Introduction
Hastings is a large town (and borough) on the coast of East
Sussex in Southern England with a population of over 86,000 people.
Immediately east of the town and extending for four miles towards
Fairlight are a series of spectacular golden coloured cliffs
that tower over 100 metres above sea-level.
In recent centuries
many fine fossils have been exposed within
the cliffs and foreshore, including the skeletal remains of dinosaurs,
pterosaurs and fish, and other creatures and
vegetation that inhabited this environment around 140 million
years ago (mya).
The sandstone rocks and fossils provide evidence of a large lake
or lagoon, rich in aquatic and land based life, including
several species of herbivorous (plant eating) and carnivorous
(meat eating) dinosaurs. Although dinosaur bones are relatively
rare the evidence of these reptiles movements can be found more commonly in
the form of footprints and casts on the surface of
fallen rocks.


Left: Parking is
available east of the town along Rock-a-Nore Road. Right:
View from the car park area overlooking the cliffs east of Hastings.
Access to the cliffs and foreshore is made from Rock-a-Nore road,
along which 'pay and display' parking is available throughout the
year (see above-left). A visit to Hastings is best timed to coincide
with a falling tide as much of the foreshore is otherwise submerged
beneath the sea, however depending on the height of the high-tide
some areas of the backshore may remain accessible.
The geology of Hastings
The sediments exposed in the cliffs and on the foreshore
between Hastings and
Fairlight in the east date from the Early Cretaceous epoch (Berriasian -
Valanginian stages) approximately 143-139 mya.
The sand and silt was transported to the area by rivers and streams,
and then settled in a large lake/lagoon (predominantly above sea
level). At this time Hastings and the rest of Britain were part of the
European landmass, located around 40°north of the equator, on the same
latitude as the Mediterranean Sea is today.
For much of the Berriasian and Valanginian stages the climate
was sub-tropical with seasonal changes in temperature and rainfall.
The mostly low-lying land that surrounded the water was home to a rich plant flora,
revealed by the abundance of fossilised plant material found
throughout the succession. Conifers and related plants were the
dominant tree and cycad-like plants were also present (see
below-left). Grasses did
not exist during the Cretaceous, instead the ground was covered by
the horsetail Equisetites.


Left: A conifer
cone reveals the presence of neighbouring vegetation. Right:
Rippled sandstone reveals a sediment formed in shallow water.
Hastings is part of the Weald Basin, an area of uplifted land
that occupies over 4,000 square kilometres of South East England (south
of London), between the South and North Downs.
The uplift is the result of pressure generated by the European and
African continental plates colliding (generating the Alps), a process that took place to
the greatest extent 30-25 mya (see Fig.1 and 2 below).


Figure 1: A geological summary of South East England
showing the location of the cross-section. Figure 2: A
cross-section through the Weald. Not to scale.
Over time the surface of the uplifted land has been
greatly eroded, stripping away the upper (later) layers and exposing the underlying (earlier) sediments.
Erosion has occurred at its greatest towards the centre of
the anticline where the uplift is at its highest. The process of erosion is the reason why the top of the cliffs at
Hastings are not capped by several hundred metres of clays and Chalk in
particular.
The sediments exposed between Hastings and
Fairlight belong to the Ashdown and Wadhurst Clay
formations, and are comprised mostly of alternating layers of
sandstones, siltstones and mudstones. Fig. 3 below provides a summary of
the geology between East Hill and Ecclesbourne Glen, including the
surface position of the Foul Ness Fault.

