The Ballagan Formation is a geologic formation in Scotland and England. It preserves fossils dating back to the early part of the Carboniferous period (Tournaisian – early Visean).[1] Its name comes from the "Ballagan Beds" of Ballagan Glen, near Strathblane, which has a good example of this geological formation.[2]

Ballagan Formation
Stratigraphic range: TournaisianVisean
Exposure of alternating siltstone and dolomite layers of the Ballagan Formation in the bank of Tarras Water
TypeFormation
Unit ofInverclyde Group
UnderliesClyde Sandstone Formation
OverliesKinnesswood Formation
AreaCentral Lowlands, Northern England
Thickness~900 m
Lithology
Primarymudstone, cementstone, siltstone
Othersandstone
Location
RegionScotland
CountryUnited Kingdom
Type section
Named forBallagan Glen
Named byBrowne, 1980

The Ballagan Formation was historically known as the Cementstone Group,[3][4] but more recently it has been placed as the middle formation of the Inverclyde Group.[5] This change was motivated by the recognition that the youngest parts of the Devonian Upper Old Red Sandstone (now known as the Kinnesswood Formation) were geologically continuous with the lowest parts of the Lower Carboniferous Calciferous Sandstone Measures (now known as the Ballagan and Clyde Sandstone formations). This interval of Devonian-Carboniferous overlap was named the Inverclyde Group, and the cementstone-rich "drab beds" in the middle of the group were renamed to the Ballagan Formation.[6] In Lothian, the Ballagan and Clyde Sandstone formations are sometimes known as the Tyninghame Formation.[7]

Fossil sites

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Many localities of the Ballagan Formation preserve exceptional fossils. The majority of fossiliferous sites are in the Midland Valley (particularly the Scottish Borders and East Lothian), in the southeast corner of Scotland.[5][8]

One of the earliest sites to be studied was the fish bed at Foulden, which hosts many well-preserved fish fossils, notably including endemic actinopterygians (ray-finned fish) and the first complete skeleton of a rhizodont.[9][10] Plants and arthropods also form a significant portion of Foulden fossils.[11][12][13][14] This site and its fish fossils were publicized by E.I. White in 1927,[15] and further excavations were performed by Stan Wood in 1980-1981.[16] The Foulden fish bed was the primary theme for volume 76 of the Transactions of the Royal Society of Edinburgh: Earth Sciences journal, published in 1985.[16][17][18]

Willie's Hole, near Chirnside, is another site known for its high quality of preservation. It was initially recognized for its crustacean fossils, forming "shrimp beds" akin to those observed throughout the later Scottish Carboniferous.[19] Willie's Hole has continued to produce well-preserved fossils of arthropods, fish, and partial tetrapod skeletons.[5][20][21][22]

 
Ballagan Formation outcrop at Spouts Burn, in southwest Scotland near Auchenrock Glen and Dumbarton

By far the largest exposures of the Ballagan Formation occur along the coastal end cliffs of Burnmouth.[5][23][24] Tetrapod, fish, and arthropod fragments are common in several layers at Burnmouth, not just in fine-grained overbank deposits[20][22][25][26] but also coarse river channel conglomerates, an unusual mode of preservation.[27][28]

Tetrapod fossils have been found in the vicinity of Tantallon Castle.[5][29] Additional Midland Valley sites include Crumble Edge (along Whiteadder Water),[30] Coldstream,[5][31] Cockburnspath,[32][5] Cove (in Berwickshire),[31] and Whitrope Burn (near Hawick).[33] A few locales in nearby Northumberland, England encompass fossil-bearing outcrops of the Ballagan Formation, such as Berwick-upon-Tweed[34][35] Barrow Scar (near Alwinton),[31] and a borehole core at Norham.[23][24]

Some sites are also found along the west coast of Scotland. Auchenreoch Glen, near Dumbarton, was the collection site for the nearly complete type fossil of Pederpes finneyae, which was the oldest named tetrapod of the Carboniferous upon its discovery.[36] Diverse assemblages of fish teeth and other microfossils have been found at Ayrshire[37][31] and at Hawk's Nib and Mill Hole, on the Isle of Bute.[38]

