Dinosaurs on the Isle of
Wight
In April of 2001 we were approached by the BBC (British Broadcasting Corporation) to
assist them in delivering a series of programmes “Live From Dinosaur Island!”- going out mostly live for
five nights in the last week of June 2001 - based around digging up dinosaur fossils on
the Isle of
Wight (off the South Coast of the UK). The Isle of Wight provides a fantastic location
for any geological or palaeontological fieldtrip due to its wealth of
well-exposed geological sections which cover a wide variety of geological time
periods. In particular the Island is known as one of the best sites in Europe
for dinosaur fossils, and many have been found there recently. Six coastal
sites were selected by the BBC with the kind help of local, dedicated, amateur
collectors where the bones of dinosaur skeletons had been systematically
collected recently and were likely to yield further good results.
We were happy not only to provide advice on
logistics concerning retrieving the fossil remains and on cleaning and
conserving the finds, but also to organise personnel and to purchase, hire, or
organise the loan of, all the equipment, tools, and consumables for cleaning
and conserving the fossils. We provided many of the tools and pieces of
equipment ourselves, located some technical conservation equipment which we
were loaned at no charge, and hired other technical equipment at a
substantially reduced rate. We also advised on a suitable system for recording
the finds at each of the excavations and purchased all the necessary items –
bearing in mind we were expecting to have dozens of finds from six separate
sites! We made rigid wooden stretchers covered in hand-made large, flat
sandbags upon which to remove the larger, more fragile, bones from the beach.
We also mixed the relevant consolidants and adhesives from the basic chemicals
(only using materials considered to be the most tried, tested and stable) that
would be necessary for repairing and strengthening the fossil bones that are so
often found in dozens or hundreds of fractured pieces. We provided COSHH
(Control of Substances Hazardous to Health) forms and drew up risk assessments
for all involved to read and sign. We were able to source very well qualified
and experienced museum professionals who were happy to volunteer to assist us
in cleaning and conserving the fossil remains.
Collecting dinosaurs on the Isle of Wight:
Three photos showing the beautiful cliffs and beaches of the Isle of Wight and a very large Iguanadon footprint cast. This was created by an Iguanadon’s three-toed foot stepping into the mud 120-odd million years ago and being in-filled naturally with deposits that eventually fossilised harder than the surrounding sediment. Note the adult hand as scale!
Pictures from behind the scenes whilst filming was taking place:
For more information about this
project click on the following selections - the geology of the
area, recent
dinosaur finds, suggested reading, cleaning and
conserving the fossils and equipment and supplies.
Because the Isle of Wight is an island made up of layers of sedimentary rock and is fortunately hilly there are numerous cliff exposures with easily accessible fossil-rich geology. These cliffs represent a very wide variety of conditions and time periods in the Earth’s history between 35 and 120 million years ago, making the Island an excellent area to visit for anyone who is studying geology, palaeontology, or general earth sciences. There are numerous localities for Cretaceous chalk and greensand fossils and for Palaeogene, Oligocene and Quaternary fossils also. Dinosaur remains and other associated fossils are found only in the layers of sediment on the western side of the Island that were lain down in the Lower Cretaceous period between 110 to 130 million years-ago. These red and green freshwater marls (mudstones and sandstones) were deposited by rivers that were part of an estuary system that stretched from southern England, across northern France, to Belgium long before the English Channel existed. These layers, collectively called “The Wealden”, are the oldest sediments on the island and, as well as dinosaurs, contain rare remains of pterosaurs, crocodiles, turtle, fish and other creatures and the occasional coprolite, (fossil dropping), amber fragment, foot-print cast, or gastrolith (stomach-stone used to aid breaking up food). Much less rare and large amounts of poorly fossilised plant debris,
Even though the Isle of Wight and the South of England are the best locations in the world for early Cretaceous dinosaurs, dinosaur finds here are still relatively rare. To find anything other than a small, probably water-worn, fragment one has to persist in spending a great deal of time and patience walking the beaches, and to do enough research so that you know what you are looking for and where it is likely to be. Of the different types of dinosaurs that have been found here over the years, the most numerous are the famous hypsilophodons and iguanadons. The ornithischian herbivorous “hypsilophodons” (meaning “high-ridged tooth”) were small, long legged, 3 to 8 feet-long, fleet-footed dinosaurs with short arms and a horny beak e.g. Hypsilophodon foxii. The ornithischian “Iguanadons” (meaning “iguana–tooth”) were larger, heavier, 30 foot-long herbivores e.g. Iguanadon bernissartensis and Iguanadon atherfieldensis.