Figure 3: The
stratigraphy of the cliffs east of Hastings towards Ecclesbourne Glen
and beyond.
Travelling north-east from Hastings the upper sandstone division of the Ashdown
Formation is well exposed in the cliff and on the foreshore. This
division, known as the Ashdown Sandstone, measures between 30-50m
thick and was originally deposited around 142 mya. The course sandstone
(more arenaceous) is thought to reflect a period of high rainfall
during which large volumes of sand were eroded from the source rocks
and transported into the area.
The Ashdown Formation also encompasses the underlying Fairlight Clay
division, a less sandy (more argillaceous) sediment comprised mostly of siltstone and
mudstone, dating from c.143 mya. The reduced volume of sandy
sediments within the Fairlight Clay is though to reflect a period of
reduced rainfall during which erosion of the source rocks was less. The
uppermost beds of the Fairlight Clay can be seen in the lower cliff and
on the foreshore a short distance beyond the Foul Ness Fault (see Fig.3). Together the two divisions of the Ashdown Formation measure approximately
120m.
Overlying the Ashdown Formation is the Wadhurst Clay Formation,
which includes the Cliff End Sandstone at its base; between Hastings and
Fairlight approximately 20m of the Wadhurst Clay is exposed. These
sediments date from around 139 million years ago and are the earliest
exposed in situ along this stretch of coast. The Wadhurst Clay is
comprised mostly of grey mudstone with subordinate sandstone and
siltstone beds (among others), and represents the marginal area of a
lagoon, into which influxes of salt water occurred during a
transgression phase.
Travelling east from Hastings the
underlying sediments are generally brought to the surface by localised
folding, however at the eastern end of Fairlight Cove (approximately 4
miles from Hastings) Haddock's Reverse Fault brings the overlying
Wadhurst Clay Formation to within several meters of the beach level. See
the
Fairlight page for more information.
Where to look for fossils?
Fossils can be found throughout the fallen rocks and in situ on the
foreshore, especially following periods of stormy weather. Although
fossils are common, in particular the bivalve Neomiodon, other fossils are less so
and it may require several visits to develop a thorough understanding of
this prehistoric environment.
The best place to explore for dinosaur bones and footprint/casts
is among the boulders on the foreshore and towards (not
directly beneath) the base of the cliff. The cliffs at Hastings are
unstable and falling rocks occur frequently throughout
the year; it's always a good idea to keep well clear of the area
immediately beneath the cliff face. In recent years a number of large collapses have created vast accumulations of boulders on the beach,
and it's from these that dinosaur footprints can occasionally be found.
Dinosaur footprints and casts are distinguishable from the
surrounding rock by their characteristic three-toed shape.
Footprints appear as impressions (indented) on the surface, whereas
casts usually protrude above the surrounding rock. For every
footprint is a cast, although due to the chaotic nature of cliff
collapses they are seldom found in close proximity.
The footprints were originally formed in moist but relatively firm
sediment, near to the water's edge (see Fig. 4 below). Immediately
following their formation the sediment dried and hardened in the sun.
Soon after, perhaps following a flash-flood, the footprints were buried
by additional sediment of a slightly different composite derived from
upstream. These subtle differences in composite would later encourage
the separation of the rock between the two layers.


Figure 4: A reconstruction showing
a sun-baked dinosaur trackway at the edge of a drained lake.
Figure 5: An illustration of a dinosaur footprint and
cast.
After millions of years the sediment lithified (turned to rock)
and natural weaknesses formed along the horizon between the two original
layers.
Following exposure in the present day large sections of the cliff collapse onto the beach. As this
occurs the two original
layers separate along the natural weakness leaving an indented footprint
on one surface and a protruding cast on the other (see Fig. 5 above).
In some instances the weakness passes through the cast
instead of around it, in which case the two layers may sheer the fossil
in half, creating a cross-section on both surfaces. In other
instances the cast may become separated from the rock and
appear as an isolated boulder.
Below are two examples of the most common dinosaur
footprints/casts at Hastings. The first (and largest in this
instance) is a cast
formed by an adult Iguanodon, a herbivorous dinosaur
that could reach up to 10m (33ft) from head to tail. Iguanodon
featured a narrow head with a strong beak and grinding teeth
suitable for grazing on vegetation growing near the lakeside and
river banks. It predominantly walked on all four legs, although the
larger muscular hind pair carried the greatest load; the lighter
front pair featured an additional spike on the first finger used for
gathering food and to defend itself. The cast below shows Iguanodon's
characteristic short, wide
toes, ideally suited for carrying the dinosaur's heavy body and
tail.


Left: Bill explains to
Louis how the Iguanodon foot cast was formed.
Right: A large Iguanodon foot cast partly protruding
from a boulder on the foreshore.
The second footprint shown below belongs to a fast moving
carnivorous theropod dinosaur. Unlike Iguanodon, theropod toes
were long and pointed with a
sharp claw used for improved mobility and clasping prey. The generic
features make a precise identification impossible, however for the
purposes of this page the footprints are attributed to Baryonyx.