Paleobiota

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The Ballagan Formation preserves a plethora of tetrapod, fish, and invertebrate fossils, reconstructing one of the most diverse continental ecosystems known from the Tournaisian stage. A variety of plant megafossils and spores are known from the Ballagan Formation.[11][39][37][40][41]

Tetrapods

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Fish

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Invertebrates

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See also

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References

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  1. ^ British Geological Survey. "Ballagan Formation". BGS Lexicon of Named Rock Units. Retrieved 8 March 2018.
  2. ^ MacDonald, Hugh (1910). Rambles Round Glasgow (New ed.). Glasgow: John Smith. p. 382.
  3. ^ Belt, Edward S.; Freshney, Edward C.; Read, William A. (1967). "Sedimentology of Carboniferous Cementstone Facies, British Isles and Eastern Canada". The Journal of Geology. 75 (6): 711–721. doi:10.1086/627295. ISSN 0022-1376. S2CID 140699667.
  4. ^ Scott, W. B. (1986). "Nodular carbonates in the Lower Carboniferous, Cementstone Group of the Tweed Embayment, Berwickshire: evidence for a former sulphate evaporite facies". Scottish Journal of Geology. 22 (3): 325–345. doi:10.1144/sjg22030325. ISSN 0036-9276. S2CID 129888604.
  5. ^ a b c d e f g h i j k l m n o p q r s Smithson, Timothy R.; Wood, Stanley P.; Marshall, John E. A.; Clack, Jennifer A. (20 March 2012). "Earliest Carboniferous tetrapod and arthropod faunas from Scotland populate Romer's Gap". Proceedings of the National Academy of Sciences. 109 (12): 4532–4537. Bibcode:2012PNAS..109.4532S. doi:10.1073/pnas.1117332109. ISSN 0027-8424. PMC 3311392. PMID 22393016.
  6. ^ a b c d Brown, M.A.E. (1980). "The Upper Devonian and Lower Carboniferous (Dinantian) of the Firth of Tay, Scotland". Report of the Institute of Geological Sciences. 80 (9): 1–13.
  7. ^ Andrews, Julian A.; Ghulam, Nabi (1994). "Lithostratigraphy of the Dinantian Inverclyde and Strathclyde Groups, Cockburnspath Outlier, East Lothian – North Berwickshire". Scottish Journal of Geology. 30 (2): 105–119. doi:10.1144/sjg30020105. S2CID 129170097.
  8. ^ Millward, David; Davies, Sarah J.; Brand, Peter J.; Browne, Michael A. E.; Bennett, Carys E.; Kearsey, Timothy I.; Sherwin, Janet E.; Marshall, John E. A. (2018). "Palaeogeography of tropical seasonal coastal wetlands in northern Britain during the early Mississippian Romer's Gap". Earth and Environmental Science Transactions of the Royal Society of Edinburgh. 109 (1–2): 279–300. doi:10.1017/S1755691018000737. ISSN 1755-6910. S2CID 134002840.
  9. ^ a b c d e f g Gardiner, B. G. (1985). "Actinopterygian fish from the Dinantian of Foulden, Berwickshire, Scotland". Transactions of the Royal Society of Edinburgh: Earth Sciences. 76 (1): 61–66. doi:10.1017/S0263593300010312. ISSN 0263-5933. S2CID 129150300.
  10. ^ a b c Andrews, S. M. (1985). "Rhizodont crossopterygian fish from the Dinantian of Foulden, Berwickshire, Scotland, with a re-evaluation of this group". Transactions of the Royal Society of Edinburgh: Earth Sciences. 76 (1): 67–95. doi:10.1017/S0263593300010324. ISSN 0263-5933. S2CID 129928937.
