Lower Upnor’s London Clay shore is a modest collecting locality beside the Medway, reached by the seawall near the yacht club. Slumped, vegetated cliffs and modern shore deposits often hide the clay, and finds can be scarce. Patient examination of loose upper-foreshore shingle and nodules may reveal marine fossils, provided you stay well clear of deep estuarine mud.
FIND FREQUENCY: ♦ – Usually low yield: occasional nodules and fossil fragments reward careful searching, but an empty-handed visit is possible.
CHILDREN: ♦♦♦ – Older children need close supervision around soft mud and sharp rubbish; avoid the lower shore.
ACCESS: ♦♦♦ – The village-end car park leads to the seawall approach beside the yacht club. Firm upper-shore access depends on local conditions.
TYPE: – Low, discontinuous London Clay cliffs, historically extending about 300 m, and an estuarine beach with shingle and modern silt.
DIRECTIONS
♦ From M2 Junction 1 take the A289 towards Wainscott. Continue via Four Elms Roundabout towards Rochester, then follow the route towards the Medway Tunnel and the signed Lower Upnor turning.
♦ Follow the signs into Lower Upnor and continue towards the village-end car park before the yacht club. Observe the current junction layout and road signs rather than attempting an informal turn across traffic.
♦ Medway Council lists Lower Upnor car park at Albion Place, ME2 4XB, as free, with 57 spaces and a 20-hour maximum stay followed by no return within 2 hours. Check the signs when you arrive; this postcode is for parking.
♦ Walk eastwards along the seawall beside the yacht club to the shore. Remain on firm upper-ground routes and return before the tide or mud makes access unsafe.
FOSSIL HUNTING
Lower Upnor is a modest London Clay collecting shore, where a careful search may produce only a few finds. The original field account records occasional shark teeth and phosphatic nodules in upper-foreshore shingle and naturally released material near the small cliffs. Concentrate on visible, safely reachable loose pieces on firm ground. Much of the clay is obscured by vegetation, slumping or modern shore deposits, so the lack of a clear exposure is normal and is not a reason to dig into a slope.
For small teeth, scan a limited patch of shingle closely rather than walking quickly over a large area. A recognisable tooth combines a crown with a root or broken root base; a pointed black stone alone is not enough. Look at both faces and the edges with a hand lens, retaining any root fragments. Worn or broken fragments may remain unidentified even when they are recognisably teeth.
Nodules require a different search image. Look for a small piece of shell, a regularly curved outline or an ornamented surface showing through the matrix. A rounded nodule can be completely barren, while an unpromising-looking fragment may preserve part of a fossil. Turn a loose piece to examine its existing surfaces, but avoid splitting it simply to discover whether it contains something. A crustacean may continue into the rock beyond the exposed fragment, and a hammer blow can destroy the features needed for identification.
Local records include the lobster Hoploparia gammaroides and the crabs Portunites incertus and Zanthopsis leachii, alongside bivalves, gastropods and trace fossils. Claw fragments and pieces of body covering can be worth recording even when incomplete; a species identification requires more than resemblance to a published photograph. For shells, retain the part that shows the hinge, coiling or surface ornament instead of trimming the specimen down to its outline.
Keep promising pieces with their matrix, label the precise stretch of shore and photograph the find before preparation. Note whether it was loose in shingle or already naturally exposed in clay: a beach position cannot by itself establish the original bed. Modern rubbish can be mixed with the fossils, so leave sharp or suspicious debris alone and do not cross soft mud to reach a distant nodule.
The nearby Lower Upnor Sand Pit is a separate geological exposure, famous for an older Palaeogene succession. Its rich fossil records are not a checklist for this London Clay beach. Enjoy the shore for the occasional small find it actually offers, without expecting the quarry’s fauna or treating the shared locality name as proof of age.
GEOLOGY
The collecting shore at Lower Upnor exposes early Eocene London Clay, a fine-grained marine deposit belonging to the Thames Group. Its low cliff and occasional foreshore patches give a very different view from a clean quarry face: slumping, vegetation and modern estuarine mud repeatedly interrupt the bedrock. Fresh London Clay is blue-grey and becomes brown on weathering, so differently coloured patches need not represent different formations.
