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Articles, features and stories with an emphasis on geology.

3 08, 2020

Scotland’s Own “Jurassic Park”

By | August 3rd, 2020|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Geology, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

Jurassic Fossils from the Isle of Skye Globally Significant

The filming might have resumed for the next instalment in the “Jurassic Park/World” franchise last week, but in the scientific community there has been an important development in the study and protection of Scotland’s very own “Jurassic Park”.

Scientists from the University of Oxford, University College London, Birmingham University the University of Edinburgh and the National Museum of Scotland have published a new scientific paper that emphasises the importance of vertebrate fossils from the Isle of Skye.

The Isle of Skye is Heralded as One of the Most Important Places in the World for Middle Jurassic Vertebrate Fossils

Isle of Skye Sauropods.

The Isle of Skye (Bathonian faunal stage).  A newly published scientific paper heralds the vertebrate fossils from the Kilmaluag Formation on the Isle of Skye as “globally significant”.

Picture Credit: Jon Hoad

The Kilmaluag Formation

Outcrops of the Bathonian-aged Kilmaluag Formation on the Trotternish peninsula on the Isle of Skye hold vital information on how vertebrate life was evolving and changing around 167 million years ago.  The strata contain both body and trace fossils of numerous tetrapods including dinosaurs.  Since there are not that many highly fossiliferous sites around the world providing evidence of terrestrial ecosystems and biota from back in the Middle Jurassic, the Isle of Skye has long been recognised as a hugely significant.

The area was given greater legal protection last year, when the Scottish Government signed a Nature Conservation Order (NCO), to assist in the protection of the rare vertebrate fossils found in the area and to deter irresponsible fossil collecting on the island.

To read about the provision of the Nature Conservation Order: Legal Protection for Isle of Skye Fossil Sites.

In this new study, the researchers which include Scottish palaeontologist Elsa Panciroli, a research assistant in the department of Evolution and Palaeobiology at the University of Oxford, conclude that unlike other contemporaneous fossil localities from England, the strata of the Kilmaluag Formation provides partial skeletons, providing unprecedented insights and new data.  The research team state that this location has yielded predominantly small-bodied tetrapods including amphibians, many types of reptiles (including pterosaurs and dinosaurs) and non-mammalian cynodonts as well as early mammals.  An abundant fossil fish and invertebrate assemblage is also reported.

A Sauropod Track from the Isle of Skye

Sauropod track on the foreshore (Isle of Skye).

Sauropod track from the Isle of Skye.  The Trotternish peninsula provides both body and trace fossils, such as this sauropod track for example.

Picture Credit: Jon Hoad

The researchers provide a comprehensive overview of the Kilmaluag Formation, outlining the importance of its geology and the fossil discoveries made to date.  They also present evidence of several species that are being reported from the Isle of Skye for the first time.   The review places the vertebrate faunal assemblage in an international context and confirms the global significance of the region.  Although the dinosaurs grab all the headlines, the Kilmaluag Formation is most likely to provide important information with regards to the evolutionary history of early mammals, the Squamata (lizards and snakes) along with amphibians.

To read Everything Dinosaur’s blog post about damage to dinosaur footprints being reported: Dinosaur Footprints Damaged on the Isle of Skye.

The link between the fossil sites in Wyoming and the Isle of Skye: What have Wyoming and the Isle of Skye got in Common?

Evidence of Scottish Stegosaurs: Scottish Stegosaurs.

The scientific paper: “Diverse vertebrate assemblage of the Kilmaluag Formation (Bathonian, Middle Jurassic) of Skye, Scotland” by Elsa Panciroli, Roger B. J. Benson, Stig Walsh, Richard J. Butler, Tiago Andrade Castro, Marc E. H. Jones and Susan E. Evans published by The Royal Society of Edinburgh/Cambridge University Press.

29 07, 2020

New Study Supports Traditional View of Dinosaur Evolution

By | July 29th, 2020|Adobe CS5, Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Geology, Main Page, Palaeontological articles|0 Comments

Study Suggests that Ornithischian and Saurischian Dinosaurs Evolved Around the Same Time

An international team of scientists from Brazil and Argentina in collaboration with a geochronologist from the Massachusetts Institute of Technology (MIT), have provided evidence to support the hypothesis that the Ornithischia and Saurischia diverged early on in dinosaur evolution and this supports the view of the dinosaur family tree as proposed by Seeley in 1887.

Writing in the journal “Scientific Reports”, the researchers which included Jahandar Ramezani (MIT), re-examined the fossils of Pisanosaurus mertii, dating these fossils to approximately 229 million years ago (Late Carnian stage of the Triassic).  Pisanosaurus is believed to be the earliest known ornithischian dinosaur, although some palaeontologists have concluded that this one-metre-long reptile is a dinosauriform.  This new date suggests that bird-hipped dinosaurs were evolving at around the same as lizard-hipped forms (Saurischia), this challenges the hypothesis proposed by Baron et al in their 2017 paper which re-shaped the traditional view of dinosaur taxonomy.

To read more about the 2017 scientific paper: Root and Branch Reform of the Dinosaur Family Tree.

A View of the Ischigualasto Formation (Foreground)

A view of the The famous Ischigualasto Formation (foreground) the Sierra de Famattina Mountains can be seen on the horizon.

The famous Ischigualasto Formation (foreground), the Sierra de Famattina Mountains can be seen on the horizon (La Rioja province – Argentina).

Picture Credit: Desojo et al

Accurately Dating the Ischigualasto Formation

The researchers focused their fossil finding efforts on the Hoyado del Cerro Las Lajas area, where outcrops of the Ischigualasto Formation can be found, but they are less well explored compared to contemporaneous strata within the “Valley of the Moon” geological park in San Juan Province.  Volcanic deposits yielded zircons at various levels and these minerals permitted the measurement of isotopes of uranium and lead (rate of radiometric decay).  The presence of these igneous rocks allowed the geochronologist to measure the relative proportion of isotopes present in the zircon crystals.  Radiometric dating permitted the scientists to make an estimate of the age of the bedding planes and infer the age of the fossils that they contain.  The study revealed that the Ischigualasto Formation overlaps with the deposition of another important fossil-bearing formation found in North America – the Chinle Formation.