  11. ^ a b Scott, Andrew C.; Meyer-Berthaud, Brigitte (1985). "Plants from the Dinantian of Foulden, Berwickshire, Scotland". Earth and Environmental Science Transactions of the Royal Society of Edinburgh. 76 (1): 13–20. doi:10.1017/S0263593300010245. ISSN 1473-7116. S2CID 131329370.
  12. ^ a b c Briggs, D. E. G.; Clarkson, E. N. K. (1985). "Malacostracan Crustacea from the Dinantian of Foulden, Berwickshire, Scotland". Transactions of the Royal Society of Edinburgh: Earth Sciences. 76 (1): 35–40. doi:10.1017/S0263593300010270. ISSN 0263-5933. S2CID 130343194.
  13. ^ a b c d e Waterston, Charles D. (1985). "Chelicerata from the Dinantian of Foulden, Berwickshire, Scotland". Transactions of the Royal Society of Edinburgh: Earth Sciences. 76 (1): 25–33. doi:10.1017/S0263593300010269. ISSN 0263-5933. S2CID 128557225.
  14. ^ a b Almond, John E. (1985). "A vermiform problematicum from the Dinantian of Foulden, Berwickshire, Scotland". Transactions of the Royal Society of Edinburgh: Earth Sciences. 76 (1): 41–47. doi:10.1017/S0263593300010282. ISSN 0263-5933. S2CID 128478847.
  15. ^ a b c d e f g h i White, Errol Ivor (1927). "XI.—The Fish-Fauna of the Cementstones of Foulden, Berwickshire". Transactions of the Royal Society of Edinburgh. 55 (1): 255–287. doi:10.1017/S008045680001632X. ISSN 0080-4568. S2CID 130677909.
  16. ^ a b c d e Wood, S. P.; Rolfe, W. D. Ian (1985). "Introduction to the palaeontology of the Dinantian of Foulden, Berwickshire, Scotland". Transactions of the Royal Society of Edinburgh: Earth Sciences. 76 (1): 1–6. doi:10.1017/S0263593300010221. ISSN 0263-5933. S2CID 130746007.
  17. ^ Anderton, R. (1985). "Sedimentology of the Dinantian of Foulden, Berwickshire, Scotland". Transactions of the Royal Society of Edinburgh: Earth Sciences. 76 (1): 7–12. doi:10.1017/S0263593300010233. ISSN 0263-5933. S2CID 130602435.
  18. ^ a b Clarkson, E. N. K. (1985). "Palaeoecology of the Dinantian of Foulden, Berwickshire, Scotland". Transactions of the Royal Society of Edinburgh: Earth Sciences. 76 (1): 97–100. doi:10.1017/S0263593300010336. ISSN 0263-5933. S2CID 130577679.
  19. ^ a b c d e f g h i j k l Cater, J. M. L.; Briggs, D. E. G.; Clarkson, E. N. K. (1989). "Shrimp-bearing sedimentary successions in the Lower Carboniferous (Dinantian) Cementstone and Oil Shale Groups of northern Britain". Transactions of the Royal Society of Edinburgh: Earth Sciences. 80 (1): 5–15. doi:10.1017/S0263593300012232. ISSN 0263-5933. S2CID 129598844.
  20. ^ a b c d e f g Clack, Jennifer A.; Bennett, Carys E.; Carpenter, David K.; Davies, Sarah J.; Fraser, Nicholas C.; Kearsey, Timothy I.; Marshall, John E. A.; Millward, David; Otoo, Benjamin K. A.; Reeves, Emma J.; Ross, Andrew J.; Ruta, Marcello; Smithson, Keturah Z.; Smithson, Timothy R.; Walsh, Stig A. (5 December 2016). "Phylogenetic and environmental context of a Tournaisian tetrapod fauna". Nature Ecology & Evolution. 1 (1): 2. doi:10.1038/s41559-016-0002. hdl:2381/40933. ISSN 2397-334X. PMID 28812555. S2CID 22421017.