The original field account places this shore in informal Division B1, within the Aveley Member. That member is regionally characterised by silty clay, discontinuous claystone concretions and some finer sandy or micaceous partings. The B1 attribution is useful locality context, but the small, broken exposures do not provide a complete member thickness or a continuous bed-by-bed log. In particular, the nearby Lower Upnor Sand Pit exposes a different, older Thanet–Lambeth–Harwich succession; its famous units and fossils cannot be transferred to this London Clay shore.
Natural weathering and slumping free harder material from the soft clay. Phosphatic nodules occur among the upper-shore shingle, and the historical fauna includes lobster and crab remains, molluscs and trace fossils, with occasional shark teeth reported. A nodule may retain fossil material beneath an inconspicuous outer surface even after the original clay around it has disappeared.
Tides subsequently move the released nodules and other debris, while fresh silt can bury the platform again. This explains why fossils may occur in a loose shore concentration although little bedrock is visible nearby. It also limits interpretation: a loose fossil can be consistent with the local London Clay fauna without preserving the precise bed or height from which it came.
Detailed geology and stratigraphy of Lower Upnor.
THAMES GROUP
The early Eocene marine deposits belong to the Thames Group. The units described here are the beds represented at this collecting locality; the complete regional group is not exposed on this shore.
London Clay Formation
Fine marine sediment forms blue-grey clay when fresh and brown clay where weathered. Carbonate concretions, phosphatic nodules and pyrite occur within the clay, but they are different materials: a loose nodule is not itself a formal bed and does not establish the exact horizon of a beach find.
Aveley Member
The B divisions of the London Clay lie within the Aveley Member in the current BGS framework. Its regional character is mainly silty clay with discontinuous claystone concretions; some levels contain finer sandy or micaceous partings. B1 and B2 are informal subdivisions within this framework, rather than formal members. No complete member thickness is implied for this foreshore.
Division B1 shore exposure
The 2012 guide assigns the small foreshore and low-cliff exposure to B1. Weathered clay is commonly hidden by slumping and vegetation; phosphatic nodules occur among the upper-shore shingle. The detailed Thanet–Lambeth–Harwich sequence of Lower Upnor Sand Pit belongs to a different exposure and is not the succession seen on this collecting shore.
Modern mud, shingle and disturbed cliff debris
Modern estuarine silt and beach debris cover much of the clay. A nodule picked from shingle has already moved from its original bed, so its exact height in B1 is normally unknown. The presence of a modern shore cover is not a new bed within the London Clay.
References
BGS Lexicon: London Clay Formation
BGS Lexicon: Aveley Member
Aldiss 2014, Palaeogene stratigraphical framework, OR/14/008
UK Fossils, Lower Upnor (field inspection 2012)
SAFETY
Deep estuarine mud becomes more hazardous towards low water. Stay on firm upper-shore ground, avoid channels and allow time to return before incoming water affects the route.
Sharp rubbish, hidden glass or metal and unstable slipped material are additional hazards. Avoid kneeling where debris may be concealed and do not enter or dig beneath unstable banks.
EQUIPMENT
Bring a hand lens, sturdy footwear, protective gloves, padded containers, tide information and a phone. Inspect the ground before using knee pads; no digging tools are needed for routine loose collecting.
CLEANING AND TREATING
Keep phosphatic nodules whole in the field and wrap them individually. Exposed limbs or bones may continue beneath apparently blank matrix. Begin with a soft brush and stop if the fossil or its matrix moves with the dirt. Hard nodules can require fine mechanical preparation under magnification by an experienced preparator.
Avoid household acids, bleach and routine varnishing. Pyritic specimens need appropriate cleaning followed by dry, stable storage and regular checks for powdering, cracking or acidic decay. Do not seal wet material into long-term storage. Keep potentially important finds unprepared until a specialist has examined them.
IDENTIFY YOUR FINDS
Need help identifying a fossil? Share clear photos, where you found it and its size with the community.
FURTHER READING
Deposits: Seeds from the London Clay (regional background)
Deposits: Crystals and minerals of the London Clay (regional background)
BGS Lexicon: London Clay Formation
BGS Lexicon: Aveley Member
Natural England: Tower Hill to Cockham Wood SSSI citation
ACCESS RIGHTS
Tower Hill to Cockham Wood SSSI protects adjacent woodland and the Upnor Quarry area. Use established public paths and respect signs and property boundaries. The quarry and this collecting shore are distinct localities.
Path access is not permission to excavate private ground, cliff faces or a protected quarry. Confine a casual visit to small loose material where access is permitted, and obtain the appropriate agreement for intrusive work.
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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