Kintradwell Fossil Hunting

1827–1829 – Early scientific description
Roderick Murchison described fossiliferous rocks at Kintradwell and a cross-cutting vein about 2½ feet wide in a paper read in 1827 and published in 1829. The feature later became important in studies of injected sandstone; his original rock identification and stratigraphic correlations are historical interpretations.

1925 – Geological Survey documentation
H. H. Read, G. Ross and J. Phemister’s Golspie memoir illustrated the Kintradwell boulder beds and interpreted their sandstone blocks as Devonian. The origin of these reworked blocks has remained an important question in explaining the shore.

1961 – Slump structures investigated
John Crowell examined the folds and sliding structures around the sandstone-dyke part of the shore, using them to infer movement of sediment from the north-west.

1963 – Coast first notified for conservation
The broader coast that includes Kintradwell was first notified within the Brora–Helmsdale Coast Site of Special Scientific Interest, recognising the scientific value of these coastal exposures.

1983–1984 – Fault-controlled deposition developed
Kevin Pickering’s studies examined synsedimentary faulting and the fault-controlled submarine slope. They helped establish the framework for interpreting Kintradwell’s gravity-flow deposits, deformation and estimated formation thickness.

1985 – Sedimentary structures and fossil wood documented
Alister C. MacDonald’s thesis illustrated Kintradwell’s sandstone bedding, burrows, breccias, folds and slide surfaces, and described a well-preserved calcified log from slumped marine shale. It also developed the interpretation of Kintradwell’s mud-rich beds as approximate lateral equivalents of the Loth sandstones. This was a documentation milestone rather than a recorded date of collection.

1985–1986 – Local sections measured and correlated
Richard Vincent Tyson’s thesis, submitted in January 1985 and recorded in 1986, documented several Kintradwell sections and four marker beds around the main boulder-bed tongue. It demonstrated how lateral changes and inserted slump sheets complicate correlation, while separating background shale deposition from the coarser event beds.

1986 – Protected coast re-notified
Helmsdale Coast SSSI was re-notified on 12 December with a reduced area under the Wildlife and Countryside Act 1981. Kintradwell lies in its southern coastal section.

1989 – Soft-sediment deformation analysed
Alan Roberts distinguished small normal faults, south-directed slump folds and structures associated with gravity sliding at Kintradwell. The analysis showed how stretching and compression could develop within sediment moving down the same unstable slope.

1989 – Dinoflagellate correlation strengthened
H. F. Barron’s regional biostratigraphic study included four plotted Kintradwell samples and placed the local deposits in the Cymodoce Zone, helping to relate this shore to the wider Helmsdale succession.

1990–1991 – Ammonites documented in detail
Simon Brealey’s thesis, submitted in November 1990 for examination in 1991, documented Kintradwell ammonites including Rasenia evoluta. Their comparison with other successions supported an upper-Cymodoce interpretation.

1992 – A foraminifer named for Kintradwell
Francis John Gregory formally described Planularia kintradwellensis, named after Kintradwell Farm, and designated the Kintradwell Boulder Beds as its type section. The paper figured a holotype and paratype and stated that they were to be deposited in the Natural History Museum; it did not document completed deposition or accession numbers.

1993 – Age and sea-floor conditions reassessed
Paul Wignall and Kevin Pickering showed that Kintradwell and much of the Allt na Cuile sandstone succession were approximately contemporaneous. Their faunal and sedimentological work also clarified variations in bottom-water oxygenation and the rapid accumulation of sediment.

2003 – Sandstone injection separated from slumping
R. Jonk and colleagues mapped the sandstone dyke, showing that it cuts earlier slump folds and was subsequently faulted. Their structural and cement study interpreted injection as a later event, probably Tertiary, driven by rising basinal fluids during strike-slip movement.

2011 – Statutory notification reviewed
The Helmsdale Coast SSSI notification was reviewed on 2 February under the Nature Conservation (Scotland) Act 2004. This was a review of existing protection rather than the site’s first designation.

2014 – Separate formation rank affirmed
A. J. M. Barron and J. B. Riding’s revised Jurassic scheme accepted the Kintradwell Boulder Beds as a separate formation within the Sutherland Group, alongside the Allt na Cuile Sandstone and Helmsdale Boulder Beds formations.

SUTHERLAND GROUP

The Jurassic rocks of the East Sutherland outlier include a fault-margin marine succession exposed along this coast. At Kintradwell the relevant unit is the early Kimmeridgian Kintradwell Boulder Beds Formation. The six station descriptions below follow the shore geographically; they are not six beds in an established ascending vertical log.