  21. ^ a b Smithson, Timothy R.; Clack, Jennifer A. (2017). "A new tetrapod from Romer's Gap reveals an early adaptation for walking". Earth and Environmental Science Transactions of the Royal Society of Edinburgh. 108 (1): 89–97. doi:10.1017/S1755691018000075. ISSN 1755-6910. S2CID 133836365.
  22. ^ a b c d Ross, Andrew J.; Edgecombe, Gregory D.; Clark, Neil D. L.; Bennett, Carys E.; Carrió, Vicen; Contreras-Izquierdo, Rubén; Crighton, Bill (2017). "A new terrestrial millipede fauna of earliest Carboniferous (Tournaisian) age from southeastern Scotland helps fill 'Romer's Gap'". Earth and Environmental Science Transactions of the Royal Society of Edinburgh. 108 (1): 99–110. doi:10.1017/S1755691018000142. ISSN 1755-6910. S2CID 135183999.
  23. ^ a b Kearsey, Timothy I.; Bennett, Carys E.; Millward, David; Davies, Sarah J.; Gowing, Charles J.B.; Kemp, Simon J.; Leng, Melanie J.; Marshall, John E.A.; Browne, Michael A.E. (2016). "The terrestrial landscapes of tetrapod evolution in earliest Carboniferous seasonal wetlands of SE Scotland". Palaeogeography, Palaeoclimatology, Palaeoecology. 457: 52–69. Bibcode:2016PPP...457...52K. doi:10.1016/j.palaeo.2016.05.033. hdl:2381/41464.
  24. ^ a b Bennett, Carys E.; Kearsey, Timothy I.; Davies, Sarah J.; Millward, David; Clack, Jennifer A.; Smithson, Timothy R.; Marshall, John E. A. (2016). Fielding, Chris (ed.). "Early Mississippian sandy siltstones preserve rare vertebrate fossils in seasonal flooding episodes". Sedimentology. 63 (6): 1677–1700. doi:10.1111/sed.12280. hdl:2381/40282. S2CID 54201423.
  25. ^ a b Challands, Tom J.; Smithson, Timothy R.; Clack, Jennifer A.; Bennett, Carys E.; Marshall, John E. A.; Wallace-Johnson, Sarah M.; Hill, Henrietta (2 November 2019). "A lungfish survivor of the end-Devonian extinction and an Early Carboniferous dipnoan radiation". Journal of Systematic Palaeontology. 17 (21): 1825–1846. doi:10.1080/14772019.2019.1572234. ISSN 1477-2019. S2CID 91623116.
  26. ^ a b c d e f g h i j k l Otoo, Benjamin K. A.; Clack, Jennifer A.; Smithson, Timothy R.; Bennett, Carys E.; Kearsey, Timothy I.; Coates, Michael I. (2019). Ruta, Marcello (ed.). "A fish and tetrapod fauna from Romer's Gap preserved in Scottish Tournaisian floodplain deposits". Palaeontology. 62 (2): 225–253. doi:10.1111/pala.12395. S2CID 134566755.
  27. ^ a b c d e f g h Clack, Jennifer A.; Bennett, Carys E.; Davies, Sarah J.; Scott, Andrew C.; Sherwin, Janet E.; Smithson, Timothy R. (3 January 2019). "A Tournaisian (earliest Carboniferous) conglomerate-preserved non-marine faunal assemblage and its environmental and sedimentological context". PeerJ. 6: e5972. doi:10.7717/peerj.5972. ISSN 2167-8359. PMC 6321757. PMID 30627480.
  28. ^ a b Clack, Jennifer A.; Porro, Laura B.; Bennett, Carys E. (2017). "A Crassigyrinus -like jaw from the Tournaisian (Early Mississippian) of Scotland". Earth and Environmental Science Transactions of the Royal Society of Edinburgh. 108 (1): 37–46. doi:10.1017/S1755691018000087. ISSN 1755-6910. S2CID 220421588.