· Recent dinosaur finds:
- Eotyrannus lengi: (meaning
“early tyrant", and named after collector Gavin Leng). A 15-foot-long carnivorous dinosaur - a fast,
agile predator, preying on species such as Valdosaurus and Hypsilophodon. The
first bones of were found in 1997, and it took four years to excavate the site,
finding 40 percent of the skeleton, and to analyze the findings. Various features including the skull,
shoulder blades, and the configuration of the teeth proved it to be a primitive
member of the Tyrannosaurid group, a
previously unknown relative of Tyrannosaurus
rex. It is an important piece
in the evolutionary jigsaw of Tyrannosaurids - this early proto-tyrannosaur
skeleton from the Isle of Wight was already 55 million years old when its
later, larger, and very famous descendant was alive and stalking the continents
of North America and Asia in the very late Cretaceous.
- Baryonychid: (meaning “heavy claw”). In
1996 dinosaur teeth were found on the island that closely resembled those of Baryonyx walkeri, a dinosaur found in
Surrey in1986. This was a 30-foot-long, ten-foot-tall, 2-ton, fish-eating saurischian
dinosaur from southern England with a long, low, crocodile-shaped head.
- Brachiosaurus:
(meaning “arm lizard”). Although the very largest dinosaurs, the herbivourous
sauropods (with very long necks and tails), are quite rare on the Island the
partial skeleton of a Brachiosaurus was discovered in 1992. Although this find
is “only” about 35% complete, a full-length one would be in the region of 82
foot long, 52 foot high and would have weighed about 50 tons!
- Polacanthus foxi: (meaning “Fox’s dinosaur with
many spines”). This was an ornithischian quadrupedal armoured herbivore 13 feet
long with spines that protected it’s neck, flanks, legs
and tail. The
first Polacanthus was found in the 1870s and named in the 1880s after William
Fox, the discoverer, and good a partial skeleton was found more recently, in
the late 1980’s.
- Neovenator salerii: (meaning “Salero's new hunter") is a 26 foot-long carnivorous theropod with ferociously sharp teeth and claws similar to but smaller than an Allosaurus. The first bones were discovered in 1978 and the rest were collected mostly on controlled excavations as and when the cliffs exposed more of the right area, finally yielding a 70% complete skeleton. The bones are excellently well preserved, and were found with other dinosaur and crocodile remains. It was described and named in 1996 and was the first British dinosaur new to science to be discovered since 1983.
-
Valdosaurus: (meaning “lizard of the Wealden”). This rare
Dryosauridae
fossil was a 12 foot-long long
herbivore, found in the 1970’s and looked
like a large Hypsilophodon
Pterosaurs: Pterosaur fossils are particularly rare due to the fragility of their bones. Some have been found on the island, though they are mostly isolated and fragmented remains. The skull of Ornithodesmus, with a broad beak, like the bill of a duck, was found many decades ago. The teeth are short and interlock, suggesting a diet of fish, and it had a wingspan of around 5 m. A new, un-named pterosaur is currently being worked on by experts on the Island. With a wingspan of around 4 m, it is quite small compared to some others found on the island recently that are the same size as the famous Quetzalcoatlus – with a wingspan of 9 to 11metres!
· Cleaning
and conserving the fossil material
When a fossil specimen (a bone, tooth, plant, dropping, gastrolith etc) is uncovered during the excavation it is first brushed free of loose sediment. Then it can be photographed clearly and notes can be taken whilst it is still in place. If the specimen is fragile and is already broken in many places, as often happens, it will be covered in tissue and have a plaster of paris splint made up around it. Once the plaster has set hard the fossil and it’s rigid supporting jacket can be lifted and moved fully supported to the area where the bones are cleaned, keeping all the broken pieces together in association and preventing it from getting further damaged. Many bones found in the cliffs are broken in several pieces already by natural processes either at the time of burial, or when the cliffs move and slump. Care has to be taken to keep the pieces in their relative positions so they can be glued back together correctly. If the specimen is not broken and appears quite robust, then the bone can be lifted onto a specially made wooden stretcher, on top of the loosely filled sandbags that gently take up its shape. It is then carried carefully off the beach.
People who clean the fossils are called preparators – because they prepare the bones for scientific study by cleaning them carefully and mending the breaks appropriately. It is a skilled and painstaking job and it can take many years – up to a decade or more - for several people to clean a large, mostly complete skeleton, depending on its condition. A preparator must work gently and carefully, first studying where the breaks and weaknesses are in the specimen and then deciding on a strategy for removing any adhering sediment in the most appropriate way. The gentlest way is always best, and soft brushes are the first tools to be used, removing all loose sediment and watching for broken bits of bone. At this stage loose bits of broken fossil can be glued back on temporarily, so that its context is not lost. The glues we use are very specific, well-tested, glues which are known to be stable over great lengths of time, and above all are “reversible”. This is so that any repair can easily be un-done later with a solvent and re-set, if need be, with no damage to the fossil. For this project we used the methacrylate co-polymer “Paraloid B-72” which is used in the conservation departments of most major museums in the UK.
