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Articles, features and stories with an emphasis on geology.

9 12, 2018

“A Guide to Fossil Collecting on the West Dorset Coast”

By | December 9th, 2018|Book Reviews, Dinosaur Fans, Geology, Main Page, Photos/Pictures of Fossils, Press Releases|0 Comments

“A Guide to Fossil Collecting on the West Dorset Coast” – Book Review

At a conference in a rather chilly Helsinki held seventeen years ago this week, delegates of the World Heritage Committee of the United Nations Educational, Scientific and Cultural Organisation (UNESCO), confirmed that World Heritage Site status would be conferred upon a 95-mile stretch of the coastline of southern England covering the east Devon and Dorset coast.

In the minutes of the conference, the reason for this award was recorded:

“The Dorset and East Devon Coast provides an almost continuous sequence of Triassic, Jurassic and Cretaceous rock formations spanning the Mesozoic Era, documenting approximately 185 million years of Earth history.  It also includes a range of internationally important fossil localities – vertebrate and invertebrate, marine and terrestrial – which have produced well-preserved and diverse evidence of life during Mesozoic times.”

However, this description does not convey the true majesty of this location, nor does it provide a sense of awe that this part of the British Isles inspires in so many people.  Neither does it do justice to the simple pleasure of finding a fossil, gazing at it and realising that you are the first living creature in 180 million years to set eyes upon the petrified remains of what was once another inhabitant of our planet.

Then a book is published, a book that provides a sense of the stunning natural landscape, a book that transports the reader back in time, a book that conveys the sense of excitement and achievement associated with fossil collecting – “A Guide to Fossil Collecting on the West Dorset Coast” – does all this and more.

The Front Cover of “A Guide To Fossil Collecting on the West Dorset Coast”

"A Guide to Fossil Collecting on the West Dorset Coast" published by Siri Scientific Press

A beautifully illustrated guide to fossil hunting on the West Dorset coast.  RRP of £18.95 – highly recommended.

Picture Credit: Siri Scientific Press

Conveying a Sense of Beauty, Conveying a Sense of Wonder

Authors Craig Chivers and Steve Snowball focus on one part of the “Jurassic Coast”, that beautiful coastline that runs east from Lyme Regis to the foreboding cliffs of Burton Bradstock.  First the scene is set.  There is a brief description of the geological setting and an outline of the contribution to science of arguably Dorset’s most famous former resident, Mary Anning, and then the reader is taken in Mary’s footsteps through a series of guided walks travelling eastwards along the coast and forwards in time to explore the geology and remarkable fossil heritage of this unique sequence of sedimentary strata.

The Book is Filled with Stunning Photographs of Fossil Discoveries

Prepared specimen of Becheiceras gallicum.

A Lower Jurassic ammonite (Becheiceras gallicum) from the Green Ammonite Member (Seatown, Dorset).

Picture Credit: Siri Scientific Press (fossil found and prepared by Lizzie Hingley)

A Reference for All Collectors and Fossil Enthusiasts

Drawing on their detailed knowledge of fossil collecting, Craig and Steve describe what to look for and where to find an array of fossil specimens along this part of the “Jurassic Coast”.  The landscape is vividly portrayed and the book provides a handy, rucksack-sized reference for fossil collectors, whether seasoned professionals or first time visitors to Dorset.  We commend the authors for including copious amounts of helpful information on responsible fossil collecting and for publishing in full the West Dorset Fossil Collecting Code.

Breath-taking Views of the Natural Beauty of the Coastline

Fossil hunting around Seatown.

Golden Cap – excursions around Seatown.  Majestic views of the “Jurassic Coast”.

Picture Credit: Siri Scientific Press

Recreating Ancient Environments

Talented palaeoartist Andreas Kurpisz provides readers with digital reconstructions of ancient environments and brings to life the fossil specimens, showing them as living creatures interacting with other prehistoric animals in a series of Jurassic landscapes and seascapes.  These reconstructions help to document the changing environments that are now preserved within the imposing cliffs of this remarkable part of the British coastline.

Crinoids (Sea Lilies) from the West Dorset Coast

Crinoids from the "Jurassic Coast".

The book contains stunning photographs of fossils from the “Jurassic Coast”.

Picture Credit: Siri Scientific Press

Spokesperson for Everything Dinosaur, Mike Walley commented:

“This guide manages to capture the beauty and the fascination of this part of the “Jurassic Coast”.  It is a “must have” for all fossil collectors and if ever the delegates at that UNESCO conference needed to reaffirm their decision to grant this stunning part of the British coastline World Heritage Site status, this book provides ample evidence to justify their original decision.”