  29. ^ a b Chen, Donglei; Alavi, Yasaman; Brazeau, Martin D.; Blom, Henning; Millward, David; Ahlberg, Per E. (March 2017). "A partial lower jaw of a tetrapod from "Romer's Gap"". Earth and Environmental Science Transactions of the Royal Society of Edinburgh. 108 (1): 55–65. doi:10.1017/S1755691018000099. ISSN 1755-6910. S2CID 135127547.
  30. ^ a b Bicknell, Russell D. C.; Pates, Stephen (19 November 2019). "Xiphosurid from the Tournaisian (Carboniferous) of Scotland confirms deep origin of Limuloidea". Scientific Reports. 9 (1): 17102. Bibcode:2019NatSR...917102B. doi:10.1038/s41598-019-53442-5. ISSN 2045-2322. PMC 6863854. PMID 31745138.
  31. ^ a b c d e f g h i j k l Smithson, Timothy R.; Richards, Kelly R.; Clack, Jennifer A. (2016). Johanson, Zerina (ed.). "Lungfish diversity in Romer's Gap: reaction to the end-Devonian extinction". Palaeontology. 59 (1): 29–44. doi:10.1111/pala.12203. S2CID 55266403.
  32. ^ Andrews, Julian E.; Turner, Michael S.; Nabi, Ghulam; Spiro, Baruch (1991). "The anatomy of an early Dinantian terraced floodplain: palaeo-environment and early diagenesis". Sedimentology. 38 (2): 271–287. doi:10.1111/j.1365-3091.1991.tb01260.x. ISSN 0037-0746.
  33. ^ a b c d e f g h i j k l m n o p q Richards, Kelly R.; Sherwin, Janet E.; Smithson, Timothy R.; Bennion, Rebecca F.; Davies, Sarah J.; Marshall, John E. A.; Clack, Jennifer A. (2017). "Diverse and durophagous: Early Carboniferous chondrichthyans from the Scottish Borders". Earth and Environmental Science Transactions of the Royal Society of Edinburgh. 108 (1): 67–87. doi:10.1017/S1755691018000166. ISSN 1755-6910. S2CID 133929085.
  34. ^ Bennett, C.E.; Howard, A.S.; Davies, S.J.; Kearsey, T.I.; Millward, D.; Brand, P.J.; Browne, M.A.E.; Reeves, E.J.; Marshall, J.E.A. (2017). "Ichnofauna record cryptic marine incursions onto a coastal floodplain at a key Lower Mississippian tetrapod site". Palaeogeography, Palaeoclimatology, Palaeoecology. 468: 287–300. doi:10.1016/j.palaeo.2016.12.018. hdl:2381/40371.
  35. ^ a b c d e f g h i j k l m n o p q Bennett, C.E.; Kearsey, T.I.; Davies, S.J.; Leng, M.J.; Millward, D.; Smithson, T.R.; Brand, P.J.; Browne, M.A.E.; Carpenter, D.K.; Marshall, J.E.A.; Dulson, H.; Curry, L. (2021). "Palaeoecology and palaeoenvironment of Mississippian coastal lakes and marshes during the early terrestrialisation of tetrapods". Palaeogeography, Palaeoclimatology, Palaeoecology. 564: 110194. Bibcode:2021PPP...56410194B. doi:10.1016/j.palaeo.2020.110194. S2CID 233950487.
  36. ^ a b Clack, J. A. (2002). "An early tetrapod from 'Romer's Gap'". Nature. 418 (6893): 72–76. Bibcode:2002Natur.418...72C. doi:10.1038/nature00824. ISSN 1476-4687. PMID 12097908. S2CID 741732.
  37. ^ a b c Stephenson, Mike; Williams, Mark; Monaghan, Alison; Arkley, Sarah; Smith, Richard (2002). "Biostratigraphy and palaeoenvironments of the Ballagan Formation (lower Carboniferous) in Ayrshire". Scottish Journal of Geology. 38 (2): 93–111. doi:10.1144/sjg38020093. ISSN 0036-9276. S2CID 128538564.
  38. ^ a b c d e f g h Carpenter, David K.; Falcon-Lang, Howard J.; Benton, Michael J.; Henderson, Elsa (2014). López-Arbarello, Adriana (ed.). "Carboniferous (Tournaisian) fish assemblages from the Isle of Bute, Scotland: systematics and palaeoecology". Palaeontology. 57 (6): 1215–1240. doi:10.1111/pala.12112. S2CID 131648312.