Kintradwell Boulder Beds Formation

Rank, age, thickness and boundaries. Formation rank follows Barron and Riding’s 2014 scheme, which also recognises Allt na Cuile Sandstone and Helmsdale Boulder Beds as separate formations. The BGS Lexicon still lists Kintradwell as a member of the Helmsdale Boulder Beds Formation with the status “Pending Upgrade”; these are different rankings of the same unit, not two rock units. The estimated maximum formation thickness is about 85 m. Several local sections have been measured, but they cannot be joined into one continuously exposed 85 m shore log because beds vary laterally and slumping complicates their relationships. The transition from the underlying Clynekirkton unit is unexposed, and Barron’s account records no exposed contact with Allt na Cuile. Biostratigraphy places the main shore in the Cymodoce Zone; much of Allt na Cuile is approximately coeval, while the younger Helmsdale Boulder Beds follow in the regional succession.

Fissile siltstones, fossils and oxygenation. Many of the dark rocks described as shales consist mainly of silt-sized material and split into thin laminae, hence the term “paper siltstones”. Mud and terrestrial plant debris contribute to their dark colour. Crushed ammonites are common at some levels, with Amoeboceras subkitchini recorded in the siltstones and Rasenia evoluta and Amoeboceras kitchini in the southern section. The bivalves include Liostrea, Buchia, Parainoceramus, Solemya, Nicaniella and Palaeonucula, accompanied by the gastropod Semisolarium. The GCR account distinguishes a less diverse Buchia concentrica–Liostrea multiformis assemblage associated with restricted oxygen from more diverse assemblages indicating nearly normal oxygenation; the latter include the qualified identifications Nicaniella cf. eathiensis and Solemya cf. woodwardiana. Conditions therefore varied rather than remaining persistently anoxic.

Rapid deposition and changing bottom conditions. The diverse fauna in laminated sediment supports rapid accumulation during intervals when the bottom was oxygenated, rather than permanent exclusion of bottom-dwelling animals. Small probable bivalve escape structures at lower sandstone–siltstone contacts are also recorded in the Kintradwell account and indicate rapid burial. Such observations complement the quieter background deposition recorded by some of the shale-rich measured sections.

Station 1, NC 923 074: thin sandstone beds. Dark micaceous siltstones and shales, rich in plant debris, alternate with sandstones generally less than 30 cm thick. These sands have sharp bases, parallel and ripple lamination, and locally grading. Basal scour, prod and groove marks record transport by turbidity currents; ammonites, belemnites and pebbles could act as the tools making those marks. Burrows occur on bed soles and within some sands, including examples exposed by erosion of their roofs. Some burrowing animals may themselves have been transported into deeper water.

Station 1: thicker sands and early deformation. Thicker sandstone beds are more massive and contain convolute lamination, faults and folds formed before lithification. Some surfaces carry a strong lineation, particularly in the southern outcrops. Sandstone clasts, occasional rounded quartz pebbles and fairly common belemnites occur within them. Their sediment was swept off the shelf on the upthrown side of the Helmsdale Fault into deeper water on the downthrown side. The interpreted unstable slope lay at the foot of a fault scarp about 300 m west of the present shore section; that distance is neither a water depth nor a fault throw.

Sampled shale section near NC 926 074. Brealey described dark grey to black carbonaceous shales with silty laminae and fine sandstone stringers less than 1 cm thick. Harder calciferous sandy bands protected the softer shales, which yielded more ammonites. Belemnite guards, bivalves and occasional oysters were also present. The section was largely sand-covered and dipped northwards when recorded. Its ammonites include Rasenia evoluta and Amoeboceras rasenense, including specimens qualified as comparable with the latter, as well as Amoeboceras cricki; the informal “Evoluta” subdivision used in the thesis belongs within the upper Cymodoce Zone. Tyson’s separately measured A2 section in this area is described below.

Station 2, NC 925 074: sliding and the quartz-pebble reef. Bedding discordances can be followed for tens of metres. Some may represent sediment-filled slump scars; others are slide planes that follow bedding before passing to another horizon. Crowell inferred derivation from the north-west. Roberts distinguished normal faults downthrowing south or south-east, south-directed slump folds within wet sediment, and thrusts, low-angle slides and extensional faults associated with gravity sliding away from the Helmsdale Fault. The wider deformation suite includes pull-aparts, sand-filled fractures and overfolds.