For further information and to order this exquisite guide book: Order “A Guide to Fossil Collecting on the West Dorset Coast”

15 09, 2018

A View of the Jurassic Coast

By | September 15th, 2018|Geology, Main Page, Photos|0 Comments

Viewing the “Jurassic Coastline”

The famous “Jurassic Coast” stretches for 95 miles (155 kilometres).  It runs from Exmouth in East Devon to Studland Bay in Dorset and the layers of sedimentary rock record approximately 185 million years of Earth’s history. This coastline on the English Channel was designated at England’s first UNESCO natural World Heritage Site back in 2001 and although it attracts hundreds of thousands of tourists every month during the summer, there are still quiet parts to be explored and enjoyed.

A View of the Jurassic Coast Towards Burton Bradstock East of Lyme Regis

Heading east from Lyme Regis to Burton Bradstock.

The view towards West Bay and Burton Bradstock.  A beautiful day on the UNESCO World Heritage site, the “Jurassic Coast”.

Picture Credit: Everything Dinosaur

The photograph shows a section of the sandstone cliffs that lie to the east of Seatown in Dorset, the view shows West Bay and on the far right the sheer sandstone cliffs of Burton Bradstock can just be made out.

What a terrific view, this area of southern England may attract huge numbers of visitors every year, but there are still some areas, especially those more difficult to access parts of the coastline, that can provide opportunities to have a small section of a UNESCO World Heritage site, all to yourself, for a few minutes at least.

18 07, 2018

The Dinosaur Park and Hell Creek Formations

By | July 18th, 2018|Adobe CS5, Dinosaur Fans, Everything Dinosaur News and Updates, Geology, Main Page|0 Comments

The Dinosaur Park Formation (DPF) and the Hell Creek Formation (HCF)

We have been asked to give a brief explanation of the different dinosaurs associated with two famous North America rock formations.  A comment on the different dinosaur faunas associated with the Dinosaur Park Formation (DPF) of southern Alberta and the Hell Creek Formation (HCF), which is mostly associated with the state of Montana but also outcrops in North and South Dakota as well as Wyoming.

The Badlands of the Dinosaur Park Formation (DPF) – Hunting for Dinosaur Fossils

Looking for Late Cretaceous dinosaur fossils.

A typical view of the “Badlands” of the Dinosaur Park Formation.  The red arrow in the picture highlights the layer in which the fossils of a new type of horned dinosaur were discovered.

Picture Credit: Everything Dinosaur

The Badlands

Both the Hell Creek Formation and the Dinosaur Park Formation are referred to as “Badlands”, this term is derived from the French phrase “les mauvaises terres” and dates back to the early years of exploration of these vast tracts of land.  The term describes an area largely devoid of vegetation that is subjected to rapid erosion caused by wind, rain and running water.  The DPF is older, the strata were laid down between 76.5 and 75 million years ago in the Late Cretaceous (Campanian faunal stage).  In contrast, the Hell Creek Formation is younger.  The rocks were formed at the very end of the Cretaceous (Maastrichtian faunal stage) and the strata records the transition from the end of the Cretaceous into the Palaeocene, the first Epoch of the Cenozoic.  The HCF spans approximately 66.8 to 66 million years ago and documents evidence of an extra-terrestrial impact event preserved as a thin clay layer that contains large quantities of the rare Earth element iridium, marking the Cretaceous-Palaeogene boundary, representing an extinction event denoting the end of the age of the dinosaurs and the start of the Cenozoic.

Looking for Fossils – Hell Creek Formation

Looking for fossils - Hell Creek Formation.

Prospecting for fossils – Hell Creek Formation (Montana).

Picture Credit: University of California Museum of Palaeontology

The Ancient Environments

The strata that forms the DPF represents a coastal plan environment, crossed by numerous large rivers.  The majority of the rocks are sandstones and mudstones, although there are layers of volcanic ash (bentonite), which resulted from the sporadic eruptions of volcanoes in the region. In the upper part of the DPF, coal deposits can be found (Lethbridge coal zone), representing deposition in a swampy environment.  The sea gradually encroached onto this coastal plain and the area was eventually flooded, resulting in the deposition of the marine shales that represent the Bearpaw Formation that overlies the DPF.

The Hell Creek Formation was created under similar circumstances.  It too represents clays, mudstones and sandstones deposited on a delta, a low-lying flood plain crossed by many rivers.  The HCF also has peaty, coal-like deposits (lignite), representing deposition in coastal swampy environments.

The Palaeoenvironment of the Dinosaur Park Formation

The fauna and flora of Alberta 75 million years ago

Alberta around 75 million years ago (Dinosaur Park Formation).

Picture Credit: Julius Csotonyi

A Chasmosaurus and a Lambeosaurus feeding during the late evening, a typical scene representing the biota associated with the DPF.