Carefully Jacketing a Specimen Prior to its Removal

Preparing a fossil specimen for removal.

A researcher carefully prepares a field specimen for removal.

Picture Credit: Desojo et al

Overlapping with the Chinle Formation of the South-western United States

The middle layers of the Chinle Formation which outcrops in the south-western part of the USA contain a variety of vertebrate fossils, including early dinosaurs.  However, very few fossils if any, are associated with the lower levels of the Chinle Formation.   The lack for fossils, prevents palaeontologists from understanding more about the early radiation and diversity of the Dinosauria from their suspected origins in the southern hemisphere.  The rocks from which fossils of the  basal ornithischian dinosaur Pisanosaurus have been found were dated to approximately 229 million years ago.  From this data, the research team were able to conclude that the earliest bird-hipped dinosaurs evolved at around the same time as the first lizard-hipped dinosaurs appear in the fossil record.

The Scientists Proposed that Pisanosaurus was Indeed an Ornithischian and it Lived Around 229 Million Years Ago

Pisanosaurus life reconstruction.

A life reconstruction of the Triassic ornithischian Pisanosaurus.

Commenting on the contribution of the dating of the strata to the paper, Jahandar Ramezani stated:

“We can now say the earliest ornithiscians first showed up in the fossil record roughly around the same time as the saurischians, so we shouldn’t throw away the conventional family tree.  There are all these debates about where dinosaurs appeared, how they diversified, what the family tree looked like.  A lot of those questions are tied to geochronology, so we need really good, robust age constraints to help answer these questions.”

Uranium-bearing Zircon Crystals Allowed an Accurate Date for Parts of the Ischigualasto Formation to be Established

Zircon crystals help to date parts of the Ischigualasto Formation in Argentina.

Microscopic crystals of the uranium-bearing mineral zircon were identified in rock samples and these crystals permitted an accurate date for the rock layers to be calculated.

Picture Credit: Desojo et al

Everything Dinosaur acknowledges the assistance of a media release from the Earth, Atmospheric and Planetary Sciences department of MIT in the compilation of this article

The scientific paper: “The Late Triassic Ischigualasto Formation at Cerro Las Lajas (La Rioja, Argentina): fossil tetrapods, high-resolution chronostratigraphy, and faunal correlations” by Julia B. Desojo, Lucas E. Fiorelli, Martín D. Ezcurra, Agustín G. Martinelli, Jahandar Ramezani, Átila. A. S. Da Rosa, M. Belén von Baczko, M. Jimena Trotteyn, Felipe C. Montefeltro, Miguel Ezpeleta and Max C. Langer published in Scientific Reports.

16 07, 2020

Ancient Mega Tsunamis Devastated Doggerland

By | July 16th, 2020|Geology, Main Page, Photos|0 Comments

Massive Tsunamis Devastated Ancient Britain

Scientists led by the University of Bradford have made a major breakthrough in the hunt for confirmation of a historic mega tsunami that is thought to have raged across the North Sea some 8,150 years ago.  Evidence of the catastrophic event has already been found in onshore sediments in Western Scandinavia, the Faroe Isles, north-eastern Britain, Greenland and Denmark but now for the first time, confirmation of the event has been identified on the UK’s southern coasts.

Map Showing the Location of the Storegga Slide

Map outlining the Storegga Slide and subsequent tsunami events.

Map showing location of Storegga Slide in 6,200 BC.

Picture Credit: University of Bradford

The giant tsunami, known as the Storegga Slide, was caused when an area of seabed the size of Scotland (measuring some 80,000 square kilometres and around 3,200 cubic kilometres), shifted suddenly off the coast of Norway.  This triggered huge waves that would have brought devastation to an inhabited ancient land bridge, which once existed between ancient Britain and mainland Europe, a region known as Doggerland, that is now submerged beneath the North Sea.

Professor Vince Gaffney (University of Bradford) explained:

“Exploring Doggerland, the lost landscape underneath the North Sea, is one of the last great archaeological challenges in Europe.  This work demonstrates that an interdisciplinary team of archaeologists and scientists can bring this landscape back to life and even throw new light on one of prehistory’s great natural disasters, the Storegga Tsunami”.

The professor from the University’s School of Archaeological and Forensic Sciences in the Faculty of Life Sciences went onto add:

“The events leading up to the Storegga tsunami have many similarities to those of today.  Climate is changing and this impacts on many aspects of society, especially in coastal locations.”

Finding Traces of the Natural Disaster in the Southern North Sea

It is thought the tsunami, the largest to hit Northern Europe since the end of the last ice age, happened following a period of global climate change.  Until now no clear trace of the tsunami had been found across the southern North Sea and importantly no trace had been found on Doggerland, which was gradually swallowed by rising sea levels after the end of the last glacial maximum.  Indeed, scientists now think the tsunami may even have led to the final inundation of Doggerland.  Cores from an area south of a marine trough named the Outer Dowsing Deep provided nearly half a metre of tsunami-like deposits, stones and broken shells sandwiched between laminated estuarine sediments.  Dating indicated they were contemporary with the Storegga event, while analysis including geochemical, sedimentological, palaeomagnetic, isotopic, palaeobotany and “sedaDNA” (sedentary DNA), techniques showed the deposits could be readily interpreted as resulting from a tsunami.

Area of Ancient Tsunami Research off the Norfolk Coast

Tsumani research area off the Norfolk coast.

Area of research off the Norfolk coast.

Picture Credit: University of Bradford

The study was led by the University of Bradford and collaborators from the University of Warwick, St Andrews University and a number of other academic institutions including the Washington Smithsonian and the London Natural History Museum.

Differentiating a Tsunami Event from Periodic Storm Activity

Evidence for a tsunami event is often difficult to discern from sediment deposition that results from periodic storm activity.  Key to understanding the sequence of events was the interpretation of geochemical signatures of three major waves hitting and retreating from the land.  In a part of the research instigated by the University of Warwick team, the scientists were able to examine how biomass changes with large natural events.