The resistant sandstone reef around station 2 contains well-rounded quartz and quartzite pebbles, mainly 5–15 mm across, with occasional sandstone clasts, belemnites and shallow-marine bivalves. Rounding took place before the brief downslope transport. Reworking from older Jurassic sandstone, including the Brora sandstone succession, is a possible source for the pebbles and matrix sand. Their sporadic distribution indicates changing sediment supply: the same source was not reached by every flow.

Station 2: geometry of the sandstone dyke. The 2009 excursion describes a near-vertical calcite-cemented dyke up to 70 cm wide, traceable for about 100 m. Jonk and colleagues’ 2003 mapping records about 50 m of exposure, a width of roughly 0.2–1 m, and two overlapping, left-stepping segments trending approximately 120°, with small offshoots. These are separate published observations with different mapped extents. Their map deliberately exaggerates dyke width twofold. Millimetre-scale, branching and rejoining deformation bands occur within the injected sand. All these widths describe an intrusion, not a stratigraphic bed.

Dyke timing, source and cement. The dyke cuts across the earlier slump folds without sharing their deformation, and is itself cut by later small faults with both right- and left-lateral displacement. Its source is not exposed; underlying Oxfordian sandstone was favoured over the finer host sands. Jonk and colleagues interpreted injection as driven by ascending basinal fluids during strike-slip movement, probably in the Tertiary. This interpretation separates the dyke from Jurassic soft-sediment slumping. Grain-crushing deformation bands developed before pervasive carbonate cementation. Early non-ferroan calcite was associated with hot fluids, followed by lower-temperature ferroan cement that also affected the host sandstone.

Station 3, NC 926 074: a reworked breccia boulder. An approximately 2 m boulder rests on and deforms laminated sandstone whose thickness varies laterally. The boulder is itself a breccia of sandstone blocks in coarse sand with small quartz pebbles, resembling material at Allt Choll. It records reworking after sufficiently early lithification for the breccia to survive transport. Cementation by fluids rising along the active fault is a proposed explanation for that early hardening, rather than a demonstrated history for every clast.

Station 4, NC 926 075: a slump overfold. An isolated sandstone exposure, often surrounded by sand, contains a conspicuous overfold. Rounded quartz pebbles occur alongside angular sandstone clasts. These contrasting textures indicate at least two sediment sources or different degrees of lithification in the source rocks: loose rounded pebbles could be released from less consolidated material while angular blocks came from harder sandstone.

Station 5, NC 927 076: a sliding sediment sheet. Interbedded sandstone and shale are capped by convolutely laminated sandstone. At the base, two or more slide planes enclose intensely deformed shale and thin sandstone layers folded into flat-lying isoclinal folds. The relationships record a sheet of sediment moving downslope away from the fault. Sand and seaweed commonly obscure the base.

Station 6, NC 928 076, and the boulder beds near NC 929 077. Lenticular, matrix-supported boulder beds alternate with siltstones, shales and thin sandstones. Angular to rounded clasts of white or grey sandstone show parallel lamination and cross-bedding, while surrounding sediment is compacted and deformed around them. One conspicuous block measures about 6 × 7 m in the excursion account; the GCR describes a large boulder up to 7 m across. These are boulder dimensions, not bed thicknesses. The large block includes cross-bedded sandstone with concentrations of small green mudstone flakes.

Competing sandstone-clast interpretations. The GCR account, following Pickering, favours older Jurassic sandstone sources, and the 2024 regional synthesis retains a Jurassic interpretation. The 2009 excursion instead argues that many feldspathic blocks, especially those with fluvial cross-bedding and green mudstone flakes, are Devonian. It notes that most shell-like slits in the local sandstone blocks are weathered clay flakes, while allowing possible Jurassic clasts. Mud-filled veins and disintegrating block margins could reflect weakly lithified material at emplacement, or later fluid-assisted fracturing and bleaching. The disagreement remains relevant: neither apparent shell moulds nor a block’s present pale colour alone resolves its source age.

Additional photographed sandstone structures. MacDonald recorded isolated thin sandstone lenses with eroded bases, grading and cross-lamination at NC 921 072, south-west of the main excursion stations. At NC 926 074, an illustrated bed passes from lower parallel lamination into cross-lamination, interpreted as the b and c divisions of a turbidite; another photograph shows horizontal burrows on a sandstone top. A thick graded bed there is overlain by thinner beds in a thinning-upward compound unit. Near Kintradwell Point, unusual climbing dune-like structures were reported near the base of one bed. A possible wave ripple at NC 926 074 and irregular bedding at NC 928 076 suggest some wave influence, although those interpretations are tentative and do not establish a particular water depth.