The Palaeoenvironment of the Hell Creek Formation

Triceratops dinosaur illustration.

Triceratops was one of the last dinosaurs to evolve.  A resident of the Hell Creek Formation.

Picture Credit: Julius Csotonyi

A Triceratops grazes next to a palm tree on the coastal plain that is represented by deposits that help to make up the Hell Creek Formation of Montana.

Different Time Periods – Different Dinosaurs

Both the HCF and the DPF are famous for extensive dinosaur fossils.  It is worth remembering that numerous other kinds of animal (and plants) are represented in the fossil record of these two formations.  Although, the dinosaur fauna is similar between the DPF and the HCF, for example the terrestrial large herbivores are dominated by duck-billed dinosaurs and Ceratopsians, the genera represented are very different.

In simple terms, the stage scenery might be similar and the cast of characters reminiscent but the actors on the stage are different.

Typical Dinosaurs from the Dinosaur Park Formation (Campanian Faunal Stage of the Cretaceous)

Dinosaur Park Formation dinosaurs.

Typical dinosaur fauna of the Dinosaur Park Formation (Alberta, Canada).

Picture Credit: Everything Dinosaur

Typical Dinosaurs from the Hell Creek Formation (Maastrichtian Faunal Stage of the Cretaceous)

Dinosaurs of the Hell Creek Formation.

Typical dinosaurs of the Hell Creek Formation.

Picture Credit: Everything Dinosaur

We are looking forward to our visit to the Beacon Museum at Whitehaven (Cumbria).  Everything Dinosaur will be taking visitors on a fossil hunt and we hope to be able to give away real dinosaur bones.

15 07, 2018

Carboniferous Fossils on a Welsh Hillside

By | July 15th, 2018|Geology, Main Page, Photos/Pictures of Fossils|0 Comments

Mynydd Marian Nature Reserve and Fossils

Overlooking the Welsh coast between Llandudno and Rhyl is the beautiful but quite compact nature reserve of Mynydd Marian.  It forms part of a range of low limestone hills that can be found along this part of the coast of North Wales.  The location, a SSSI (Site of Special Scientific Interest), is popular with walkers keen to spot the myriad of different insects and the orchids that thrive on the limestone soils.  The exposed cliffs that were once quarried for their limestone, attract local climbing groups.  However, there is plenty to see for fossil hunters too.  The strata were laid down over 320 million years ago (Carboniferous), it was formed from the compressed shells of countless marine invertebrates that thrived in a warm, shallow sea.  If the numerous stone walls are examined carefully, then lots of fossils of brachiopods and the button-like segments of marine crinoids can be spotted.

A Crinoid Segment Spotted in a Dry-stone Wall (Mynydd Marian)

Spotting a piece of a Carboniferous crinoid.

A crinoid stem exposed in a stone wall at Mynydd Marian nature reserve.

Picture Credit: Everything Dinosaur

There is little scree to be found and we would not advise climbing the steep faces of the quarry but if the rocks that comprise the stone walls are examined, then many fossils can be seen.

Spotting Fossils at Mynydd Marian Nature Reserve

Spotting fossils at Mynydd Marian

A crinoid segment (red arrow) and a mould revealing the impression of a brachiopod shell (green arrow) on the surrounding rock.

Picture Credit: Everything Dinosaur

The picture (above), shows two fossils preserved in the rocks of a dry-stone wall.  The red arrow is pointing to a crinoid segment, whilst the green arrow indicates a mould left in the surrounding matrix by a brachiopod shell.  There is no need to disturb the rocks in the wall, careful observation is all that is required and you will soon start to discern the different types of fossil.

An Impression of the Shell of a Brachiopod preserved in the Limestone

A view of a lost world, an impression of the shell of a brachiopod preserved in the limestone rock.

A glimpse into a lost world, an impression of the shell of a brachiopod preserved in the limestone.

Picture Credit: Everything Dinosaur

12 07, 2018

In the Pink! Life’s First Colour

By | July 12th, 2018|Geology, Main Page, Palaeontological articles|0 Comments

Scientists Identify the World’s Oldest Biological Colours

A team of international scientists including researchers from the University of Liège, Florida State University and the Australian National University, in collaboration with a colleague based in Japan have discovered the oldest colours preserved in the fossil record.  An analysis of the remains of microscopic, 1.1 billion-year-old cyanobacteria suggest that life back in the Proterozoic was “in the pink”.  Pink coloured pigments have been extracted from ancient marine shales that form part of the Taoudeni Basin of Mauritania (north-western Africa).

When Held Up in the Light the Pink Colouration can be Seen

A vial of pink pigments porphyrins - representing the oldest intact pigments in the world.