Professor Robin Allaby (University of Warwick) stated:

“This study represents an exciting milestone for sedimentary ancient DNA studies establishing a number of breakthrough methods to reconstruct an 8,150 year old environmental catastrophe in the lands that existed before the North Sea flooded them away into history.”

At the time the tsunami hit Doggerland, a Mesolithic hunter-gather people could have been using the remaining archipelago and for those unfortunate enough to be caught within the tsunami runup zone, it would have been devastating.  However, the palaeo-topography and environmental modelling suggest that much of the landscape may have survived reasonably intact to rapidly return to pre-tsunami conditions.  The longer term fate of these lands was to be submerged as sea level rose to those of the present day.

Professor Vince Gaffney (University of Bradford)

Professor Vince Gaffney (University of Bradford).

Professor Vince Gaffney, 50th Anniversary Chair at the School of Archaeological and Forensic Sciences in the Faculty of Life Sciences at the University of Bradford.

Picture Credit: University of Bradford

Everything Dinosaur acknowledges the assistance of a media release from the University of Bradford in the compilation of this article.

The scientific paper: “Multi-Proxy Characterisation of the Storegga Tsunami and Its Impact on the Early Holocene Landscapes of the Southern North Sea” by Vincent Gaffney, Simon Fitch, Martin Bates, Roselyn L. Ware, Tim Kinnaird, Benjamin Gearey, Tom Hill, Richard Telford, Cathy Batt, Ben Stern, John Whittaker, Sarah Davies, Mohammed Ben Sharada, Rosie Everett, Rebecca Cribdon, Logan Kistler, Sam Harris, Kevin Kearney, James Walker, Merle Muru, Derek Hamilton, Matthew Law, Alex Finlay, Richard Bates and Robin G. Allaby and published in the journal Geosciences.

2 07, 2020

Tiny Dinosaur Eggs from Japan Reveal Small Theropods

By | July 2nd, 2020|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Geology, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

Dinosaur Eggs Provide a View on a “Hidden Ecosystem”

Not all the dinosaurs that ever existed are likely to be named and described by scientists.  Identifying these long extinct creatures relies on there being a fossil record of some sort to study.  A team of researchers writing in the journal “Cretaceous Research”, report on a new Lower Cretaceous fossil egg locality in Hyogo Prefecture, Japan, that provides a tantalising glimpse into a hidden dinosaur dominated ecosystem.

The researchers, which include Kohei Tanaka (University of Tsukuba, Japan) and Darla Zelenitsky (University of Calgary, Canada), describe eggs and eggshell fragments associated with four ootaxa, two of which are new to science.  The site reveals a hidden diversity of small dinosaurs, particularly non-avian theropods, in the Hyogo region and indicates the area was utilised for nesting by various small dinosaur species in the Early Cretaceous.

The Newly Erected Ootaxa Himeoolithus murakamii the Most Abundant Ootaxa from the Quarry Site

Himeoolithus murakamii a new ootaxa from Japan.

Himeoolithus murakamii egg fossil, high resolution image, line drawing of egg showing elongated shape and life reconstruction.

Picture Credit: University of Tsukuba and Museum of Nature and Human Activities Hyogo Prefecture with life reconstruction by Ayaka Nagate

The Kamitaki Locality

The fossil site, known as the Kamitaki locality lies close to the  Sasayama River in Kamitaki, Sannan-cho, Tamba City,  Hyogo Prefecture.  One horizon has yielded a variety of small vertebrate fossils including frogs and lizards, plus a partial tail from a titanosaur that was formally named and described in 2014 (Tambatitanis amicitiae).  Eggshell fragments are also associated with this part of the site.  However, a horizon some 5.5 to 6.75 metres above the bonebed layer has yielded an astonishing quantity of egg fossils, including a nearly complete egg, several partial eggs and hundreds of eggshell fragments.  The researchers conclude that this horizon represents a nesting area in which a variety of small theropods raised their young.

As a result of this research, two new theropod egg taxa have been named – Himeoolithus murakamii and Subtiliolithus hyogoensis.  Although no skeletal remains of these little dinosaurs have been found, the presence of all the egg fossils suggests that there were numerous different types of small theropod co-existing in this ancient ecosystem.

The Location of the Fossil Site within Hyogo Prefecture

Fossil site location.

The location of the Kamitaki fossil site.

Picture Credit: University of Tsukuba and Museum of Nature and Human Activities Hyogo Prefecture/Cretaceous Research with additional annotation by Everything Dinosaur

The mudstone deposits are thought to have been laid down around 110 million years ago (Albian faunal stage of the Lower Cretaceous) and the palaeoenvironment has been described as floodplain which was subjected to a extremes of seasonality with long periods of very dry conditions punctuated by a very wet season that led to flood events.

The most abundant ootaxon at the quarry, Himeoolithus, is represented by four eggs and over 1300 scattered eggshell fragments. Himeoolithus accounts for over 96% of all the egg fossils associated with this site.  Himeoolithus is the smallest non-avian theropod egg known to date, the scientists estimate that the egg probably weighed about as much as a quail egg (around 9.9 grammes).  It is also a very unusual shape, being elongate with its length 2.25 times its width (length : width ratio 2.25).  The new egg fossil horizon was discovered in 2015 and was mapped and intensively excavated in the winter of 2019.  In total, the egg fossil horizon and the lower Kamitaki Bonebed (Ohyamashimo Formation), have yielded six small theropod ootaxa.

The Stratigraphy of the Kamitaki Locality and Examples of Associated Ootaxa

Stratigraphy of the Kamitaki locality with examples of theropod ootaxa from the site.

The stratigraphy of the Kamitaki locality with examples of theropod ootaxa from the site.  Subtiliolithus hyogoensis is the second of the new ootaxa to be reported in the scientific paper.

Picture Credit: University of Tsukuba and Museum of Nature and Human Activities Hyogo Prefecture/Cretaceous Research

Notable Biodiversity

The ootaxa demonstrate that this ancient habitat was home to a variety of small theropod dinosaurs.  It is likely that many other palaeoenvironments associated with the Lower Cretaceous were also home to a diverse variety of small theropods too, these animals being currently under-represented in the fossil record.

