The Pettycur Bay shore at Kinghorn reveals a Carboniferous volcanic landscape with an exceptional record of fossil plants. Basaltic lavas, ash-rich rocks and plant-bearing limestone preserve evidence of vegetation caught up in volcanic activity. The best-known plants were identified from carefully prepared scientific specimens, making this a rewarding place to observe geology rather than expect obvious fossils in every rock.
FIND FREQUENCY: Fossil plants are scientifically important but often difficult to recognise without specialist preparation.
CHILDREN: The sandy bay is more suitable than the slippery rock platforms; supervise children closely beside water and cliffs.
ACCESS: Approach from Pettycur harbour and assess the tide before walking west across the bay.
TYPE: Volcanic foreshore and low cliffs, with historically documented plant-bearing deposits.
DIRECTIONS
♦ Head for Pettycur harbour on the southern side of Kinghorn. This guide follows Pettycur Bay, rather than the separate Abden shore north-east of the town.
♦ The original approach begins by the harbour, where the old guide records a parking area overlooking the bay. Follow current parking signs and keep harbour access clear.
♦ When the tide permits, walk west across the bay towards the rocky foreshore and low cliff exposures. Stay on the accessible shore and turn back before the returning tide restricts the route.
♦ Original shore reference: 56.06246°N, 3.18106°W. This is an orientation point, not a surveyed fossil bed or a guaranteed safe access route.
FOSSIL HUNTING
Begin by looking at the rock itself. The shore is dominated by volcanic material, whereas the famous Pettycur fossils occur in particular plant-bearing limestone and ash-rich deposits associated with the lavas. A pale patch or rounded structure in basalt is not automatically a fossil: mineral-filled cavities, veins and weathering can produce misleading patterns. Compare several naturally exposed surfaces and photograph possible organic structures close up, with a scale and a wider view showing their setting.
Pettycur is especially important for anatomically preserved plants. Mineralisation retained internal tissues of stems, leaves, rooting structures and reproductive organs, rather than simply pressing a leafy outline into a bedding plane. Much of the scientific record comes from thin sections and successive peels of museum specimens. On an untouched weathered surface, a plant fragment may show only as a small irregular or circular patch; its internal anatomy and identity may be impossible to determine with a hand lens. Photograph promising material without scratching or testing it with a hammer.
The historically described flora includes lycopsid stems such as Paralycopodites brevifolius and Lepidophloios scottii, fern material including Botryopteris antiqua and Stauropteris burntislandica, and the unusual reproductive structure Cheirostrobus pettycurensis. These names describe specialist anatomical records, not a checklist of readily collectable beach specimens. Different organs of one plant can carry different fossil names, so a long species list does not equal the same number of complete plants.
Preservation also varies between deposits. The classic peat-like limestone contains densely associated plant tissues, while other material contains more volcanic ash and charcoal. Fern-rich and lycopsid-rich assemblages occur, and some separate mudstones have yielded flattened plant remains. Loose blocks on the shore have lost part of their original geological context; note the precise location and surroundings of any unusual feature rather than assuming that nearby blocks came from the same bed.
Use the photographs below as a record of the original visit. Their lack of diagnostic captions and specimen determinations means they should not be used to identify named coral, shell or plant species. The well-known marine fossil beds at Abden belong to a different stretch of coast. Here, concentrate on natural surfaces, textures and the relationship between volcanic and sedimentary rocks; leave specimens in place unless the permissions described under ACCESS RIGHTS have been established.
Significant fossil discoveries, geological research and conservation milestones at Kinghorn.
1871 – Discovery and first public presentations
George Grieve discovered plant-bearing limestone at Pettycur. J.H. Balfour exhibited a fossil in May, and the locality was described and visited during the British Association meeting in Edinburgh that August, bringing its exceptional preserved plants to wider scientific attention.
1872 onwards – Anatomical descriptions
W.C. Williamson began a series of descriptions that helped establish the scientific importance of the Pettycur plants. Research relied on sections through mineralised material, revealing structures that could not be understood from external appearance alone.
1897 – The enigmatic reproductive structure
D.H. Scott described Cheirostrobus pettycurensis. Its complex spore-bearing organisation made it an important problem in understanding early sphenophytes and their relationships.
1908–1912 – Detailed botanical investigations
W.T. Gordon published detailed studies of the Pettycur plants, helping establish the anatomy of several lycopsids and ferns. His 1909 account also reported plant-bearing blocks associated with lavas in the cliffs, an important link between the loose beach material and the volcanic setting.