Left: Discovering
Fossils event participants move the shingle away to reveal two theropod
foot prints. Right: A large theropod footprint
cross-section.
In adulthood Baryonyx was a formidable predator, standing on
two powerful rear legs and measuring up to 10m (33ft) from head to
tail. These dinosaurs featured a relatively narrow head with long jaws
equipped with an arsenal of teeth (similar to a crocodile)
ideal for predating upon fish and possibly Iguanodon too.
Baryonyx was also equipped with a large claw at the end of
each forelimb, most probably used to prevent prey from escaping.
There are usually several footprints to be found at any one time,
however for much of the year they may be buried beneath shingle and
difficult to locate without prior knowledge of the area. As always,
patience and persistence are the key to success.
As with all coastal locations, a fossil hunting trip is best timed to coincide
with a falling or low-tide. For a relatively low one-off cost we
recommend the use of Neptune Tides software, which provides
future tidal information around the UK. To download a free trial
click here.
Alternatively a free short range forecast covering the next 7 days
is available on the BBC website
click here.
What fossils might you find?
Below are a selection of some of the fossils you may encounter
during a visit to Hastings. These specimens were observed or collected during several
visits and are not representative of the volume observed during a
typical day.


Left: An Iguanodon foot
cast measuring 45cm across, found among the foreshore boulders.
Right: An Iguanodon vertebra on display during a
Discovering Fossils event at Hastings, found by Gordon Elder on the foreshore.


Left: The stem impression of a horsetail (Equisetites).
Right: A close-up reveals the individual segments of the stem.


Left: A thin, crushed
piece of fossilised wood (lignite).
Right: A slice of sandstone with characteristic ripples
and bivalve feeding burrows/pellets.


Left: A sandstone slab
preserving the narrow water channels, known as gutters, that formed as
flood water drained away.
Right: A close-up reveals bivalves.


Left: A gutter cast
lined with a large number of bivalves (Neomiodon).
Right: A close-up.


Left: A thin slice of
sandstone with bivalve feeding burrows/pellets.
Right: A slab of sandstone packed with bivalves
(Neomiodon).


Left: A concentration
of fish scales, teeth and bones.
Right: A Close-up.




Left: The scale
impressions of a large fish (Lepidotes). Right: Small fish bones and a shiny
circular black tooth belonging to
Lepidotes.
Tools & equipment


Left: Walking boots
are recommended as the terrain is rocky and slippery. Right:
A well equipped group listen to a guidance from Robert.
It's a good idea to spend some time considering the tools and
equipment you're likely to require while fossil hunting at
Hastings. Preparation in advance will help ensure your visit is
productive and safe. Below are some of the items you should consider
carrying with you. You can purchase a selection of geological tools
and equipment online from
UKGE.
Hammer:
A strong hammer will be required to split prospective rocks. The
hammer should be as heavy as can be easily managed without causing
strain to the user. For individuals with less physical strength and
children (in particular) we recommend a head weight no more than
500g.
Chisel: A chisel is required in conjunction with a
hammer for removing fossils from the rock. In most instances a
large chisel should be used for completing the bulk of the work,
while a smaller, more precise chisel should be used for finer work.
A chisel founded from cold steel is recommended as this metal is
especially engineered for hard materials.
Safety glasses: While
hammering rocks there's a risk of injury from rock splinters
unless the necessary eye protection is worn. Safety glasses ensure any splinters are deflected away from the eyes. Eye
protection should also be worn by spectators as splinters can
travel several metres from their origin.
Strong bag: When considering the type of bag to use it's worth setting aside
one that will only be used for fossil hunting, rocks are usually
dusty or muddy and will
make a mess of anything they come in contact with. The bag will also
need to carry a range of accessories which need to
be easily accessible. Among the features recommended include: brightly coloured,
a strong holder construction, back
support, strong straps, plenty of easily accessible pockets and a rain cover.
Walking boots: A good pair of walking boots will
protect you from ankle sprains, provide more grip on
slippery surfaces and keep you dry in wet conditions. During your
fossil hunt you're likely to encounter a variety of terrains so
footwear needs to be designed for a range of conditions.
For more information and examples of tools and equipments
recommended for fossil hunting
click here
or shop online at
UKGE.
Protecting your finds
It's important to spend some time considering the best way to
protect your finds onsite, in transit, on display and in storage.
Prior to your visit, consider the equipment and accessories you're
likely to need, as these will differ depending on the type of rock,
terrain and prevailing weather conditions.


Left: Fossil
wrapped in foam, ready for transport. Right:
A small compartment box containing cotton wool is ideal for
separating delicate specimens.
When you discover a fossil, examine the surrounding matrix (rock)
and consider how best to remove the specimen without breaking it;
patience and consideration are key. The aim of extraction is to
remove the specimen with some of the matrix attached, as this will
provide added protection during transit and future handling;
sometimes breaks are unavoidable, but with care you should be able
to extract most specimens intact. In the event of breakage,
carefully gather all the pieces together, as in most cases repairs
can be made at a later time...continued.

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