Lead author of the paper, Professor Kohei Tanaka, confirmed that the research team thought that the new egg fossil horizon was a nesting site and the deposit was not the result of a transportation and subsequent burial of egg material from another location:

“Our taphonomic analysis indicated that the nest we found was in situ, not transported and redeposited, because most of the eggshell fragments were positioned concave-up, not concave-down like we see when eggshells are transported.”

The professor added:

“The high diversity of these small theropod eggs makes this one of the most diverse Early Cretaceous egg localities known.  Small theropod skeletal fossils are quite scarce in this area.  Therefore, these fossil eggs provide a useful window into the hidden ecological diversity of dinosaurs in the Early Cretaceous of south-western Japan, as well as into the nesting behaviour of small non-avian theropods.”

Everything Dinosaur acknowledges the assistance of a media release from the University of Tsukuba (Japan), in the compilation of this article.

The scientific paper: “Exceptionally small theropod eggs from the Lower Cretaceous Ohyamashimo Formation of Tamba, Hyogo Prefecture, Japan” by
Kohei Tanaka, Darla K. Zelenitsky, François Therrien, Tadahiro Ikeda, Katsuhiro Kubota, Haruo Saegusa, Tomonori Tanaka and Kenji Ikuno published in the journal Cretaceous Research.

1 06, 2020

Protoceratops was a Very Tough Dinosaur

By | June 1st, 2020|Adobe CS5, Dinosaur Fans, Everything Dinosaur Products, Geology, Main Page, Photos of Everything Dinosaur Products|0 Comments

Protoceratops Lived in a “Stressed” Environment

Everything Dinosaur team members are currently putting together a short video review of the new Wild Past Protoceratops (P. andrewsi) dinosaur model.  Our intention in the video is to discuss the model and also to talk about the genus upon which the figure is based.  After all, Protoceratops is one of the most studied of all the dinosaur genera known to science.  However, “first horned face” can still throw up a few surprises.  For example, the size of its orbit (eye socket), suggests the Protoceratops had disproportionately large eyes compared to other ceratopsians.  Could Protoceratops have been nocturnal?

Size Comparison (Protoceratops andrewsi)

How big was Protoceratops andrewsi?

Protoceratops andrewsi was a relatively small dinosaur but it was one of the larger vertebrates associated with the Bayn Dzak (Flaming Cliffs) locality.  Could it have been nocturnal?

Picture Credit: Everything Dinosaur

Protoceratops was a Tough Dinosaur!

Intriguingly, when the dinosaur fossil specimens collected by the Central Asiatic Expeditions from 1922-1925 (the expeditions led by Roy Chapman Andrews and Walter Granger of the American Museum of Natural History), from the Flaming Cliffs locality are totted up, over 90 percent of them represent Protoceratops andrewsi.  The Flaming Cliffs are the type locality for the Djadokhta Formation.  Something like 108 individual dinosaur specimens were collected by the American Museum of Natural History field teams between 1922 and 1925, all but seven of them represented Protoceratops andrewsi.  Preservational bias has been largely ruled out, it is therefore likely that Protoceratops was common in this habitat.  However, both the Djadokhta Formation and the potentially contemporaneous Bayan Mandahu Formation, where the fossils of the second Protoceratops genus were found (P. hellenikorhinus), represent arid, desert-like palaeoenvironments.

Both Protoceratops species lived in extremely harsh conditions, an idea supported by the lack of diversity and the absence of large animals from the fossil record of both Djadokhta and Bayan Mandahu.

A Lack of Diversity and Few Large-bodied Dinosaurs Associated with Bayn Dzak (Flaming Cliffs Type Locality) of the Djadokhta Formation

The dinosaur biota associated wit the Djadokhta Formation.

The biota associated with the Protoceratops dominated Djadokhta Formation.  Evidence that Protoceratops lived in a stressed environment with few resources.  We have used a picture of the Wild Past Protoceratops dinosaur model to indicate the presence of Protoceratops.

Picture Credit: Everything Dinosaur

Comparing the Djadokhta Formation and the Nemegt Formation Dinosaur Biotas

The lack of large-bodied dinosaurs and the limited number of different types of dinosaur are highlighted when these geological formations are compared to the Nemegt Formation dinosaur biota.  The strata that forms the Nemegt Formation was formed in a much wetter more verdant environment.

Hadrosaurs, Titanosaurs, Ankylosaurids and Large Theropods Dominate the Nemegt Formation Dinosaur Biota

The Nemegt Formation contains the fossils of many dinosaurs.

The dinosaur biota associated with the Nemegt Formation.  Many different dinosaurs are reported from the Upper Cretaceous Nemegt Formation.  The presence of large herbivores such as therizinosaurs, titanosaurs and duck-billed dinosaurs is significant.

Picture Credit: Everything Dinosaur

The lack of diversity and the absence of large-bodied vertebrates from the Bayn Dzak location indicates that Protoceratops inhabited a stressed environment.  Protoceratopsid fauna is associated with sediments from semi-arid, to desert regions formed from aeolian deposits in the main.  During the time that the Djadokhta and the Bayan Mandahu Formations were being formed, much of central Asia was characterised by an extensive sandy desert with little surface water.

Protoceratops may have been quite small, but it was a very tough and hardy dinosaur.

To see the article that features an early Wild Past Protoceratops dinosaur model video made by Everything Dinosaur: Wild Past Protoceratops Video Showcase.

To purchase the Wild Past Protoceratops figure: Wild Past Protoceratops dinosaur model.

30 05, 2020

Doomsday Scenario for the Non-avian Dinosaurs

By | May 30th, 2020|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Geology, Main Page|0 Comments

Dinosaur-dooming Bolide Struck Earth at Worst Possible Angle

The extra-terrestrial object, whether it was a comet or an asteroid, that devastated our planet some sixty-six million years ago, struck Earth at the “deadliest possible” angle according to new research published this week in the journal Nature Communications.  Computer simulations created by researchers based at Imperial College London indicate that the huge object struck Earth at an angle of 45 to 60 degrees to the horizontal.  This maximised the amount of climate-changing gases that were thrust into the upper atmosphere.