Breccia matrices and local reworking. Both sand-matrix and mud-matrix cobble breccias, with matrix-supported clasts in both examples, are illustrated at NC 926 074. A field sketch shows brecciated material passing laterally into contorted bedding, with distorted clasts near the edge, interpreted as local slope failure and reworking of nearby sediment. Thus coarse deposits need not all represent the same transport process or solely much older boulders. A distinctive sandstone-clast type described from Kintradwell’s breccias is light to dark grey, quartz-rich and coarsely calcite-cemented, sometimes with rounded quartz granules, clay pellets and bivalve fragments. MacDonald’s Jurassic interpretation of such material is part of the provenance debate rather than proof of a single source for every block.

Rotational sliding, apparent onlap and overturned limbs. Photographs at NC 926 074 show relatively steep beds enclosed by flatter beds, interpreted as possible rotational sliding. Another exposure has silty layers apparently onlapping a sharp, near-horizontal discontinuity. Despite resembling cross-bedding, MacDonald suggested that this could be a detachment surface, perhaps the flat base of a curved fault; little deformation was visible immediately above or below it. Tight soft-sediment folds with overturned lower limbs, reverse faults and thrusts show compression during movement. Their varying orientations allow movement into local depressions as well as down the broader submarine slope, with compression near the bases of slides.

Calcified wood. The uncompacted log illustrated by MacDonald from slumped marine shale has a long diameter of about 15 cm. Bark, cellular wood structure and concentric growth rings were reported as well preserved; the rings suggested a tree roughly 30 years old. Early calcification was interpreted to have preserved its shape before compaction. This record has no verified tree species, collection date or museum accession, and its diameter is a specimen measurement rather than a sedimentary thickness.

Tyson’s measured shore sections: how to read them. The following A-numbered sections are a separate survey from the six excursion stations. They record particular historical exposures and cannot be treated as a simple complete formation log. A2 describes the western beach near NC 926 074; A3–A5 lie around the main boulder-bed tongue on the eastern beach, centred near NC 927 075, about 100 m east of the burn mouth. A3 and A4 show partly equivalent strata on opposite sides of the tongue. A5 is a displaced slump sheet inserted after Bed III and before Bed IV. Their logged thicknesses must therefore not be added together.

A2: the western background succession, approximately 37 m logged. Tyson deliberately chose a line through chiefly grey to black organic-rich shale, avoiding many of the coarse lenticular deposits and intensely slumped horizons. Sandstone makes up about 16% of the section, concentrated in the lower 8.6 m. Westwards these lower sands pass into discontinuous, locally overlapping sandstone and subordinate boulder-bed lenses. The boulder beds have a sandy matrix around subangular to subrounded cobbles and boulders of bedded grey quartz sandstone. Some pebbly beds contain rounded quartz pebbles up to about 3 cm across and conspicuous coarse shell debris, including large belemnite guards. Near the top of A2, a poorly sorted, calcite-cemented, shelly sandstone slump contains rounded metaquartzite pebbles and sandstone clasts and is strongly overfolded towards the south-south-east.

A2: shale laminae, fossils and cemented bands. Coarse silt and very fine sand occur in discrete laminae, with sandstone stringers less than 1 cm thick. Many ammonites and bivalves are preserved as decalcified impressions, while some robust shells, including large oysters, are better preserved. Bioturbation was rarely seen in the logged shale and was chiefly bedding-parallel. Lenticular calcite-cemented bands represent altered shale or muddy sandstone whose original texture can be obscured by cement. At the sampled horizon K109, incipient cone-in-cone calcite grew beside and disrupted carbonaceous laminae. K109 is a sample label rather than a formal bed or member name.

A3 and A4: the eastern marker-bed sections. A3, west of the boulder-bed tongue, contains 13.47 m of logged strata with relatively little disruption and about 20% discrete sandstone. A4, on the more deformed eastern side, has 12.69 m logged. A4’s correlated interval is slightly thicker than its counterpart within A3, plausibly because of measurement uncertainty and differential compaction around variably cemented sand stringers. Fine to very fine, woody or carbonaceous sandstones form the principal markers. Their abundant calcite cement produces a lustre-mottled appearance and can partly obscure the original sedimentary structures.

