eyam limestone formation.  They date from the Early Carboniferous (Visean faunal stage of the Middle Mississippian Epoch [345-328 mya]).  The site is hidden from the road and is approached via a small path leading through a wooded area, although it is just a few minutes’ drive from the bustling centre of the Derbyshire market town of Matlock, once at the quarry face, it’s a different world.  On the day Everything Dinosaur visited, the quarry was deserted, we did not see a single person for the best part of three hours.

A View from the Helicopter Pad at Hall Dale Quarry

Hall Dale Quarry (Derbyshire)

Hall Dale Quarry (Derbyshire)

Picture Credit: Everything Dinosaur

The rock strata forms a series of platforms (three in total), Hall Dale Quarry is a popular location with climbing clubs, the sheer rock faces and huge piles of stone provide plenty of different climbing routes to explore.  We would advise that fossil collectors stay on the ground level, there are plenty of fossils to be found and there is no need to climb the boulders.

Enormous Boulders at Hall Dale Quarry

Huge boulders - can you see our rucksack?

Huge boulders – can you see our rucksack?

Picture Credit: Everything Dinosaur

During our research, prior to our fossil hunting trip, we visited the excellent website of UK Fossils: UK Fossils.  As we prepared for our visit, we came across a news article from November 2014 that outlined plans for the development of this rural space, what is termed a brownfield site.  4M Property Partners had submitted plans to convert the quarry into a development consisting of mixed residential and commercial properties.  Plans had been submitted to the council to build some 220 houses, and to convert 400 square metres into a restaurant and a café.  In addition, the planning proposal contained details of some 6400 square metres of office space.  We at Everything Dinosaur are not sure exactly how fossil collecting would be affected by these developments, we are also unsure as to how the planning application has progressed.  However, we would like to express our concern that such an amazing place might be lost forever.

Whilst we can appreciate that Matlock, like many towns in the UK, may have a need for more houses and that such a development might boost the local economy, as we stood in the quarry, totally in awe of the spectacular scenery and surrounded by evidence of a tropical, marine environment that existed some 340 million years ago, it seemed such a shame that this location might soon be unrecognisable.

Many Different Types of Invertebrate Fossil can Be Found in the Scree

Fossils can be found in the scree.

Fossils can be found in the scree.

Picture Credit: Everything Dinosaur

There may be an urgent need for more local housing.  The town of Matlock might desperately require additional commercial properties.  We feel that we are unable to comment with regards to these development plans, but we sincerely hope that the developers have at least considered the need to preserve some part of this remarkable location’s fossil heritage.  There are fewer and fewer places in this country, where people can simply stop and stare and admire rock formations and the fossil treasures they contain within.  These special sites demonstrate the rich geology of our landscape and allow visitors to explore life in the past.  We hope that any development is undertaken in sympathy with the astonishing geology of this location.

A Few Minutes Collecting and So Many Fossils

A multitude of fossils can be picked out from the scree.

A multitude of fossils can be picked out from the scree.

Picture Credit: Everything Dinosaur

Wishing to express our concerns, the team member who visited the site contacted the planning department of Derbyshire Dales District Council.  A very helpful person in the department explained that the planning team could be emailed, allowing concerns about the need to develop the location in sympathy with the geology of the area to be put on record.  Everything Dinosaur subsequently did this and in addition, emailed Natural England to raise awareness of the development of this brownfield site with that organisation.

Raising Awareness About the Potential Loss of the Quarry

If you have collected fossils at Hall Dale Quarry and wish to make a point with reference to the re-development of this site and the potential loss of this fossil collecting location, then we would urge you to do so.

Planning application reference: 14/00541/OUT (please quote this reference when emailing the planning department or Natural England).

Email: to contact Derbyshire Dales District Council (we would advise that you include a contact telephone number in your email, so that a planning team member can get in touch)

Email: (again quoting planning reference: 14/00541/OUT) to get in contact with Natural England

Whilst we do understand the difficult and often challenging job of district councils and we aware of the potential economic benefits to the local community this project may bring.  We at Everything Dinosaur feel that it is important, to at least place on record a desire to consider the development of Hall Dale Quarry which takes into account the remarkable fossil bearing strata to be found at this location.

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