The oldest colours found to date.

Picture Credit: Australian National University

One of the authors of the scientific paper, published in the “Proceedings of the National Academy of Sciences of the USA”, Dr Nur Gueneli (Australian National University), explained that the pigments taken from the marine black shales were more than six hundred million years older than previous pigment discoveries.

Dr Gueneli commented:

“The bright pink pigments are the molecular fossils of chlorophyll that were produced by ancient photosynthetic organisms inhabiting an ancient ocean that has long since vanished.”

Samples of the shales laid down during the Stenian, the last geological period of the Mesoproterozoic Era, were ground into fine powder before the ancient molecules of long extinct cyanobacteria could be extracted and analysed.  The fossils reveal a range of colours from a blood red to a deep purple in their concentrated form, but when diluted, it is the colour pink that dominates.

Dr Gueneli, who undertook this research whilst studying for a PhD added:

“The precise analysis of the ancient pigments confirmed that tiny cyanobacteria dominated the base of the food chain in the oceans a billion years ago, which helps to explain why animals did not exist at the time.”

Lack of Things for Higher Organisms to Eat

Complicated animal life was not able to evolve, according to one hypothesis, as it was restrained by the lack of food in the ocean.  In essence, life on Earth could not pick up the evolutionary pace as food webs were constrained by the amount of primary producers in the ecosystem.  Through the team’s discovery of molecular fossils of the photopigment chlorophyll in 1.1-billion-year-old marine sedimentary rocks, they were able to quantify the abundance of different organisms that uses the sun’s energy to produce food (phototrophs).  Nitrogen isotopic values of the fossil pigments revealed that the Pan-African Ocean was dominated by cyanobacteria, while larger planktonic algae were very scarce.  These findings support the hypothesis that small cells at the base of the food chain limited the flow of energy to higher trophic levels, potentially retarding the emergence of large and complex life.

Associate Professor Jochen Brooks, of the Research School of Earth Sciences (Australian National University), one of the authors of the scientific paper, stated that the emergence of more complex life forms was likely to have been restricted by the limited supply of larger food particles, such as algae.

Associate Professor Brooks explained:

“Algae, although still microscopic, are a thousand times larger in volume than cyanobacteria, and are a much richer food source.  The cyanobacterial oceans started to vanish about 650 million years ago, when algae began to rapidly spread to provide the burst of energy needed for the evolution of complex ecosystems, where large animals, including humans, could thrive on Earth.”

5 07, 2018

Scientists Turn to Fossil Plants to Determine Tibetan Plateau Uplift

By | July 5th, 2018|Dinosaur and Prehistoric Animal News Stories, Geology, Main Page|0 Comments

Plant Fossils Pinpoint the Timing of the Uplift of South-eastern Tibet

The immense Tibetan Plateau which borders the Himalayas, is sometimes referred to as the “roof of the world”.   This foreboding landscape rises thousands of metres above sea level, it harbours a unique ecosystem and is the source of some of the most economically significant rivers in the world.  However, when this plateau was formed and the geological mechanisms that led to this part of Asian being uplifted to form this elevated plain, are poorly understood.

Fossilised plants may help determine when the uplift occurred.  This may seem unlikely, when studying tectonic forces, but by looking at living flora, scientists can determine information about the climate and habitat that the plants are living in from their shape, leaf size and structure.  These same pointers can be identified in fossil plants too.

Plant Fossils Helping to Unlock the Geology of South-eastern Asia

Plant fossils from south-eastern Tibet.

Plant fossils associated with different layers in the Markan Basin provide an indication of climate change and geological uplift.

Picture Credit: Chinese Academy of Sciences

Plants Interact with Their Environment

Plants live at the Earth’s surface and have to constantly interact with the atmosphere, their leaves are very good at recording their surroundings, including properties of the atmosphere that are related to altitude.

Researchers from the Chinese Academy of Sciences (CAS), more specifically from the Xishuangbanna Tropical Botanical Garden (XTBG), have been examining plant fossils from the Lawula Formation in the Markan Basin, south-eastern Tibet.  They have used plant fossil evidence to assess the date of the uplift of south-east Tibet.  The mountain range building may have been accelerated when the Tibetan Plateau was already around three kilometres above sea level and rising to its present-day height.

Fortunately, the strata with plant fossils were found between volcanic ash layers that allowed them to be precisely dated using argon isotope degradation analysis.  It turned out that the fossil assemblages were much older than their relatively modern appearance would suggest.  Several thousand fossil leaves were examined from four different layers of sediment.  Two fossiliferous layers proved to be the most important for this study.  The lower level (MK3), was dated using the isotope analysis to around 34.6 million years ago, whilst the upper layer (MK1), was dated to 33.4 million years ago.  As such, these deposits span the Eocene-Oligocene Epoch Transition (around 33.9 million years ago), a time when there was dramatic climate change.

