Bridlington’s North Beach becomes increasingly rocky towards Sewerby, where fossil-bearing Chalk blocks occur among the shingle. Sponges, shells and echinoids are the main attractions, while glacially transported material adds a different part of the area’s geological story.
FIND FREQUENCY: ♦♦♦♦ – Productive Chalk fossils occur in suitable loose blocks, but beach cover and recent falls make results variable.
CHILDREN: ♦♦♦♦♦ – The main beach can suit supervised families in calm conditions; the cliff foot and distant tidal shore are unsuitable play areas.
ACCESS: ♦♦♦♦ – Use the maintained North Beach frontage. The walk towards Sewerby becomes stonier and more tide-dependent.
TYPE: – Loose fossil-bearing Chalk blocks and pebbles; in-situ cliff and foreshore geology can be observed without excavation.
DIRECTIONS
♦ Head for Bridlington’s North Beach and the maintained seafront access points. Follow the shore towards Sewerby only when the tide and weather allow a safe return.
♦ The council lists Limekiln Lane Car Park, YO15 2LX for the northern end of the resort. It is a charged, summer-only car park; check opening arrangements before relying on it.
♦ Use open steps or ramps from the promenade. Do not scramble down the cliff or assume that a route shown in an older guide remains usable.
♦ This guide concentrates on the North Beach–Sewerby shore. The historical Bridlington Crag is not a reason to dig into South Beach dunes or sea defences.
♦ Ref: TA 19803 68580
FOSSIL HUNTING
The best approach is to examine loose Chalk blocks and smaller pebbles on the increasingly rocky shore towards Sewerby. Sponges are conspicuous finds, but shells, echinoids and detached echinoderm plates also occur. White colour alone is not diagnostic: the beach includes modern bored Chalk and transported stones as well as fossil-bearing blocks.
The local bedrock source is the upper Flamborough Chalk succession. Much beach material has moved from its original position, so a fossil found on North Beach cannot automatically be assigned to a named marl or sponge bed. Record the precise findspot, matrix and whether the specimen was loose.
Bridlington also has a separate history of Pleistocene marine shells in glacial deposits, the Bridlington Crag. These shelly sands and clays occur as displaced inclusions, not a continuous Chalk bed. Their rare exposure should be documented rather than pursued by digging into dunes, cliffs or coastal structures.
Significant fossil discoveries and geological research at Bridlington.
1826–1835 – Early records of Bridlington Crag
The shelly deposit was mentioned by Adam Sedgwick in 1826 and described by William Bean in 1835. Its unusual mixture of marine fossils made Bridlington important in the developing study of glacial sediments.
1878 – Lamplugh explains the transported shelly deposits
George William Lamplugh published his first study of marine shells in the Bridlington boulder clay. He interpreted the Crag as shelly material incorporated into glacial till, rather than a continuous bed in its original position.
About 1884 – The buried cliff at Sewerby is recognised
Clement Reid recognised the old cliff at the northern end of the Bridlington shore after Lamplugh had identified a nearby bone-bearing deposit. Subsequent excavation clarified its relationship to the younger cover.
1993 – The upper Chalk succession is formalised
Felix Whitham’s measured coastal framework distinguished the Sewerby Member and its marl and sponge-rich horizons, improving correlation of the Chalk source beds north of Bridlington.
2018–2019 – Shelly till is exposed on North Sands
Temporary exposures on Bridlington North Sands revealed Basement Till with marine shells and shell fragments. Their recording renewed opportunities to investigate a deposit whose age and correlation remain debated.
GEOLOGY
The North Beach–Sewerby shore lies at the transition from the soft deposits of Holderness to the Chalk cliffs of Flamborough Head. The exposed Chalk towards Sewerby belongs to the upper part of the Flamborough Chalk Formation, especially the Sewerby Member, within the White Chalk Subgroup and Chalk Group.
The Chalk represents Late Cretaceous marine sediment, with sponge-rich intervals, shell debris and thin marl markers. The beds at the Sewerby end are among the youngest Chalk exposed on this coast, not older equivalents of the Danes Dyke succession. The full formation thickness measured regionally must not be confused with the low cliffs visible here.