Bed I. This prominent cemented sandstone reef in A3 continues uninterrupted beneath the boulder-bed tongue to form the base of A4. Convolute bedding and pull-apart structures, including incipient ball-and-pillow deformation, show how the sand was disrupted while still soft. Adjacent thin sand and shale layers also record movement. The published log identifies especially carbonaceous sandstone at this level; no individual numerical bed thickness is stated here.

Bed II and the overlying shale interval. Another conspicuous cemented sandstone reef in A3 displays overfolding, convolute bedding and pull-aparts, with nearby dislocation surfaces and small slump folds. Its less massive, more shaly equivalent in A4 was bent into a broad arch by emplacement of, and compaction around, the boulder-bed tongue; that arch is now breached. Above it, thin boulder lenses occur within shale, followed higher up by an overfolded shelly fine calcareous sandstone and a boulder bed approximately level with Bed III in A3. A4 also shows a downwarped thin sandstone beneath a thin boulder bed, with scattered pebbles and cobbles in the underlying shale. In the higher shale interval, sand laminae become more frequent and thicker upwards, reaching 4 cm in the logged exposure.

Bed III. The third upper cemented sandstone marker in A3 lies above the shale interval over Bed II. Like the other markers it is fine to very fine, calcareous and carbonaceous. Its position provides a useful limit on the timing of local mass movement: the A5 slump sheet arrived after Bed III had been deposited, while the overlying Bed IV later covered the correlated sections. The boulder bed near this level in A4 illustrates how the local facies change across the shore.

A5: the displaced slump sheet, 9.43 m measured. This unit lies west of and stratigraphically above the main boulder-bed tongue. Its beds strike at an angle to A3, and much of the exposure was hidden beneath beach shingle. A prominent upper overfold suggested movement from the east-north-east, a direction applying to this sheet rather than all flows at Kintradwell. White, pale grey or cream, fine-grained calcite-cemented sandstone bands account for about 20% of the measured interval. They thin in both directions along strike, with an estimated maximum lateral extent of about 10 m, and many contain abundant shell debris. Convolutions, small faults, channels and water-escape structures accompany the slumping.

A5 internal beds: K20 and the sandstone above K25. Prominent flame structures occur in the sandstone labelled K20. The sandstone above the K25 shale has a strongly deformed, shell-rich basal layer with angular sandstone clasts, including one 17 cm long, overlain by more regularly bedded shelly sand with convolution in its upper 5 cm. The K-labels identify sampled horizons, not formal stratigraphic units. Tyson also described a sandstone whose lower 11 cm contains belemnite and bivalve fragments with small rounded sandstone clasts, and recorded a single in-situ clast identified as “granite”. That isolated identification should not be generalised to the whole deposit. Larger clasts higher in the bed may reflect reverse grading during temporary fluidisation, an interpretation linked to the underlying water-escape structures.

Upper A5: channel and boulder lens. The uppermost sandstone is largely parallel-bedded with shell-rich layers, but contains local channels. One was measured as 60 cm × 3 m and has a 5 cm basal lag of coarse shell debris, passing upwards into fine, finely bedded sandstone with small faults. Near the closure of the plunging overfold, an intercalated, possibly channelised boulder bed is 24 cm thick and contains sandstone clasts up to 22 cm across. These are measurements of particular features in the A5 sheet.

The main boulder-bed tongue. This unusually clast-rich body measures approximately 1–2 m × 3 m × 15 m. In contrast to the commonly matrix-supported boulder beds, it is a clast-supported breccia of angular to subangular fine, cemented quartz sandstone in a sandy matrix. The blocks range from less than 5 cm to about 1.3 m in long dimension and show parallel or planar cross-bedding. Emplacement appears to have bent the underlying beds rather than eroded them. Its dimensions describe the whole tongue, not one boulder or a uniform thickness across the shore.

Bed IV. This boulder bed caps the correlated A3–A5 sections. It is clast-rich but matrix-supported, with angular to subangular grey, planar cross-bedded, cemented quartz-sandstone blocks reaching about 1 m and averaging about 30 cm. Very fine to fine calcite-cemented sand forms the matrix: comparatively clean and somewhat shelly at the base, muddier and more carbonaceous above. Some blocks weather red. Clasts show a weak roughly north–south preferred orientation, and calcite veins cut both them and the matrix. Poor exposure made the apparent upward concentration of larger clasts uncertain. Tyson allowed Jurassic and/or Devonian sandstone sources, reinforcing the need to retain the clast-provenance question.