1950s–1972 – Reconstructing plants from serial sections
Studies using increasingly detailed sections and acetate peels clarified branching patterns and reproductive organs. Work on ferns was particularly important because successive views through a specimen revealed relationships that a single slice could miss.
1984–1987 – Age, mapping and depositional setting
Palynological work established an Asbian age, and detailed mapping and sedimentological research distinguished the different plant-bearing facies around Pettycur. The resulting interpretation linked vegetation, peat accumulation, transport and volcanic disturbance.
1988 – A supposed plant organ reinterpreted
Material previously identified as a pollen organ was reinterpreted as an arthropod coprolite. The revision showed that the mineralised deposits preserve evidence of interactions and decay within the plant assemblage as well as plant tissues themselves.
2019 – Reinvestigating historical slides
R. Neregato and J. Hilton re-examined Cheirostrobus using historical slide collections and its spores. The study refined interpretation of the reproductive structure while leaving the other organs of its whole plant unknown.
2024 – A modern reassessment of the Pettycur flora
A.C. Scott reviewed the anatomical plant record and a collection of more than 110 blocks. The study distinguished peat-like, ash-rich and charcoal-rich material, documented blocks incorporated in lava, and reassessed how volcanic activity and later mineralisation produced the exceptional preservation.
GEOLOGY
The rocks at Pettycur record an active volcanic landscape during the Viséan part of the Early Carboniferous. Basaltic lava flowed across the area, ash and other volcanic debris accumulated, and sediment and vegetation occupied the intervals and hollows within that changing landscape. The lavas belong to the Kinghorn Volcanic Formation of the Bathgate Group. Sedimentary formations elsewhere around Kinghorn belong to the Strathclyde Group, but that does not make the Pettycur volcanic succession part of that group.
The formation as a whole spans the Asbian–Brigantian, while palynological evidence places the famous Pettycur plant deposit in the Asbian. These are different scales of age assignment: the formation-wide range should not be applied as the age of every fossil block. A historical local description records about 25 m of volcanic rocks and mainly volcanogenic sediments, including lavas and sills. This is a local geological framework, not the thickness of a single limestone or a continuous fossil-bearing layer.
The Pettycur Limestone is particularly unusual because its plant-bearing material is not simply a horizontal bed between two lavas. Modern work records blocks incorporated in lava as well as loose blocks on the beach, and found no horizontal limestone layer. The proposed preservation history has several stages: plant material accumulated, volcanic activity incorporated parts of it into lava, and later calcite-rich water mineralised the tissues. Charcoal and ash record further variation in burning, transport and burial. This combination explains both the exceptional microscopic detail and the difficulty of reconstructing the precise origin of older beach collections.
Pettycur’s peat-like and ash-rich plant deposits preserve different associations, rather than one uniform fossil community. The historical Zygopterid Limestone was interpreted as transported vegetation deposited in a small lake, contrasting with the peat-like material. The nearby Kingswood plant locality has its own geological and botanical story and is not merged into this guide. Likewise, the marine succession farther north at Abden cannot be used as a bed-by-bed description of Pettycur Bay.
The Pettycur volcanic framework, plant-bearing facies and historical local horizons.
Scope and order. This account covers the Pettycur shore used by the original Kinghorn guide. It describes the formal volcanic framework followed by the documented local plant-bearing deposits. These deposits are not presented as a single, continuously exposed vertical stack: loose blocks, incorporation in lava, lateral variation and historical locality names complicate their relationships.
BATHGATE GROUP
The Bathgate Group is the formal parent of the Kinghorn Volcanic Formation. Earlier descriptions used names such as the Burntisland lavas. Sedimentary strata of the Strathclyde Group interdigitate with the volcanic rocks in the wider Kinghorn district, but they should not be substituted for the group assignment of the Pettycur lavas.
Kinghorn Volcanic Formation
The formation consists principally of basaltic lavas with volcaniclastic sedimentary rocks and subordinate tuffs. BGS describes a mainly subaerial origin with locally subaqueous conditions. The formation-wide age is Viséan, Asbian–Brigantian; the plant-bearing Pettycur deposits are assigned more specifically to the Asbian on palynological evidence. The reported NM spore biozone and DP subzone concern that fossil-bearing material, not a date for every exposure around the bay.