Pleistocene deposits overlie and locally conceal the bedrock. At the northern end, the Sewerby buried cliff records an older coastline; around Bridlington, glacial till can contain transported marine shell-bearing sediment. The modern beach mixes material from these different sources, so its pebbles do not form an orderly geological section.
The local Chalk succession and younger deposits at Bridlington.
This account follows the local coastal source succession, with younger superficial deposits described separately. Thicknesses below refer to published marker measurements, not to an uninterrupted section visible at every visit.
CHALK GROUP
WHITE CHALK SUBGROUP
Flamborough Chalk Formation
The formation is predominantly flintless marine Chalk with marl seams. Here the important distinction is between the crinoid-bearing Danes Dyke succession and the younger Sewerby Chalk; the full formation and all of its members are not simultaneously exposed at one access point.
Sewerby Member
This is the upper part of the coastal Flamborough Chalk succession. Its basal beds retain late Santonian Marsupites; younger beds westwards contain the early Campanian sponge-rich succession. Loose beach specimens need not come from the nearest visible bed. The member’s full coastal thickness is not the height of the local cliff.
Flamborough Sponge Bed
The principal sponge-rich interval is about 11 m thick in the published coastal log. It begins roughly 2 m above the Daneswood Upper Marl and continues to about 5 m above the Longwood Marl. Sponges are distributed through a substantial thickness of Chalk, rather than confined to a single paper-thin layer.
Longwood Marl
A grey marl about 60 mm thick, containing silt and compacted clay, lies within the upper part of the principal sponge-rich interval. It is a marker within that interval, not the top of all sponge-bearing Chalk.
Marton Hall Marl
This sharp-based, silty grey marl is about 40 mm thick in the measured coast succession towards Sewerby. It lies above the principal sponge-rich interval.
Upper unnamed sponge bed
A second conspicuous sponge-rich bed, about 1 m thick, occurs between the Marton Hall and Sewerby Hall marls. It is distinct from the much thicker principal Flamborough Sponge Bed below.
Sewerby Hall Marl
The seam is around 40–50 mm thick and consists of pale grey marl and compressed Chalk; locally it becomes a more uniformly chalky marl.
Sewerby Steps Marl
A brown, clay-rich marl with a sharp base, approximately 60 mm thick, marks the highest part of the coastal source section near Sewerby Steps. Its name does not imply that the bed is exposed on Bridlington’s sandy town beach.
Offaster pilula horizon
A discrete occurrence of this small echinoid is recorded above the sponge-rich beds in the Sewerby coastal succession. It is a useful biostratigraphical horizon, not a separate formation or a guaranteed loose-beach find.
Scaphites binodosus horizon
The highest Chalk at Sewerby Steps has yielded this heteromorph ammonite, called Discoscaphites binodosus in older accounts. The occurrence characterises the upper coastal interval; it should not be used to assign every ammonite found on Bridlington beach to that bed.
Bridlington Crag and Basement Till
The shelly sands and clays known as Bridlington Crag occur as irregular glacially transported inclusions in till. Their marine fossils pre-date the transport event. The age and correlation of the Basement Till remain debated, and an old fixed age should not be treated as settled.
Sewerby buried-cliff deposits: a separate northern-end section
The interglacial shoreline is preserved where the modern coast cuts an older Chalk cliff. It is not a continuous layer beneath the whole resort beach.
Interglacial beach gravel
The Ipswichian beach is up to 1.5 m thick in the published section: rounded Chalk pebbles, other stones, marine shells and mammalian remains. It is distinct from transported Bridlington Crag.
Rainwash
Clay-rich slope-washed Chalk sediment, up to 1.5 m thick in the published section, overlies the old beach and banks against the buried cliff foot.
Blown sand
A former dune-sand wedge rests above the rainwash and thickens to 8 m against the buried cliff in the published section.
Chalk rubble
Angular Chalk debris with fine sediment records cold-climate slope deposition. It drapes the former cliff top at less than 0.3 m thick and reaches 6 m beyond the old cliff line in the published section.
CALEDONIA GLACIGENIC GROUP
NORTH SEA COAST GLACIGENIC SUBGROUP
Holderness Formation
Skipsea Till Member
The younger till is a mainly grey-brown, matrix-supported mixture, locally streaked with Chalk, sandstone or shale. Sand and gravel lenses can be folded or attenuated within it. It overlies the buried-cliff deposits; transported stones must be distinguished from the underlying marine fossils.