One of the Fossil Sites (Kajun Village, Markan Basin)

The Markan Basin (south-eastern Tibet).

A view of one of the fossil sites (Kajun Village) currently at around 3,900 metres above sea level.

Picture Credit: Science China Press

Intriguingly, the older layer MK3 is dominated by leaves of the ring-cupped oak and members of the birch family, whereas MK1 consists almost exclusively of alpine taxa with small leaves.  The plant fossils suggest that the habitat changed from a relatively temperate evergreen and deciduous broad-leaved plant dominated flora to alpine scrub.

The CAS research team concluded that during the Eocene-Oligocene Transition, south-eastern Tibet was around three kilometres high and actively rising, close to its present-day height.  The team’s results demonstrate that the onset of geological uplift took place earlier, some ten million years earlier than previously suggested.

The results show that the elevation of south-eastern Tibet took place largely in the Eocene, which has major implications for uplift mechanisms, landscape development and the evolution of the flora and fauna of this region.

The argon isotope analysis of the volcanic ash layers helping to date the Markan Basin fossils, adds to a growing list of Palaeogene sites in this part of Asia, which are actually far older than biostratigraphic and lithostratigraphic data indicate.  The researchers postulate that their study supports the growing body of scientific opinion that the evolution of the highly diverse Asian biota is s Palaeogene, not a Neogene phenomenon and took place before the end of the Eocene.  The evolution of modern-day ecosystems may be deeply-rooted in the Palaeogene and this may have been driven by the changing and complex Tibetan topography and resultant climate change.

The scientists from the Xishuangbanna Tropical Botanical Garden are continuing to collect plant fossils from different parts of Tibet.  They hope to build a model framework which permits a much better understanding of the uplift and the forces involved over deep time.

16 06, 2018

4D Scanning Technology Helps to Predict Lava Flows

By | June 16th, 2018|Geology, Main Page|0 Comments

New Research Helps to Predict Unpredictable Lava Flows

Scientists, including researchers from Manchester University are using the latest 4D technology to predict the behaviour of lava flows after a volcanic eruption.  The results, published in the journal “Scientific Reports” help explain why some lava flows can cover many miles in just a few hours, whilst others travel much more slowly.  Highlighting the hazards posed by fast-moving flows will help to save lives and could lead to better management strategies.

New Technology Helping to Minimise the Threat of Lava Flows following Volcanic Eruptions

Volcanic eruptions in future may not be so deadly.

New technology is helping to predict lava flows.

Picture Credit: Universal Pictures

The research involves studying the processes that take place during crystallisation in basaltic magmas, 4D synchrotron X-ray microtomography technology is being utilised to study lava flow.  It is the first time this kind of 4D scanning technology has been used for investigating crystallisation during volcanic eruptions and for simulating the behaviour of these potentially devastating natural events.

The team, led by Professor Mike Burton, (Chair of Volcanology at Manchester University), monitored crystallisation in magmas, a fundamental process that drives eruptions and controls different kinds of volcanic activity.  Using this new and novel approach the team can, for the first time, watch the crystals grow in three dimensions in real-time, simulating the behaviour of lava flows once a volcano has erupted.  The process is similar to scenes recently witnessed at Kilauea in Hawaii.

The professor explained:

“During volcanic eruptions small crystals grow within magma.  These crystals can greatly change the way magma flows.  Simply put, the more crystals there are the slower the eruption will be which also reduces the speed and distance travelled by lava flows.  The fewer crystals present in the lava means the eruption will speed up, potentially becoming more powerful and devastating.  Our research and this new approach open an entirely new frontier in the study of volcanic processes.”

Studying Samples from Real Volcanic Eruptions

To study the rate of crystal growth, the team set up a sample from a real eruption in a high temperature cell, before performing X-ray CAT scans whilst controlling the temperature of the magma. This allowed the researchers to visualise the formation and growth of crystals, and measure how quickly they grew.

Using this method and technology the researchers can collect hundreds of 3D images during a single experiment. This data is then used in complex, numerical models to fully characterise the behaviour of volcanic eruptions more accurately.

Lead author of the recently published paper, Dr Margherita Polacci (University of Manchester’s School of Earth and Environmental Sciences), added:

“Being able to more accurately predict the behaviour of lava flows could also allow us to help relevant safety agencies devise and develop new safety strategies and actions when dealing with eruptions in populated areas.”

Predicting the Flow of Lava Will Help to Save Lives

Dangerous lava flows.

Dangerous lava flows (Kilauea in Hawaii).