When all the loose material has been removed, there is often hard rock still adhering to the specimen. This can be left in some areas to help support the specimen, especially if it is fragile, but in many areas we will want to see the fossil underneath and we can do this where we are able to remove the rock without making the fossil weaker and more prone to damage. To do this we use of a couple of tools powered by compressed air. Firstly we use an “air-chisel” which has a hard tungsten needle tip which vibrates and can gouge away the rock if need be, but is best used to vibrate individual grains of sediment until they break away, and we slowly remove a few grains at a time under the microscope. For this the specimen must rest on a bag filled with sand to absorb the vibrations, or the specimen itself can be broken, especially if one presses too hard! For gentler cleaning, where less sediment or rock has to be removed, we use a machine called an “airabrasive”. This tool forces a mixture of compressed air and powder through a very fine nozzle, just bigger than a pinhead. The ratio of powder to air is chosen by the preparator, as well as the pressure at which it is issued, to get the right level of abrasive force necessary to gently remove the sediment from the fossil without damaging the specimen. Sometimes just compressed air is enough, but usually some powder is needed to abrade the sediment away. For this project we used the two gentlest powders available: sodium bicarbonate, and glass beads.
By knowing the anatomy of the skeleton being worked on, the preparator should be able to judge where the bone is likely to lie under the surface of the rock. This is necessary, as is much care and patience, so that they do not remove too much rock too quickly, or the underlying specimen can be damaged. However, a lot of rocky matrix can be removed surprisingly quickly and the hidden fossil will begin to emerge and become a recognisable bone. Once this gentle cleaning is finished and the whole specimen is as visible as can be (depending on what sediment needs to be kept as support), then any broken pieces can be reattached correctly with the reversible glues. Particularly badly fragmented specimens can seem like giant three-dimensional jigsaws of an unfamiliar picture, with many pieces missing, and no picture to guide you. It is only after these cleaning processes that the full information potential of a fossil is revealed. As the preparator works and the shape of the bone emerges, fine details also appear such as sutures in the skull, muscle attachment rugosities, predation or scavenging marks (gauges in the bone from sharp, powerful teeth), overgrowth scars where bones have been broken during a traumatic incident in the animal’s life but which it survived, and pathological deformation of bones telling us of the diseases an individual animal suffered from. It is often the small details that ensure the positive identification of the animal as one species or another.
Dinosaurs past and present (two volumes). By Czerkas,
S. J. &and Olson, E. C. 1987.
Eyewitness:
Dinosaur.
By David Norman, Angela C. Milner and Colin Keats (illustrator). Reading level
ages 9-12.
DK Publishing; ISBN: 078945808X.
The
Natural History Museum Book of Dinosaurs. By Tim Gardom,
Angela Milner. British Museum (Natural History).
ASIN: 1566490189
The
Complete T-Rex. By John R. Horner and Don Lessem. Published
by Souvenir Press, 1993. ISBN 0285631624
Walking
With Dinosaurs: A Natural History. By Tim Haines. DK
Publishing. ISBN: 0789451875.
Encyclopedia
of Dinosaurs.
By Kevin Padian (editor) and Philip J. Currie (editor). Published by Academic Press. ISBN: 0122268105.
Beyond the Dinosaurs : Sky Dragons, Sea Monsters, Mega-Mammals, and Other Prehistoric Beasts.
By Howard Zimmerman (Reading
level: Ages 4-8). Published by Atheneum; ISBN: 0689841132.
Dragons of the air: An
account of extinct flying reptiles. By H. G. Seeley. Original published by D. Appleton
& Co, 1901. Reprint, out of print: Dover Publications, 1967.
Vertebrate Palaeontological
Techniques.
Edited by Patrick Leiggi and Peter May. Published by Cambridge University
Press, 1994.
Digging up Bones: the
excavation, treatment and study of human skeletal remains. By D. R. Brothwell.
Published by British Museum (Natural History) 1965 (out of print).
· Details of equipment:
Equipment for cleaning the fossil material:
Angle grinder with a stone cutting wheel and pneumatic engraving pens (Desoutter VP2) for removing thick rock matrix. Airabrasive units utilising compressed air and specific powders (in this case sodium bicarbonate and glass beads) were used for more delicate removal of matrix from around the specimen. A compressor is needed to run the airabrasive, and the work is undertaken in a glovebox with a special dust-removing extract system.
Health & safety equipment:
Disposeable latex gloves,
impact goggles, dust masks, eye wash bottles, first aid kit, and labcoats for
cleaning the bones. Hard boots, goggles, thick gloves and sunblock for the
diggers and other workers at the excavation sites. “Control Of Substances
Hazardous to Health” forms and risk assessments.
Consolidants and glues:
Paraloid B-72 in acetone as
a consolidant, applied with polypropylene pipettes. Paraloid B-72 from tubes as
an adhesive.
Recording kit for
excavations:
Self-sealing polythene bags
with write-on panels, string, raffle tickets, plastic marker pegs, tent pegs, permanent
marker pens, pencils, thick gloves, hardback notebook, context sheets,
clipboard, first aid-kit.
Email: enquiries@fieldworklogistics.com
Click here to
return to the top of the page