Sewerby Gravels
Gravel above the till completes the classic local section. Its depositional interpretation has been debated; it is not assigned an unsupported new formal member here.
Modern North Beach
Sand, shingle and loose blocks are continually redistributed by waves. Any temporary till or shelly exposure should be recorded with a date and precise position, because burial and erosion can remove it quickly.
References
Whitham (1993): coastal member and marker descriptions, summarised by BGS
BGS: individual Chalk marker horizons
Geological Conservation Review: Flamborough Head
Local geological excursion: Chalk of Flamborough Head
Geological Conservation Review: Sewerby buried cliff
Penny (1964): Lamplugh’s research on Bridlington Crag
Connell and colleagues (2021): renewed North Sands till exposures
SAFETY
Check tides and weather before setting out. Visit the rocky shore on a suitable falling tide and allow enough time to return before the route narrows; onshore winds and waves can make conditions worse than tide tables alone suggest.
Keep well away from the Chalk cliff base, overhangs and fresh falls. Blocks can fall without warning, while wet Chalk, algae and loose boulders are slippery. Do not shelter under cliffs or climb onto large unstable fallen blocks.
A short resort-beach visit is different from a longer walk under the Sewerby cliffs. Turn back rather than pressing on around a tidal obstruction or using an eroding slope as an escape route.
Carry a charged phone and tell someone your plan. In an emergency call 999 or 112 and ask for the Coastguard.
EQUIPMENT
Sturdy footwear, tide information, a hand lens, a camera, labels, soft wrapping and rigid specimen boxes are more useful than a heavy toolkit for a first visit.
A hammer is not essential for finding loose fossils. Avoid the cliff and attached foreshore; if work on a loose block is permitted, use eye protection and keep everyone else well clear. Leave difficult or scientifically important finds for specialist assessment.
CLEANING AND TREATING
Wrap Chalk fossils separately, keeping any loose plates with their specimen. Crinoid cups, sponges and echinoid tests can break at weak surfaces, so retain a supporting block rather than trying to remove every trace of matrix on the beach.
Dry damp finds slowly, then use a soft brush and careful work under magnification. Do not soak crumbly marl, fragile shells or iron-stained specimens indiscriminately. Chalk and many fossil shells are carbonate: household acids will damage both. Avoid bleach, wire brushes and routine varnish.
For hard Chalk, mechanical preparation is slow and delicate; stop when fossil and matrix break together. Seek experienced advice before treating unstable pyrite or marcasite, or attempting to expose a complete crinoid or starfish. Potentially significant specimens should be documented and left unprepared for specialist assessment.
IDENTIFY YOUR FINDS
Need help identifying a fossil? Share clear photos, where you found it and its size with the community.
FURTHER READING
Deposits: a fossil hunter’s guide to the Yorkshire coast (regional background)
BGS field guide: Chalk of Flamborough Head
Geological Conservation Review: Flamborough Head Chalk
BGS: Sewerby Member
Early collectors and significant Chalk specimens
Geological Conservation Review: Sewerby buried cliff
Lamplugh and the Bridlington Crag
ACCESS RIGHTS
The Chalk cliff and foreshore at the Sewerby end form part of the Flamborough Head Site of Special Scientific Interest (SSSI). This does not mean that every part of Bridlington’s resort beach has identical designation or ownership.
Follow current signs, barriers and reserve instructions. Observe the rock sequence without cutting the cliff or damaging the foreshore, keep collecting to modest loose material where permitted, and seek the landowner or site manager’s advice if a find would require excavation.
Public beach access is not permission to excavate dunes, cliffs, buried archaeological deposits or sea defences. Photograph and report unusual in-situ discoveries rather than attempting unauthorised removal.
The Flamborough Head No Take Zone extends between Sewerby Steps and Danes Dyke and 700 m seawards. Do not remove living marine animals or plants, or stones carrying them. Follow the current local conservation guidance before collecting within this zone.
It is important to follow our ‘Code of Conduct’ when collecting fossils or visiting any site. Please also read our ‘Terms and Conditions’.
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