1887
Volume 25, Issue 3
  • ISSN: 1354-0793
  • E-ISSN:
PDF

Abstract

Oil residues in Variscan granites in Cornwall, SW England, preserve biomarker data which indicate an origin from marine source rocks. The biomarkers also indicate a thermal maturity that excludes an origin from the Devono-Carboniferous rocks intruded by the granites, but is similar to that of Jurassic-sourced oil to the east in the Wessex Basin. A suite of five different samples from the South Crofty tin mine are variably biodegraded, implying alteration after emplacement of oil in the granite. These characteristics are compatible with models for updip flow of fluids from offshore Mesozoic sediments into older granite topographical highs.

[open-access]

Loading

Article metrics loading...

/content/journals/10.1144/petgeo2018-053
2018-12-19
2020-09-21
Loading full text...

Full text loading...

/deliver/fulltext/petgeo/25/3/petgeo2018-053.html?itemId=/content/journals/10.1144/petgeo2018-053&mimeType=html&fmt=ahah

References

  1. Alderton, D.H.M.
    1993. Mineralisation associated with the Cornubian Granite Batholith. In: Pattrick, R.E.D. & Polya, D.A. (eds) Mineralisation in the British Isles. Chapman & Hall, London, 270–354.
    [Google Scholar]
  2. Bath, A.H., Brassell, S.C. et al.
    1984. Deep Source Gases and Hydrocarbons in the U.K. Crust. Report of the Fluid Processes Research Group, British Geological Survey, FLPU 86-2.
    [Google Scholar]
  3. Boiron, M.C., Cathelineau, M. et al.
    2002. Fluid transfers at a basement/cover interface Part II. Large-scale introduction of chlorine into the basement by Mesozoic basinal brines. Chemical Geology, 192, 121–140.
    [Google Scholar]
  4. Bristow, C.M.
    1993. The genesis of the china clays of south-west England – a multistage story. In: Murray, H.H., Bundy, W.M. & Harvey, C.C. (eds) Kaolin Genesis and Utilization. The Clay Minerals Society, Boulder, 171–203.
    [Google Scholar]
  5. Burton, Z., Moldowan, J.M., Sykes, R. & Graham, S.
    2018. Unraveling petroleum degradation, maturity, and mixing and addressing impact on petroleum prospectivity; Insights from frontier exploration regions in New Zealand. Energy & Fuels, 32, 1287–1296, https://doi.org/10.1021/acs.energyfuels.7b03261
    [Google Scholar]
  6. Charoy, B.
    1986. The genesis of the Cornubian batholith (southwest England): the example of the Carnmenellis pluton. Journal of Petrology, 27, 571–604.
    [Google Scholar]
  7. Chen, Y., Clark, A.H., Farrar, E., Wasteneys, H.A., Hodgson, M.J. & Bromley, A.V.
    1993. Diachronous and independent histories of plutonism and mineralization in the Cornubian Batholith, southwest England. Journal of the Geological Society, London, 150, 1183–1191, https://doi.org/10.1144/gsjgs.150.6.1183
    [Google Scholar]
  8. Chen, Y., Zentilli, M.A., Clark, A.H., Farrar, E., Grist, A.M. & Willis-Richards, J.
    1996. Geochronological evidence for post-Variscan cooling and uplift of the Carnmenellis Granite, SW England. Journal of the Geological Society, London, 153, 191–195, https://doi.org/10.1144/gsjgs.153.2.0191
    [Google Scholar]
  9. Cope, J.C.W.
    2004. A new look at the post-Variscan evolution of south-west England. Geoscience in South-West England, 11, 1–9.
    [Google Scholar]
  10. Cornford, C., Yarnell, L. & Murchison, D.G.
    1987. Initial vitrinite reflectance results from the Carboniferous of north Devon and north Cornwall. Proceedings of the Ussher Society, 6, 461–467.
    [Google Scholar]
  11. Cornford, C., Jones, M. & Scrivener, R.C.
    2011. Towards an origin for Bideford Black. Geoscience in South-West England, 12, 356–363.
    [Google Scholar]
  12. Court, R.W., Sephton, M.A., Parnell, J. & Gilmour, I.
    2006. The alteration of organic matter in response to ionising irradiation: Chemical trends and implications for extraterrestrial sample analysis. Geochimica et Cosmochimica Acta, 70, 1020–1039.
    [Google Scholar]
  13. Dominy, S.C., Scrivener, R.C., Le Boutillier, N., Bussell, M.A. & Halls, C.
    1994. Crosscourses in South Crofty Mine, Cornwall: further studies of paragenesis and structure. Proceedings of the Ussher Society, 8, 237–241.
    [Google Scholar]
  14. Edmunds, W.M., Andrews, J.N., Burgess, W.G., Kay, R.L.F. & Lee, D.J.