Picture Credit: Reuters

Extending this Technology into Other Fields

The researchers are confident that predicting lava flows will not be the only application for this new technology.  The team expect their research to have implications for mineral extraction as well as other geological processes.  For the time being, any advances in the prediction models for the behaviour of lava flows would be welcomed, given the obvious benefits such tools will have to the authorities when it comes to planning evacuations and minimising the risk to life.

The scientific paper: “Crystallisation in Basaltic Magmas Revealed via in situ 4D synchrotron X-ray Microtomography” by M. Polacci, F. Arzilli, G. La Spina, N. Le Gall, B. Cai, D. Di Genova, N. T. Vo, S. Nonni, R. C. Atwood, E. W. Llewellin, P. D. Lee and M. R. Burton published in the journal Scientific Reports.

Everything Dinosaur acknowledges the help of a press release from the University of Manchester in the compilation of this article.

9 05, 2018

A Weather Forecast from the Cambrian

By | May 9th, 2018|Dinosaur and Prehistoric Animal News Stories, Geology, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

Tiny Fossils Provide Clues to Earth’s Climate 500 Million Years Ago

A joint team of scientists from France and the UK, have plotted the temperature of our planet’s oceans over half a billion years ago using a combination of fossil data and computer-based climate models.  Think of it as a sort of weather forecast from the Cambrian.  This newly published research suggests that the first hard-bodied animals diversified in warms seas, heated by a greenhouse world.  The team’s findings help to expand our knowledge of the environment at the time of the Cambrian explosion, a period in Earth’s history that saw a huge increase in the number and type of marine animal forms.

Life in the Late Cambrian Period

Cambrian life.

Life in the Late Cambrian by Zdeněk Burian.

Picture Credit: Zdeněk Burian

Writing in the academic journal “Science Advances”, the scientists, led by researchers from the University of Leicester, used climate models and the chemical analysis of tiny, shelly fossils preserved in limestone from Shropshire (central England), to calculate the sea temperature during a time of rapid diversity of animal life in the Palaeozoic.  From around 540 to 510 million years ago, the fossil record shows a marked change, as during this period of Earth’s history, virtually all of the animal phyla (including the Chordata – our phylum) appeared.  The idea of a “Cambrian explosion” is a little misleading, the appearance of many new forms of complex animal life may have been gradual, but in terms of the fossil record, sites such as the famous Burgess Shale of British Columbia and Yunnan Province (southern China), have revealed extensive and varied marine ecosystems with large numbers of new types of animal being recorded in the strata.

Analysis of Some of the First Shelly Fossils

Scientists had thought that for much of the Cambrian, our planet was warmer that it is today with no polar ice caps present.  A study of tiny 1 mm long fossils of some of the first animals to produce a hard, shelly exoskeleton has confirmed this hypothesis.  Analysis of isotopes from the tiny shells in combination with the climate models show that at high latitudes (around 65 degrees south), sea temperatures were in excess of 20 degrees Celsius.  This might seem very warm, especially when you consider that this is an evaluation of sea temperatures at approximately 65 degrees south, today, travelling to that latitude would put you on the southernmost fringes of the Southern Ocean and close to Antarctica.  However, the data generated is similar to more recent, better understood, greenhouse climates such as that of the Late Cretaceous.

Reflected Light Microscopy – Brachiopod Fossils Used in the Study

Reflected light microscope images of Cambrian brachiopods.

Reflected light microscope images of some of the brachiopod fossils (phosphatic microfossils), used in this study.

Picture Credit: Leicester University

Co-author of the open access paper, PhD student Thomas Hearing (University of Leicester’s School of Geography, Geology and the Environment), explained:

“Because scientists cannot directly measure sea temperatures from half a billion years ago, they have to use proxy data, these are measurable quantities that respond in a predictable way to changing climate variables like temperature.  In this study, we used oxygen isotope ratios, which is a commonly used palaeothermometer.  We then used acid to extract fossils about 1 mm long from blocks of limestone from Shropshire, UK, dated to between 515 – 510 million years old.  Careful examination of these tiny fossils revealed that some of them have exceptionally well-preserved shell chemistry which has not changed since they grew on the Cambrian sea floor.” 

High Resolution Scanning Electron Microscope (SEM) Images of Brachiopod Fossils Used in the Study

SEM images of brachiopods.

Electron microscope images of some of the brachiopod fossils used in this study. Electron microscopy allows much higher resolution imaging of small structures than normal light microscopy.

Picture Credit: Leicester University

Dr Tom Harvey (University of Leicester) added:

“Many marine animals incorporate chemical traces of seawater into their shells as they grow.  That chemical signature is often lost over geological time, so it’s remarkable that we can identify it in such ancient fossils.” 