An Artist’s Impression of the Moments before the Extra-terrestrial Bolide Impact

The end of the non-avian dinosaurs.

An artist’s impression of the bolide about to impact with the Gulf of Mexico 66 million years ago.

Picture Credit: Chase Stone

The Significance of the Impact Trajectory

The severity of an extra-terrestrial impact is influenced by a number of factors.  For example, the size and the mass of the bolide, the speed of the impact and the trajectory and direction of impact.  The impact direction and the angle of the collision affect the amount of ejector that is thrown up into the atmosphere.  For the non-avian dinosaurs, it was a question of a number of factors that exacerbated the mass extinction event.  Although there has been a considerable amount of research carried out on Chicxulub crater the impact trajectory remains controversial.  The use of three-dimensional computer simulations along with geophysical observations suggests that the crater was formed by a steeply-inclined impact from the northeast.  Such a strike likely unleashed billions of tonnes of sulphur.  The sulphur would have reacted with the oxygen and other elements to form acid rain which would then have fallen to Earth and further devastated the environment.  The debris in the atmosphere would have blocked out the sun and triggered a nuclear winter effect.  This catastrophe led to the extinction of 75% of life on Earth.

The simulations were performed on the Science and Technology Facilities Council (STFC) DiRAC High Performance Computing Facility.

Plotting a Momentous Few Minutes in the History of Planet Earth

Plotting the Chicxulub Impact Event

The team used computer simulations and geophysical data to recreate the Chicxulub impact event.  The computer simulations permitted the researchers to map the entire crater formation event in unprecedented detail.

Picture Credit: Imperial College London/Nature Communications

Lead author of the scientific paper, Professor Gareth Collins of the College’s Department of Earth Science and Engineering stated:

“For the dinosaurs, the worst-case scenario is exactly what happened.  The asteroid strike unleashed an incredible amount of climate-changing gases into the atmosphere, triggering a chain of events that led to the extinction of the dinosaurs.  This was likely worsened by the fact that it struck at one of the deadliest possible angles.”

The Crater Creation

The top layers of rock around the Chicxulub crater in the Yucatan peninsula contain high amounts of water as well as porous carbonate and evaporite material.  When disturbed and greatly heated by the energy of the impact, these rocks would have been vaporised flinging huge amounts of the greenhouse gas carbon dioxide, sulphur and water vapour into the atmosphere.  The sulphur and other particles would have formed aerosols as well as acidifying the atmosphere.  These aerosols would have blocked out sunlight stopping photosynthesis and leading to the collapse of food chains.  The world would have been plunged into a nuclear winter.

A Geophysical Map of the Impact Crater

Gravity map of the Chicxulub crater.

A geophysical gravity map showing the outline of the Chicxulub crater and its surrounding environment.

Picture Credit: Imperial College London/Nature Communications

Working in collaboration with colleagues from the University of Freiburg (Germany) and the University of Texas at Austin the impact event was re-created in extensive detail, which will help scientists to better understand impact craters on our own planet as well as those found elsewhere within the solar system.  Crucial to determining the angle and direction of the impact was the relationship between the centre of the crater, the centre of the peak ring (a circle of mountains made of heavily fractured rock inside the crater rim) and the centre of dense, uplifted mantle rocks.

Co-author of the scientific paper, Dr Auriol Rae (University of Freiburg) added:

“Despite being buried beneath nearly a kilometre of sedimentary rocks, it is remarkable that geophysical data reveals so much about the crater structure, enough to describe the direction and angle of the impact.”

Everything Dinosaur acknowledges the help and assistance of a media release from Imperial College London in the compilation of this article.

The scientific paper: “A steeply-inclined trajectory for the Chicxulub impact” by G. S. Collins, N. Patel, T. M. Davison, A. S. P. Rae, J. V. Morgan, S. P. S. Gulick, IODP-ICDP Expedition 364 Science Party and Third-Party Scientists published in Nature Communications.

24 05, 2020

The Most Dangerous Place and Time in the Cretaceous

By | May 24th, 2020|Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Geology, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

A Comprehensive Guide to the Fossils from the Kem Kem Beds of Eastern Morocco

A team of international researchers have documented the fossil vertebrates associated with the early Late Cretaceous (Cenomanian-Turonian) of the famous Kem Kem beds of eastern Morocco.  They conclude that with the abundance of hypercarnivores such as Spinosaurus, abelisaurids, Carcharodontosaurus and Deltadromeus, several large pterosaurs and a multitude of giant fish and crocodyliforms, no comparable modern terrestrial ecosystem exists with a similar bias toward large-bodied carnivores.

Arguably, the sediments that make up the Kem Kem Group, which is composed of the lower Gara Sbaa and upper Douira formations, represent the most dangerous place and time in the whole of the Cretaceous.

Examples of Theropod Teeth Associated with the Kem Kem Group of Eastern Morocco

Indeterminate theropod teeth from the Kem Kem Group.

Indeterminate theropod teeth from the Kem Kem Group with (H) showing the denticles of (F) and (N) close up view of denticles in (M).  Scale bar equals 2 cm in A-C and I-M whilst 3 cm in D and 5 mm in H and N.

Picture Credit: Ibrahim et al (ZooKeys)

An Ambitious Target

The researchers which included Nizar Ibrahim and Paul Sereno (University of Chicago), David Unwin (University of Leicester), Samir Zouhri (Université Hassan II, Casablanca, Morocco) and David Martill (University of Portsmouth), had an ambitious objective.  The scientists set out to document and summarise the taxonomic status of the fauna that had been described based on the major collections of Kem Kem fossils, as well as to report on the geological age of the various strata and to plot the palaeoenvironment of this part of north Africa during the early stages of the Late Cretaceous.

The team’s comprehensive report has been published with free access in the journal ZooKeys.

The Changing Palaeoenvironment Represented by the Kem Kem Group Sediments

The palaeoenvironment of the Kem Kem Beds.