    1984. The evolution of saline and thermal groundwaters in the Carnmenellis granite. Mineralogical Magazine, 48, 407–424.
    [Google Scholar]
  15. Edwards, R.A.
    1976. Tertiary sediments and structure of the Bovey Basin, south Devon. Proceedings of the Geologists’ Association, 87, 1–26.
    [Google Scholar]
  16. Evans, C.D.R.
    1990. United Kingdom Offshore Regional Report: The Geology of the Western English Channel and its Western Approaches. HMSO, London.
    [Google Scholar]
  17. Evans, C.D.R., Lott, G.K. & Warrington, G.
    1981. The Zephyr (1977) Wells, South-Western Approaches and Western English Channel. Institute of Geological Sciences Report, 81/8.
    [Google Scholar]
  18. Feely, M., Costanzo, A. et al.
    2017. Quartz-amethyst hosted hydrocarbon-bearing fluid inclusions from the green ridge breccia in the Snoqualmie granite, North Cascades, WA, USA. Minerals, 7, 174.
    [Google Scholar]
  19. Gleeson, S.A., Wilkinson, J.J., Shaw, H.F. & Herrington, R.J.
    2000. Post-magmatic hydrothermal circulation and the origin of base metal mineralization, Cornwall, UK. Journal of the Geological Society, London, 157, 589–600, https://doi.org/10.1144/jgs.157.3.589
    [Google Scholar]
  20. Haggerty, R., Budd, P., Rohl, B. & Gale, N.H.
    1996. Pb-isotope evidence for the role of Mesozoic basins in the genesis of Mississippi Valley-type mineralization in Somerset, UK. Journal of the Geological Society, London, 153, 673–676, https://doi.org/10.1144/gsjgs.153.5.0673
    [Google Scholar]
  21. Harrison, R.K. & Beer, K.E.
    1977. Elateritic hydrocarbon from South Crofty Mine, Cornwall: a preliminary note. Journal of Microscopy, 109, 165–169.
    [Google Scholar]
  22. Harrison, R.K. & Taylor, K.
    1966. Radian anglesite from Wheal Speed, Cornwall. Bulletin of the Geological Survey of Great Britain, 25, 41–48.
    [Google Scholar]
  23. Hawkes, J.R.
    1974. Volcanism and metallogenesis: the tin province of southwest England. Bulletin of Volcanology, 38, 1125–1146.
    [Google Scholar]
  24. Henwood, W.J.
    1843. On the metalliferous deposits of Cornwall and Devon. Transactions of the Royal Geological Society of Cornwall, 5, 1–386.
    [Google Scholar]
  25. Jackson, N.J., Willis-Richards, J., Manning, D.A.C. & Sams, M.
    1989. Evolution of the Cornubian orefield, southwest England. Part II. Mineral deposits and ore forming processes. Economic Geology, 84, 1101–1133.
    [Google Scholar]
  26. Klaproth, M.N.
    1787. Observations Relative to the Mineralogical and Chemical History of the Fossils of Cornwall. J. Johnson, London.
    [Google Scholar]
  27. Landais, P., Dubessy, J., Poty, B. & Robb, L.J.
    1990. Three examples illustrating the analysis of organic matter associated with uranium ores. Organic Geochemistry, 16, 601–608.
    [Google Scholar]
  28. LeBoutillier, N.G.
    1996. South Crofty Mine Geology & Mineralisation. Penhellick Publications, Camborne, UK.
    [Google Scholar]
  29. Macquaker, J.H.S., Farrimond, P. & Brassell, S.C.
    1986. Biological markers in the Rhaetian black shales of South West Britain. Organic Geochemistry, 10, 93–100.
    [Google Scholar]
  30. Moon, C.J.
    2010. Geochemical exploration in Cornwall and Devon: A review. Geochemistry: Exploration, Environment, Analysis, 10, 331–351, https://doi.org/10.1144/1467-7873/09-239
    [Google Scholar]
  31. Parfitt, M.A. & Farrimond, P.
    1998. The Mupe Bay oil seep: a detailed organic geochemical study of a controversial outcrop. In: Underhill, J. (ed.) Development, Evolution and Petroleum Geology of the Wessex Basin. Geological Society, London, Special Publications, 133, 387–397, https://doi.org/10.1144/GSL.SP.1998.133.01.20
    [Google Scholar]
  32. Parnell, J.
    1988. Migration of biogenic hydrocarbons into granites: a review of hydrocarbons in British plutons. Marine and Petroleum Geology, 5, 385–396.
    [Google Scholar]
  33. Parnell, J., Baba, M. & Bowden, S.
    2017a. Emplacement and biodegradation of oil in fractured basement: the ‘coal’ deposit in Moinian gneiss at Castle Leod, Ross-shire. Earth and Environmental Science Transactions of the Royal Society of Edinburgh, 107, 23–32.
    [Google Scholar]
  34. Parnell, J., Baba, M., Bowden, S. & Bullock, L.