Analyses of the oxygen isotopes of these fossils suggested very warm temperatures for high latitude seas (~65 °S), probably between 20 °C to 25 °C.  To see if these were feasible sea temperatures, the researchers carried out climate model simulations for the Cambrian.  The climate model scenarios suggest that the Earth’s climate was in a “typical” greenhouse state, with temperatures similar to more recent and better understood greenhouse intervals known from the Mesozoic and the Cenozoic eras.  Ultimately, this study will help to expand our knowledge of the ecosystem that existed during the Cambrian.

The Highly Fossiliferous Comley Limestones (Shropshire, UK)

A thin section of highly fossiliferous rock of Cambrian age.

A thin section slice through the trilobite-rich Comley Limestones (Shropshire, UK).

Picture Credit: Everything Dinosaur

The curves and white wavy lines in the photograph (above), are preserved exoskeletons of numerous trilobites.

Thomas Hearing concluded:

“We hope that this approach can be used by other researchers to build up a clearer picture of ancient climates where conventional climate proxy data are not available.”

The research was carried out as an international collaboration involving scientists from the University of Leicester (UK), British Geological Survey (BGS; UK), and CEREGE (France).

Everything Dinosaur acknowledges the help of Leicester University in the compilation of this article.

7 04, 2018

Searching for Ancient Settlements at the Bottom of the North Sea

By | April 7th, 2018|Geology, Main Page|0 Comments

International Collaboration to Pinpoint Stone Age Settlements in Doggerland

A two-year marine expedition to pinpoint the location of a prehistoric settlement in the southern North Sea will be officially launched next Tuesday (10th April).  Teams from the University of Bradford, Flanders Marine Institute (VLIZ) and Ghent University will be working together to map and survey an area of the North Sea known as Brown Bank.  This area may have been the site of a substantial Stone Age settlement, prior to the land becoming inundated as sea levels rose at the end of the last Ice Age.

The marine experts hope to undertake an extensive geophysical assessment of the area, before extracting sediment cores that can be examined to establish the palaeo-environment and any evidence of human activity.

The Brown Bank Area of the Southern North Sea

The Brown Bank area of the southern North Sea.

The “Lost Frontiers” project map showing the location of the Brown Bank area in the southern North Sea.

Picture Credit: University of Bradford

The picture above shows the location of the Brown Bank area, approximately sixty miles east of Great Yarmouth.  The circles indicate areas in which archaeological evidence has been discovered in the southern North Sea.

Complimenting the “Lost Frontiers” Project

This two-year research project compliments the Bradford University-led “Lost Frontiers” project, in which archaeologists are mapping the ancient, prehistoric landscape of the North Sea known as Doggerland.  The European Research Council (ERC) is funding the research.  This area, now submerged, once connected the United Kingdom to Europe.  As sea levels rose at the end of the last Ice Age between 8,000 to 10,000 years ago, so the land was gradually lost and all evidence of human settlement and activity was swallowed up by the rising waters.  Scientists working on the Lost Frontiers project have identified river valleys, hills, marshland and what were once great grassy plains stretching across thousands of square kilometres, but despite this, evidence of human activity has remained elusive.

Evidence of Human Activity/Settlement from the Brown Bank Area

Brown Bank Stone Age artefacts.

Brown Bank artefacts – A selection of prehistoric artefacts from Brown Bank collected by Dr Dick Mol including (a ) polished stone axe mace head; b) perforated deer antler socketed adze axe head; c) human mandible, without scale from (Peeters 2011).

Picture Credit: University of Bradford

A Home to Thousands of People

Chance finds by trawlers as they use drag fishing methods in the area have provided tantalising evidence of a hitherto hidden Stone Age world.  Archaeologists have long suspected that this part of the North Sea may have been home to thousands of people, the aim of this new project is to prove that the Brown Bank area, an eighteen-mile-long (thirty kilometres), sand ridge, some sixty miles (one hundred kilometres), east of the Norfolk coast and around fifty miles (eighty kilometres), from Holland, was the location of a prehistoric settlement.

Commenting on the significance of this new research, Professor Vincent Gaffney (Bradford University), stated:

“If it is possible to undertake fieldwork that can locate prehistoric settlement on the Brown Bank this would be a major event.  Until now the majority of Doggerland has been terra incognita in archaeological terms.  If we can begin to locate settlement across the, currently, empty map of the Doggerland, we would open a new chapter in archaeological exploration.”

Professor Vincent Gaffney (University of Bradford)

Professor Vincent Gaffney.

Professor Vincent Gaffney (Bradford University).