Local volcanic and sedimentary framework. The historical Pettycur section comprises about 25 m of volcanic igneous rocks, including lavas and sills, and mainly volcanogenic sediments. This figure describes the local section discussed in the palaeobotanical account. Much greater thicknesses quoted for the regional coastal succession or boreholes are not measurements of the plant-bearing limestone here. The broader formation’s marine interbeds and Abden limestones are also not an inventory of Pettycur fossil horizons.
Historical generalised section. The 1995 Geological Conservation Review reproduces a generalised log with basal shales, a thicker interval of lavas and ashes containing the Pettycur Limestone occurrence, limestones and ashy shales above, and further lavas and ashes at the top. This is a useful outline of the changing rock types, rather than a modern measured log for every exposure. The named plant-bearing facies cannot all be assigned unambiguously to individual layers from that simplified drawing; the limestone occurrence within the volcanic interval should not be redrawn as a continuous horizontal seam.
Pettycur Limestone: distribution and rank. This is the established name for the exceptional plant-bearing limestone material, including loose beach blocks and blocks enclosed within lava. Although a 2019 study used Member rank for it, a corresponding formal BGS member assignment has not been established here; it is therefore treated as a local deposit/facies name. Scott’s 2024 reassessment found no horizontal limestone layer. Older statements that the deposit had never been found in place need qualification because plant-bearing blocks have been documented within the volcanic succession.
Peat-rich facies. The classic material contains densely packed, calcite-permineralised plant remains with little mineral sediment, although some blocks contain charcoal. Much of the tissue represents aerial plant parts; roots are less conspicuous than in many younger coal-ball peats. Assemblages include mixed vegetation, fern-dominated material and blocks rich in lycopsid foliage and cones. Historically collected slides disproportionately represent the best-preserved peat facies and cannot be treated as an unbiased sample of the whole deposit.
Ash-rich and charcoal-rich facies. Other blocks contain progressively more volcanic ash, with charred plants especially prominent in ash-dominated material. Fern-rich peats can include layers of charred fern remains, while some highly ashy blocks contain only scattered plant fragments. These are preservation and depositional differences within the documented material; they are not newly named formal beds with demonstrated continuous boundaries.
Incorporation in lava and mineralisation. Scott interprets a sequence in which vegetation accumulated, parts of the plant-bearing material were incorporated into lava, and calcite-rich fluids later mineralised the tissues. Some blocks have associated calcite-filled pipes interpreted as former steam escape structures. The model helps explain how wet organic material, charcoal and volcanic rock came together, but does not imply that the plants grew in flowing lava or that every loose block has a known original position.
Zygopterid Limestone. The historical local framework distinguishes a second important plant-bearing deposit with abundant fusain, or fossil charcoal. It was interpreted as transported vegetation buried in a small lake in a volcanically disturbed landscape, rather than peat preserved where it accumulated. Zygopterid fern remains described from the Pettycur record include Metaclepsydropsis duplex, Diplolabis roemeri and Metadineuron ellipticum. The published facies interpretation should not be converted into a continuous layer that visitors can follow around the whole bay.
Harbour ‘Peat’. This is a historical local label for a further plant-bearing horizon reported with less well-preserved petrifactions and fusain. Its name distinguishes it from the main Pettycur Limestone material; it does not establish an undisturbed peat seam or a separately formalised member. A precise accessible thickness and continuous modern exposure are not established by the reviewed description.
Ashy Limestone 1. The first of three named ashy limestones in the historical local account contains less well-preserved petrifactions together with fusain. It records a further association of plant material and volcanic sediment. The available account does not justify assigning it a unique plant fauna or a new numerical thickness.
Ashy Limestone 2. This second named horizon is likewise reported with imperfectly preserved petrifactions and fusain. It is retained as a distinct documented local horizon, without assuming that its number specifies an independently verified modern exposure position or a diagnostic fossil assemblage.
Ashy Limestone 3. The third named ashy limestone completes the additional limestone horizons listed in the historical account. Plant petrifactions and fusain are recorded, but individual thickness, exact contacts and a separate diagnostic taxon list are not supplied by the inspected text. These three labels should not be used to construct an unsupported measured log.
Dolomitic mudstone with adpressions. Separate flattened plant remains were reported from dolomitic mudstone. The historical list includes Lepidodendron sp., Lepidocarpon cf. waltonii, Sphenopteris affinis, Sphenopteris sp., Sphenopteridium sp., Adiantites machanekii and Cardiopteridium sp. These adpression records are kept separate from the anatomically preserved organs in the peat-like limestones; they are not all parts of a single bed assemblage.