Nearby Kintradwell-area context: A1 at the burn, NC 921 070. At the north-eastern end of Brora Links, south-west of the Kintradwell Burn mouth, Tyson measured about 6.8 m, roughly two-thirds shale, and assigned the age tentatively to the Cymodoce Zone. Two amalgamated cemented sandstones near the top include an upper fine sandstone with poorly defined lower ripples and upper convolutions, and a lower sandstone graded from medium to fine grain size, with basal shell debris and wood and occasional shale clasts near its top. Sandstones just south-west of A1 contain matrix-supported sandstone pebbles and boulders and shell-rich surfaces with brachiopods, bivalves, ammonites and belemnites. This is a separately located exposure, not station 1 of the shore excursion.

Nearby stream and bluff sections: A6 and A7. A6, in Allt Garbh-Chlais at NC 925 075, records 5.19 m below a small road bridge: shale with abundant uncemented fine-sand laminae and a little over 9% thin sandstone, with plant fossils and oysters. A7, at Kintradwell Bluff near NC 926 077, records about 5.5 m, partly obscured by grass. Its basal composite fine calcite-cemented sandstone contains belemnite and oyster debris, pebbly lenses of sandstone clasts and shale partings less than 3 cm thick. Overlying shale carries mainly approximately 1 cm fine-sand bands, locally up to 4 cm, some weakly iron-cemented but still friable. Both sections were assigned tentatively to the Cymodoce Zone. They supply geological context away from the principal foreshore stations, rather than additional visitor access instructions.

Biostratigraphic and microfossil control. Barron’s plotted Kintradwell samples are 47 at NC 9243 0739, 49 at NC 9264 0753, 50 at NC 9264 0756 and 51 at NC 9267 0759. The published figure is a schematic regional composite, not a numbered bed log. Gregory’s 1992 description of Planularia kintradwellensis cites the Kintradwell Boulder Beds as the type section and prints a section reference of NC 9255 0713. It reports 109 Helmsdale specimens, figures a holotype and paratype, and proposes deposition in the Natural History Museum without accession numbers. The species’ wider local Cymodoce–Mutabilis range and broader British Baylei–Mutabilis range should not be used to extend the age of every Kintradwell host bed into the Mutabilis Zone.

References
MacDonald, A. C. and Trewin, N. H. (2009), Excursion 3: The Upper Jurassic of the Helmsdale area, especially itinerary 3.1.
Cox, B. M. (2001), Helmsdale, in British Upper Jurassic Stratigraphy, Geological Conservation Review 21.
Barron, H. F. (1989), Dinoflagellate cyst biostratigraphy and palaeoenvironments of the Upper Jurassic (Kimmeridgian to basal Portlandian) of the Helmsdale region.
Barron, A. J. M. and Riding, J. B. (2014), A revision of the Jurassic (Bathonian to Oxfordian) lithostratigraphy of the onshore Moray Firth Basin, north-east Scotland, accepted manuscript.
Brealey, S. (1990–1991), The Late Oxfordian to Kimmeridgian History of the Rob Roy and Ivanhoe Fields, Outer Moray Firth, thesis, Kintradwell account and taxonomic material.
Gregory, F. J. (1992), Planularia kintradwellensis sp. nov. (Foraminifera), a distinctive biostratigraphical marker species for the Lower Kimmeridgian of the U.K., Journal of Micropalaeontology 11, 135–140.
Jonk, R., Duranti, D., Parnell, J., Hurst, A. and Fallick, A. E. (2003), The structural and diagenetic evolution of injected sandstones: examples from the Kimmeridgian of NE Scotland.
MacDonald, A. C. (1985), Kimmeridgian and Volgian fault-margin sedimentation in the northern North Sea area, University of Strathclyde PhD thesis, submitted September 1985.
Tyson, R. V. (1986), Palynofacies and sedimentology of some Late Jurassic sediments from the British Isles and northern North Sea, Open University PhD thesis, submitted January 1985; Kintradwell sections, pp. 326–352.
Morton and colleagues (2024), Jurassic: Pangaea break-up and birth of the Atlantic Ocean, The Geology of Scotland, fifth edition.
British Geological Survey, Kintradwell Boulder Beds Member Lexicon entry, status Pending Upgrade.