Picture Credit: University of Bradford

Ancient River Systems

The team hope to build on previous research carried out by Ghent University in which ancient river systems were plotted running across the southern North Sea area.  Using this data, the researchers have pinpointed one particular area in the Brown Bank where there might have once been a large lake.  If this area was home to a substantial human population, it is likely they would have built a settlement on the lake shore.

A member of the research team, Dr David Garcia Moreno (Ghent University), explained:

“Confirmation of the location of a prehistoric lake near the Brown Bank and the characterisation of the fluvial system associated with it would be a breakthrough.  Such a discovery would have vast implications in our understanding of the palaeogeographic evolution of north-western Europe since the last Ice Age.”

A Map Showing the Approximate Maximum Land Area That Once Joined the UK  and Ireland to the rest of Europe

The extent of the palaeolandscape prior to sea level changes.

Approximate maximum extent of marine palaeolandscapes off the Irish and British coasts.

Picture Credit: University of Bradford

Help from the Belgian Navy

The project’s first phase will involve teams from the UK and Belgium surveying the target area with the assistance of the Belgian research vessel RV Belgica.   This fifty-metre-long vessel will be home to the researchers whilst they build up a detailed map of the physical features of the seafloor.  This survey will help them identify promising areas for further examination in part two of the project.

In the second phase, the team will extract sediment cores from these targets and analyse them to determine the environment of the landscape underlying the Brown Bank and to understand its potential for human settlement prior to its flooding.

Dr Tine Missiaen (VLIZ), stated:

“Submerged landscapes and human settlement in the North Sea did not stop at borders.  International collaboration is indispensable to unravel this unique episode in Europe’s prehistory.  Only the integrated use of novel state-of-the-art techniques will allow us to map and reconstruct these drowned landscapes and settlements with unprecedented detail.”

31 03, 2018

Extinction and Extirpation

By | March 31st, 2018|Dinosaur Fans, Geology, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

Defining Extirpation

The fossil record, despite its extremely fragmentary nature remains the best scientific tool available for learning about life in the past.  It is far from complete and it can only provide a limited amount of information about organisms, ecosystems and palaeoenvironments, but it has provided evidence of extinctions and five major mass extinction events have been identified in the immense time period known as the Phanerozoic.

A Selection of Shark Teeth Fossils

fossilised shark teeth.

A successful fossil hunt, but many organisms are only known from fragmentary fossil material.

Picture Credit: Everything Dinosaur

An Extinction is Forever

Notwithstanding the technological developments heralded by advances in genetics, an extinction is finite.  Extinctions represent the complete, world-wide end of the line for a species.  There are no individuals representing that species to be found anywhere.  Non-avian representatives of the Dinosauria, the long-necked Sauropods for example, are extinct, the very last of these animals, collectively termed Titanosaurs, died out at the end of the Cretaceous, some 66 million years ago.

However, it is important to distinguish local extinctions, whereby an organism becomes extinct in a region or area, from true, global extinction.  A species or genus may die out in one part of the area where it is distributed, but it might be thriving, or at least surviving everywhere else.  Identifying local extinctions, especially in an incomplete fossil record, where many of the fossils have been transported long distances and with a record of moving continents (tectonic plate theory), is extremely challenging.

Extirpation

The correct scientific term for a local or regional extinction is “extirpation”, an organism may cease to exist in one area but could still be found in other areas.  Palaeontologists usually use the term extinction in its correct sense, noting the complete disappearance of an organism.  Thanks to the vagaries of the fossil record, identifying extirpation events in deep time is extremely difficult.  The Liaoning Province of northern China has provided scientists with numerous examples of feathered dinosaurs.  Their remains are often beautifully preserved, a result of the way in which these animals may have died .  Corpses were deposited in lakes and sank to the muddy, still bottom before being rapidly buried by fine ash deposited over the region by the nearby volcanoes.  Whether some of these animals drowned, or whether their deaths were directly attributable to the volcanism is difficult to say for certain in most cases.

Zhenyuanlong Fossil (Zhenyuanlong suni) from Liaoning Province

Zhenyuanlong fossil.

Large-bodied, short-armed Liaoning dromaeosaurid described in 2015 (Zhenyuanlong suni).

Picture Credit: Chinese Academy of Geological Science

Unfortunately, whilst a devastating deposit of volcanic ash, perhaps a pyroclastic cloud or the release of toxic carbon monoxide fumes could have led to the deaths of many animals within a habitat, it is very difficult to determine whether such events led to a local extinction (extirpation).  In the case of the Liaoning fossils, the stratigraphic record would indicate numerous volcanic episodes but whether a single episode or a series of catastrophic events led to the demise of an entire taxon in the region it is impossible to say.  However, the forest ecosystem with its large lakes would have suffered a loss of individuals and probably a reduction in diversity over time.

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