Schematic paleoenvironmental stages depicting the Kem Kem region during the Cretaceous.  Stages: (1) wide rivers, (2) large river systems with substantial sandbanks, (3) deltaic conditions and (4) rise of the limestone platform.

Picture Credit: Ibrahim et al (ZooKeys)

A Very Dangerous Place to Be (Large Crocodyliforms and Pterosaurs)

The strata have provided evidence of large number of crocodyliforms from one-metre-long insectivores, herbivorous forms to giant predators such as Sarcosuchus imperator.  Several different types of pterosaur are also associated with these deposits.  The first pterosaur remains recovered consisted of isolated teeth collected in the late 1940s and early 1950s but at the time their affinity with the Pterosauria was not recognised.  For an article from Everything Dinosaur about recent pterosaur discoveries from Morocco: Pterosaurs, Pterosaurs and Even More Pterosaurs.

Cervical Vertebra (Bone from the Neck) Ascribed to an Azhdarchid Pterosaur

Third cervical? attributed to an azhdarchid pterosaur.

Near complete third cervical? of an azhdarchid pterosaur from the Kem Kem Group.  FSAC-KK 3088 in (A) ventral, (B) dorsal, (C) right lateral, (D) left lateral, (E) anterior and (F) posterior view.  Scale bar equals 5 cm.

Picture Credit: Ibrahim et al (ZooKeys)

In addition, the first tapejarid pterosaur from Africa was reported recently (Afrotapejara zouhrii), the trivial name honours Professor Samir Zouhri, one of the authors of the extensive review.  To read an article about Afrotapejara: The Fourth New Moroccan Pterosaur – Afrotapejara.

Lots and Lots of Dinosaurs – A Bias Towards the Theropoda

Dinosaurs are strongly associated with these strata, but there is only very fragmentary evidence of Ornithischians including a single, large footprint.  This suggests that bird-hipped dinosaurs were present but, in contrast to most other Cretaceous biotas, they seem very much underrepresented by the fossil material.  Sauropods such as the rebbachisaurid Rebbachisaurus garasbae and titanosaurs are known from both the Douira and Gara Sbaa formations, however, it is theropod specimens that dominate the Dinosauria associated with the Kem Kem Group.  There is evidence to support one medium-sized to large Kem Kem abelisaurid and the discovery of single neck bone (cervical vertebra) indicates a Noasauridae presence.

Huge hypercarnivores such as Carcharodontosaurus saharicus and Spinosaurus aegyptiacus have been reported.  The habitat seemed to have an overabundance of large, carnivorous dinosaurs, although extensive niche partitioning is proposed by several authors.

Perhaps the Most Famous African Dinosaur of them all – Spinosaurus aegyptiacus

Spinosaurus aegyptiacus skull and skeleton.

Skull and skeletal reconstruction of Spinosaurus aegyptiacus.  Scale bars equal 40 cm in A and B, whilst in C the scale bar is 1 metre.

Picture Credit: Ibrahim et al (ZooKeys)

Deltadromeus agilis

One of the most mysterious of all the theropods from Morocco is Deltadromeus agilis.  The taxonomic position of this meat-eater remains controversial.  A partial skeleton (UCRC PV11), was discovered in a coarse sandstone layer in the upper portions of the Gara Sbaa Formation.  The bones were found in association with teeth of the huge sawfish Onchopristis as well as teeth from crocodyliforms.  Fossils associated with D. agilis from eastern Morocco show a resemblance to isolated material recovered from the roughly contemporaneous Bahariya oasis in the Western Desert of Egypt by the German palaeontologist Ernst Stromer.  The Egyptian fossils were assigned to the taxon Bahariasaurus ingens, but the Moroccan and Egyptian material could represent the same genus.  If this is the case, then D. agilis would become a senior synonym of B. ingens.  A single thigh bone from the Bahariya oasis measures 144 cm long.  This suggests that whatever sort of carnivore Deltadromeus/Bahariasaurus was, it was huge.  Some commentators have suggested that based on femur proportions Deltadromeus could have been only slightly shorter (but more lightly built), than Tyrannosaurus rex.

Holotype of D. agilis (A)  and Compared in Size to the Egyptian Femur Specimen (B)

Deltadromeus agilis skeleton reconstruction.

Deltadromeus agilis from Morocco and Egypt.  A (A) revised reconstruction based on UCRC PV11 (B) holotype compared to a large femur (now lost) referred to the genus and species from the Bahariya Formation, Egypt.  Known elements in white.  Scale bars: 1 m.

Picture Credit: Ibrahim et al (ZooKeys)

Sadly, like much of Stromer’s material from the Egyptian expeditions, the femur has been lost.

It is very likely that there were lots of smaller predatory dinosaurs too. Dromaeosaurid teeth have been reported from several localities but bones are exceptionally rare and the only positively identified dromaeosaurid skeletal elements are some foot bones found in Sudan and recovered from Cenomanian-age rocks.

A Predominance of Aquatic Predators

The authors state that the Kem Kem assemblage is dominated by aquatic and subaquatic invertebrates and vertebrates, the majority of which are predators. They suggest that as most of the taxa are exploiting aquatic food resources, then like modern marine food chains, the habitat is predator dominated.  As to the overabundance of carnivorous dinosaurs compared to plant-eating ones, the researchers conclude that this is not due to sampling bias or preservation factors.  Large theropods in the food web were supported primarily in the case of Spinosaurus or secondarily in the case of the terrestrial carnivores by the huge amount of aquatic protein sources.

The dissected deltaic plain and nearshore environments may have enhanced aquatic resources while limiting, or rendering patchy areas of available vegetation for large-bodied dinosaurian herbivores. Hence the bias towards carnivores when it comes to assessing the fossilised remains of dinosaurs from the Kem Kem beds.

The Presence of So Many Carnivores could be Explained by the Abundance of Aquatic Food Sources such as Small Fish

Serenoichthys kemkemensis from the Douira Formation.

Serenoichthys kemkemensis from the Douira Formation.  Scale bar equals 1 cm.  The abundance of predators could be explained by the large amount of aquatic protein sources present in the environment.