  39. ^ Clayton, G. (1985). "Plant miospores from the Dinantian of Foulden, Berwickshire, Scotland". Earth and Environmental Science Transactions of the Royal Society of Edinburgh. 76 (1): 21–24. doi:10.1017/S0263593300010257. ISSN 1473-7116. S2CID 130886184.
  40. ^ a b Stephenson, M. H.; Williams, M.; Monghan, A. A.; Arkley, S.; Smith, R. A.; Dean, M.; Browne, M. A. E.; Leng, M. (2004). "Palynomorph and ostracod biostratigraphy of the Ballagan Formation, Midland Valley of Scotland, and elucidation of intra-Dinantian unconformaties". Proceedings of the Yorkshire Geological Society. 55 (2): 131–143. doi:10.1144/pygs.55.2.131. ISSN 0044-0604.
  41. ^ Stephenson, M. H.; Williams, M.; Leng, M.; Monghan, A. A. (2004). "Aquatic plant microfossils of probable non-vascular origin from the Ballagan Formation (Lower Carboniferous), Midland Valley, Scotland". Proceedings of the Yorkshire Geological Society. 55 (2): 145–158. doi:10.1144/pygs.55.2.145. ISSN 0044-0604.
  42. ^ Clack, J. A.; Finney, S. M. (1 January 2005). "Pederpes finneyae, an articulated tetrapod from the tournaisian of Western Scotland". Journal of Systematic Palaeontology. 2 (4): 311–346. doi:10.1017/S1477201904001506. ISSN 1477-2019. S2CID 86731604.
  43. ^ a b c Forey, P. L.; Young, V. T. (1985). "Acanthodian and coelacanth fish from the Dinantian of Foulden, Berwickshire, Scotland". Transactions of the Royal Society of Edinburgh: Earth Sciences. 76 (1): 53–59. doi:10.1017/S0263593300010300. ISSN 0263-5933. S2CID 130054980.
  44. ^ Størmer, Leif; Waterston, Charles D. (1968). "IV. Cyrtoctenus gen. nov., a large late Palaeozoic Arthropod with pectinate Appendages". Transactions of the Royal Society of Edinburgh. 68 (4): 63–104. doi:10.1017/S0080456800014563. ISSN 0080-4568. S2CID 131694288.
  45. ^ Taylor, Paul D.; Vinn, Olev (2006). "Convergent morphology in small spiral worm tubes (' Spirorbis ') and its palaeoenvironmental implications". Journal of the Geological Society. 163 (2): 225–228. Bibcode:2006JGSoc.163..225T. doi:10.1144/0016-764905-145. ISSN 0016-7649. S2CID 128971706.
  46. ^ Pollard, John E. (1985). "Coprolites and ostracods from the Dinantian of Foulden, Berwickshire, Scotland". Earth and Environmental Science Transactions of the Royal Society of Edinburgh. 76 (1): 49–51. doi:10.1017/S0263593300010294. ISSN 1473-7116. S2CID 130602159.
  47. ^ Williams, Mark; Stephenson, Michael; Wilkinson, Ian P.; Leng, Melanie J.; Miller, C. Giles (1 May 2005). "Early Carboniferous (Late Tournaisian–Early Viséan) ostracods from the Ballagan Formation, central Scotland, UK". Journal of Micropalaeontology. 24 (1): 77–94. doi:10.1144/jm.24.1.77. ISSN 0262-821X. S2CID 55470029.
  48. ^ Williams, Mark; Leng, Melanie J.; Stephenson, Michael H.; Andrews, Julian E.; Wilkinson, Ian P.; Siveter, David J.; Horne, David J.; Vannier, Jean M.C. (2006). "Evidence that Early Carboniferous ostracods colonised coastal flood plain brackish water environments". Palaeogeography, Palaeoclimatology, Palaeoecology. 230 (3–4): 299–318. Bibcode:2006PPP...230..299W. doi:10.1016/j.palaeo.2005.07.021.