Interpreting the plant names. The following names are retained as historical records rather than a complete modern synonymy. Classic Pettycur studies assigned names to isolated stems, foliage, rooting organs, cones and reproductive structures. Recorded anatomical material includes Paralycopodites brevifolius, Lepidophloios scottii, Flemingites scottii, Stigmaria ficoides, Protocalamites pettycurensis, Protocalamostachys pettycurensis, Sphenophyllum insigne, Cheirostrobus pettycurensis, Botryopteris antiqua, Stauropteris burntislandica and Heterangium grievii. Association in the same deposit is not proof of organic attachment. In particular, the other organs of the Cheirostrobus whole plant remain unknown; it should not be reconstructed by simply attaching it to nearby Sphenophyllum material.
Geographical limits. The Kingswood Limestone is a separate nearby deposit. Its flora and modern ovule discoveries are not transferred to Pettycur. The Abden Bone Bed and marine limestone faunas north-east of Kinghorn belong to another coastal section. Neither the broad regional formation description nor the uncaptioned photographs from the old guide establishes named marine taxa on this Pettycur route.
References
British Geological Survey: Kinghorn Volcanic Formation, BGS Lexicon; Dean and colleagues’ formal formation account.
Cleal, C.J. and Thomas, B.A. (1995), Pettycur, Palaeozoic Palaeobotany of Great Britain, Geological Conservation Review 9. Historical local facies and plant records, including the account of Rex and Scott (1987).
Woodhall, D.G., in Stephenson and colleagues (2003), Burntisland to Kinghorn Coast, Geological Conservation Review 27. Regional volcanic context, with a broader geographical scope than this guide.
Neregato, R. and Hilton, J. (2019), Reinvestigation of the enigmatic Carboniferous sphenophyte strobilus Cheirostrobus Scott and implications of in situ Retusotriletes spores, International Journal of Plant Sciences 180, 811–833.
Scott, A.C. (2024), The anatomically preserved Early Carboniferous flora of Pettycur, Fife, Scotland, Proceedings of the Geologists’ Association 135, 389–415. Modern reassessment of the collections, plant associations and preservation.
SAFETY
Check tide times and weather before visiting and allow plenty of time to return across the bay. Water can close off the rocky shore before it appears high at the harbour. Wet basalt, seaweed and loose stones are slippery; avoid the shore during rough seas and do not rely on a scramble above the water as an escape route.
Keep clear of cliff faces, unstable blocks and overhangs. Do not climb to examine limestone enclosed in the lavas. Supervise children on the beach and avoid taking them onto awkward wet platforms. Follow local barriers and current access notices, and give feeding or resting birds plenty of space.
EQUIPMENT
Take sturdy footwear with good grip, weather protection, a phone, tide information, a hand lens and a camera. A small photographic scale and notebook help record possible plant structures and their setting. A hammer, pick or chisel is unnecessary for the observation-led visit described here.
CLEANING AND TREATING
Leave surfaces as found and record them photographically. If a specimen has been obtained with the relevant permission and consent, keep its location and geological notes with it and seek specialist advice before preparation. The diagnostic structures may be inside the matrix; careless breaking or polishing can destroy their relationships.
Do not use acid on plant-bearing limestone or attempt the laboratory peel methods described in scientific papers at home. Calcite is part of the preservation system. Photograph the unprepared specimen first and avoid coatings, consolidants or other treatment until an appropriate specialist has assessed it.
IDENTIFY YOUR FINDS
Need help identifying a fossil? Share clear photos, where you found it and its size with the community.
FURTHER READING
Pettycur: Geological Conservation Review palaeobotanical account
The anatomically preserved Early Carboniferous flora of Pettycur (2024)
Reinvestigating Cheirostrobus from Pettycur (2019)
Kinghorn Volcanic Formation: BGS geological framework
Pettycur Bay: Fife Coast and Countryside Trust visitor information
ACCESS RIGHTS
The Pettycur foreshore described here lies within the Firth of Forth Site of Special Scientific Interest. Visiting to look and photograph is different from taking fossils. Before removal, obtain the relevant rights-holder’s permission and confirm that the required NatureScot consent covers the activity. If permission or consent is unclear, leave fossils in place. Do not hammer or excavate exposures or disturb protected wildlife.
No standing fossil-removal permission is established by this guide. Public access to the shore, a walking route or a parking place does not itself grant collecting rights. Follow the Scottish Fossil Code and check current local signs and Fife Coast and Countryside Trust visitor information before setting out.
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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