Picture Credit: Ibrahim et al (ZooKeys)

The scientific paper: “Geology and paleontology of the Upper Cretaceous Kem Kem Group of eastern Morocco” by Nizar Ibrahim, Paul C. Sereno, David J. Varricchio, David M. Martill, Didier B. Dutheil, David M. Unwin, Lahssen Baidder, Hans C. E. Larsson, Samir Zouhri and Abdelhadi Kaoukaya published in ZooKeys.

23 05, 2020

The Principle of Superposition

By | May 23rd, 2020|Educational Activities, Geology, Main Page, Teaching|0 Comments

Explaining The Principle of Superposition

Everything Dinosaur received an enquiry earlier this week from a young student studying rocks and fossils at their school as part of a geology project.  The student asked, “what is the law of superposition?” Our team members were happy to provide a short explanation.

The principle of superposition, often referred to as the law of superposition is an observation that sedimentary layers of rock at the bottom of a sequence if they undeformed, then they must be older than those at the top.  The bottom layers must have been in existence in order to permit the upper layers to have been deposited on top of them.

Layers of Sedimentary Rock Demonstrating the Principle of Superposition

The Church cliffs at Lyme Regis.

Fossil hunting can be fun but beware of the cliffs.  The Church cliffs at Lyme Regis are notoriously unstable and dangerous but they do help to demonstrate the law of superposition.

Picture Credit: Everything Dinosaur

A Fundamental Principle of Geology

The law of superposition is regarded as one of the fundamental principles that underpins modern geology, although this principle is very much applicable in other research fields such as archaeology.  It helps to provide a basis for the relative dating of strata.  As the oldest strata will always be found at the bottom of an undeformed, observable sequence of sedimentary rocks.  It is extremely helpful when considering stratigraphical dating, which is governed by the proposition that a layer cannot be older than its constituents.

The introduction of this principle is accredited to the Danish polymath Nicolas Stenos (1638-1686), often referred to as the “father of modern geology”.  In 2012, Nicolas Stenos was honoured with the creation of a Google doodle demonstrating his principle complete with illustrations of fossils.

The 2012 Google Doodle Honouring Nicolas Stenos

Remembering the Contribution of Nicolas Stenos.  Danish scientist honoured with a Google doodle.

Picture Credit: Google

This geological principle was popularised by the famous English geologist William Smith (1769-1839), who used this law to create the first ever map showing the geology of a landscape.  In 1815, the year of the battle of Waterloo, William Smith published a map outlining the geology of England, Wales and parts of Scotland.

The “Ground-breaking” First Geological Map to be Published

The William Smith Geological Map (1815).

Can you see the geology in your part of the world?

Picture Credit: The Geological Society of London

22 05, 2020

13,000 Edmontosaurus Bones and Counting

By | May 22nd, 2020|Adobe CS5, Dinosaur and Prehistoric Animal News Stories, Dinosaur Fans, Geology, Main Page, Palaeontological articles, Photos/Pictures of Fossils|0 Comments

Massive Edmontosaurus Bonebed Provides Data on Dinosaur Decomposition

A team of scientists have produced a study mapping an astonishing dinosaur bonebed that has so far yielded a staggering total of 13,000 individual fossil elements.  In truth, the bonebed contains many more fossils, but individual dinosaur teeth, ossified tendons and other fragmentary elements under five centimetres in length have not been counted.  The site is located in eastern Wyoming and consists almost entirely of the preserved remains of a single type of dinosaur, a hadrosaur (Edmontosaurus annectens).  The bonebed study has not only provided a great deal of information about this duck-billed dinosaur but shed light on how death assemblages consisting of a large number of corpses are formed and how various bones of differing sizes might be transported before final deposition.

Dinosaur Bonebeds such as the Danek Edmontosaurus regalis Bonebed in Edmonton Have Yielded Thousands of Fossil Bones

Excavating an Edmontosaurus.

The Danek Edmontosaurus bonebed is typical of an Edmontosaurus-dominated bonebed which are widespread in the Upper Cretaceous (Campanian to Maastrichtian) of western North America).

Picture Credit: Victoria Arbour

The Hanson Ranch Bonebed (Lance Formation)

Writing in the on-line, open access journal PLOS One, the scientists which include Keith Synder of the Biology Dept. of the Southern Adventist University, Tennessee, document the taphonomy and depositional history of an extensive E. annectens bonebed known as Hanson Ranch, in the Lance Formation of eastern Wyoming.  The bonebed includes five main quarries and three exploratory quarries.  Approximately 13,000 elements including around 8,400 identifiable bones, have been recovered in 506 square metres of excavated area in twenty years (1996-2016).

Virtually all the fossils are located within a fine-grained (claystone to siltstone) bed that has a maximum depth of two metres.

Mapping the Stratigraphy of the Main Bonebeds at the Hanson Research Station (Wyoming)

The Stratigraphy of the Hanson Research station.

Local stratigraphy associated with the main bonebeds at the Hanson Research station.  The green arrow indicates position of main bonebed.

Picture Credit: Synder et al (PLOS One) with additional annotation by Everything Dinosaur

An Excellent State of Preservation

Almost all the fossils recovered from the site exhibit exquisite preservation with little or no abrasion, breakages or signs of weathering prior to deposition.  All the material is disarticulated and scattered although over a relatively confined area.  This evidence in conjunction with analysis of the sediments associated with the fossils indicates that the bones were moved and buried after a period of initial decay and decomposition of the Edmontosaurus carcasses.

Mapping the Distribution of Fossil Bones in a Bonebed

A map showing the distribution of fossil material in an Edmontosaurus bonebed.

A map showing typical disarticulated fossil bone distribution in a bonebed.

Picture Credit: Synder et al (PLOS One)

Gaining a Better Understanding of Edmontosaurus Biostratigraphy

The thousands of fossil bones represent mainly adult or sub-adult specimens.  Due to the huge number of fossils associated with the Hanson Research site, the scientists have been able to gain a deeper understanding of Edmontosaurus biostratigraphy including how elements from the skeleton can be transported over distances prior to deposition.  The most abundant fossil bones are ischia, pubes, scapulae, ribs and limb bones.  In contrast, vertebrae, ilia and chevrons are rare.