    2017b. Geochemistry and origin of organic-rich sediment veins in fractured granitic basement, Helmsdale, Sutherlandshire, UK. Marine and Petroleum Geology, 88, 107–114.
    [Google Scholar]
  35. Parnell, J., Baba, M., Bowden, S. & Muirhead, D.
    2017c. Subsurface biodegradation of crude oil in a fractured basement reservoir, Shropshire, UK. Journal of the Geological Society, London, 174, 655–666, https://doi.org/10.1144/jgs2016-129
    [Google Scholar]
  36. Peters, K.E. & Moldowan, J.M.
    1993. The Biomarker Guide: Interpreting Molecular Fossils in Petroleum and Ancient Sediments. Prentice-Hall, Englewood Cliffs, NJ.
    [Google Scholar]
  37. Petford, N.
    & McCaffrey, K.J.W. (eds) 2003. Hydrocarbons in Crystalline Rocks. Geological Society, London, Special Publications, 214, https://doi.org/10.1144/GSL.SP.2003.214.01.14
    [Google Scholar]
  38. Powers, S.
    1932. Notes on minor occurrences of oil, gas and bitumen with igneous and metamorphic rocks. AAPG Bulletin, 16, 837–858.
    [Google Scholar]
  39. Psyrillos, A., Burley, S.D., Manning, D.A.C. & Fallick, A.E.
    2003. Coupled mineral-fluid evolution of a basin and high: kaolinization in the SW England granites in relation to the development of the Plymouth Basin. In: Petford, N. & McCaffrey, K.J.W. (eds) Hydrocarbons in Crystalline Rocks. Geological Society, London, Special Publications, 214, 175–195, https://doi.org/10.1144/GSL.SP.2003.214.01.11
    [Google Scholar]
  40. Rashleigh, P.
    1797. Specimens of British Minerals Selected from the Cabinet of Philip Rashleigh of Menabilly, in the County of Cornwall, with General Descriptions of Each Article. W. Bulmer & Co., London.
    [Google Scholar]
  41. Ruffell, A., Coward, M.P. & Harvey, M.
    1995. Geometry and tectonic evolution of megasequences in the Plymouth Bay Basin, English Channel. In: Boldy, S.A.R. (ed.) Permian and Triassic Rifting in Northwest Europe. Geological Society, London, Special Publications, 91, 193–214, https://doi.org/10.1144/GSL.SP.1995.091.01.10
    [Google Scholar]
  42. Sajgó, C.
    2000. Assessment of generation temperatures of crude oils. Organic Geochemistry, 31, 1301–1323.
    [Google Scholar]
  43. Scrivener, R.C., Darbyshire, D.P.F. & Shepherd, T.J.
    1994. Timing and significance of crosscourse mineralization in SW England. Journal of the Geological Society, London, 151, 587–590, https://doi.org/10.1144/gsjgs.151.4.0587
    [Google Scholar]
  44. Seifert, W.K. & Moldowan, J.M.
    1979. The effect of biodegradation on steranes and terpanes in crude oils. Geochimica et Cosmochimica Acta, 43, 111–126.
    [Google Scholar]
  45. Selley, R.C.
    1992. Petroleum seepages and impregnations in Great Britain. Marine and Petroleum Geology, 9, 226–244.
    [Google Scholar]
  46. Suan, G., Föllmi, K.B., Adatte, T., Bomou, B., Spangenberg, J.E. & Van de Schootbrugge, B.
    2012. Major environmental change and bonebed genesis prior to the Triassic–Jurassic mass extinction. Journal of the Geological Society, London, 169, 191–200, https://doi.org/10.1144/0016-76492011-045
    [Google Scholar]
  47. Trice, R.
    2014. Basement exploration, West of Shetlands: progress in opening a new play on the UKCS. In: Cannon, S.J.C. & Ellis, D. (eds) Hydrocarbon Exploration to Exploitation West of Shetlands. Geological Society, London, Special Publications, 397, 81–105, https://doi.org/10.1144/SP397.3
    [Google Scholar]
  48. Tweedy, W.M.
    1842. Notices of minerals of uncommon occurrence recently found in Cornwall. In: Twenty-Third Annual Report of the Royal Institution of Cornwall 1841. L.E. Gillet, Truro, UK, 38–39.
    [Google Scholar]
  49. Warrington, G. & Whittaker, A.
    1984. The Blue Anchor Formation (late Triassic) in Somerset. Proceedings of the Ussher Society, 6, 100–107.
    [Google Scholar]
  50. Webby, B.D.
    1965. The stratigraphy and structure of the Devonian rocks in the Quantock Hills, West Somerset. Proceedings of the Geologists’ Association, 76, 321–343.
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journals/10.1144/petgeo2018-053
Loading
/content/journals/10.1144/petgeo2018-053
Loading

Data & Media loading...

  • Article Type: Research Article
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error