When it comes to cranial material lower jaw bones (dentaries), nasals, quadrates and jugals are prevalent whilst premaxillae (upper jaw bones), predentaries and bones associated with the braincase are seldom found.  The researchers suggest that following decay and break-up of the carcase, water action sorted and removed the articulated sections such as the backbone and the smaller bones such as the digits and toes, before, or at the same time, the remaining material was swept up in a subaqueous debris flow that created the final deposit.

The scientists suggest that similar processes may have been at work that created the other hadrosaurid-dominated Upper Cretaceous bonebeds associated with such geological formations as Hell Creek, Two Medicine, Horseshoe Canyon, Prince Creek as well as the Lance Formations of western North America.  It is noted that there is a remarkably similar skeletal composition among the fossil bonebeds studied.  It is also noted that there is a significant correlation between the hadrosaurid bonebeds and fluvial assemblages representing thanatocoenosis* events seen with modern-day vertebrate death assemblages.

Thanatocoenosis* Explained

Thanatocoenosis refers to a site where a collection of fossils representing a variety of organisms are found together.  Such sites are often referred to as death assemblages.  The organisms represented at the location may not have been associated in life, but their remains have been transported and deposited together thus forming a fossil bed composed of an extensive amount of fossilised material.

Not All of the Dinosaur Fossils are Edmontosaurus

The bonebed can be described as monodominant as the vast majority of the fossil material found can be assigned to just one species Edmontosaurus annectens.  Non-dinosaurian terrestrial taxa identified include mammals and squamates along with the remains of many aquatic creatures such as crocodiles, turtles, gar and other fishes and numerous molluscs.  Some other types of plant-eating dinosaur are represented notably, ceratopsids, pachycephalosaurs, nodosaurs and members of the family Thescelosauridae.  Numerous shed theropod teeth are also associated with this location.  Everything Dinosaur will post up a separate article detailing one rather special theropod fossil associated with a quarry close to the Hanson Research station in the near future.

A Life Reconstruction of the Hadrosaurid Edmontosaurus

Wild Safari Prehistoric World Emontosaurus model.

The new for 2020 Wild Safari Prehistoric World Edmontosaurus dinosaur model.

Picture Credit: Everything Dinosaur

The scientific paper: “Over 13,000 elements from a single bonebed help elucidate disarticulation and transport of an Edmontosaurus thanatocoenosis” by Keith Snyder, Matthew McLain, Jared Wood and Arthur Chadwick published in PLOS One.

18 05, 2020

Tiny Crystals Can Stop Contaminants in their Tracks

By | May 18th, 2020|Adobe CS5, Geology, Main Page|0 Comments

Tiny Crystals Plug Gaps Limiting the Uptake of Contaminants in Rocks

Research published today by a UK-based team of scientists has shown for the first time that the mobility of potentially harmful contaminants in crystalline rocks over long periods of time may be severely limited due to the presence of tiny crystals, meaning contaminant movement is likely to be focused to water-bearing fractures only.  Movement of contaminants through rocks below ground can act to spread contamination, an issue relevant to the geological disposal of some wastes.  Scientists and academics undertake studies to enhance their understanding of how this process works, helping to reduce uncertainties and to assess potential environmental risks.

These new results shed light on the difficult problem of how contaminants may move over extremely long time periods and should improve our ability to calculate long term risks.  This study, published in the academic journal “Scientific Reports”, examined crystalline (granite) rock samples from an underground system in Japan (Upper Cretaceous Toki Granite) and the results imply that in many cases the importance of “rock matrix diffusion” may be minimal.  Additional analyses of a contrasting crystalline rock system (Carnmenellis Granite, from the UK) confirm and corroborate these results.

The Japanese samples were taken from the Toki Granite pluton which was formed around 70 million years ago.

CT-Scans Permitted the Researchers to Map Voids and Fractures in the Granite Samples

Pore space analysis in the igneous rocks.

Pore sizes and pore distributions within the Toki and Carnmenellis granite proximate to primary fractures (indicated by solid blue regions at upper surfaces) as determined via X–ray CT analysis.

Picture Credit: Wogelius et al published in “Scientific Reports”

These findings, which apply to long-lived systems, build on previous field studies and laboratory assessments over short periods of time which also suggested that contaminant mobility in crystalline rocks, such as granite, will be limited to short distances in parts of the rock that are away from large fractures.  This new work has examined rocks from ancient crystalline rock systems in Japan and the UK to show that even over immensely long periods of geological time the movement of elements within such crystalline rock is indeed small, in large part because the formation of large quantities of small crystals during the aging of the rock acts to seal small openings and limit fluid access to only a few millimetres of the rock bordering fractures.

Professor Roy Wogelius, the senior author on this paper, commented:

“We set out to test exactly what we could resolve in terms of fluid access to the matrix of these rocks and we were amazed at the extremely limited volume involved.  But what was most amazing to us was the distribution of tiny crystals of carbonate minerals throughout what we usually think of as a uniform block of crystalline rock.  Here, unexpected little crystals of calcite appear throughout the rock plugging up all the tiny openings.  These crystals clog everything up and keep most of the fluid in large cracks with no access to smaller openings.  This effectively shuts down contaminant access to the rock mass, meaning any contaminant movement would likely focus in rock fractures only. “

This study in combination with other collaborative research projects will help geologists to produce more accurate models of how pollutants and other contaminants can persist in the environment and threaten groundwater.

The work was completed by researchers from UK academia (The University of Manchester and the University of Leeds), in partnership with the British Geological Survey, two environmental consultancies – Quintessa and NSG – and was funded as part of collaborative work with the UK organisation Radioactive Waste Management.

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

The scientific paper: “Mineral reaction kinetics constrain the length scale of rock matrix diffusion” by R. A. Wogelius, A. E. Milodowski, L. P. Field, R. Metcalfe, T. Lowe, A. van Veelen, G. Carpenter, S. Norris and B. Yardley published in Scientific Reports.

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