Impacts and Wildfires - An Analysis of the K-T Event

  • C. M. Belcher
Part of the Impact Studies book series (IMPACTSTUD)


Models of the Cretaceous-Tertiary (K-T) impact at Chicxulub have suggested that thermal radiation would have been sufficient to have ignited extensive or near global wildfires. The discovery of abundant soot, increased levels of polyaromatic hydrocarbons (PAHs), and the possible occurrences of the fullerenes C60 and C70 have been considered to support the wildfire hypothesis. However, the charcoal record from K-T sites stretching the length of the Western Interior of the USA reveals amounts of charcoal below background levels and an abundance of non-charred material in the K-T and earliest Tertiary rocks.

Explanations to account for this disagreement between the charcoal record and the other potential wildfire indicators include: charcoal formation but subsequent oxidation (by acid rains or during diagenesis), and intense thermal radiation converting charcoal directly to CO2. In both scenarios significant quantities of non-charred material would not be expected to survive. There is no satisfactory hypothesis to explain how charcoal could be transported away from the entire Western Interior, and it is unlikely that conditions prevailed in the Western Interior that prevented the fires.

Following re-analysis of the proposed wildfire evidence, the abundance of soot, PAHs, and fullerenes can be explained without invoking the global wildfire hypothesis. It has been concluded that fullerenes are not a suitable indicator for impact-related palaeo-wildfires. The morphology of the K-T soot is characteristic of soots produced during combustion of hydrocarbons. The uniformity of its carbon isotope signature between sites across the globe is better explained by the vaporisation of one pool of hydrocarbons. The PAH record of the K-T rocks includes compounds that are never formed from the burning of biomass but that are released during the combustion of hydrocarbons. Recent Chicxulub drill cores reveal that the target rocks contain hydrocarbons, the vaporisation of which could produce the soot and PAHs found at the K-T boundary.


Biomass Burning Polyaromatic Hydrocarbon Charcoal Record Target Rock Chicxulub Impact 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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  1. Alvarez LW, Alvarez W, Asaro F, Michel HV (1980) Extraterrestrial cause for the Cretaceous-Tertiary extinction. Science 208: 1095–1108Google Scholar
  2. Arinbou T, Ishiwatari R, Kaiho K, Lamolda MA (1999) Spike of pyrosynthetic polycyclic aromatic hydrocarbons associated with an abrupt decrease in δ13C of a terrestrial biomarker at the Cretaceous-Tertiary boundary at Caravaca Spain. Geology 27: 723–726CrossRefGoogle Scholar
  3. Becker L, Bada J, Bunch TE (1995) Fullerenes in the K-T boundary: Are they a result of global fires [abs]. Lunar and Planetary Science 26: 85–86Google Scholar
  4. Becker L, Poreda RJ, Bunch TE (2000) Fullerenes: An extraterrestrial carbon carrier phase for noble gases. Proceedings of the National Academy of Sciences of the USA 97: 2979–2983CrossRefGoogle Scholar
  5. Belcher CM, Collinson ME, Sweet AR, Hildebrand AR, Scott AC (2003) “Fireball passes and nothing burns”-The role of thermal radiation in the K-T event: Evidence from the charcoal record of North America. Geology 31: 1061–1064CrossRefGoogle Scholar
  6. Belcher CM, Collinson ME, Sweet AR, Hildebrand AR, Scott AC (2005) Constraints on the thermal energy released from the Chixculub impactor: new evidence from multi-method charcoal analysis. Journal of the Geological Society of London, 162: 591–602CrossRefGoogle Scholar
  7. Berner RA, Lasaga AC, Garrels RM (1983) The carbonate-silicate geochemical cycle and its effect on atmospheric carbon dioxide over the past 100 million years. American Journal of Science 283: 641–683CrossRefGoogle Scholar
  8. Blumer M (1975) Curtisite, Irdrialite and pendletonite, polyaromatic hydrocarbon minerals: their composition and origin. Chemical Geology 16: 245–256CrossRefGoogle Scholar
  9. Broecker WS, Peng TH (1982) Tracers in the Sea. Eldigo, New York, 690 ppGoogle Scholar
  10. Ehrenfreund P, Foing BH (1995) Search for fullerenes and PAHs in diffuse interstellar medium. Planetary and Space Science 43: 1183–1187CrossRefGoogle Scholar
  11. Fernandes MB, Skjemstad JO, Johnson BB, Wells JD, Brooks P (2003) Characterization of carbonaceous combustion residues. I. Morphological, elemental and spectroscopic features. Chemosphere 51: 785–795CrossRefGoogle Scholar
  12. Gerstl SA, Zaerdecki A (1982) Reduction of photosynthetically active radiation under extreme stratospheric aerosol loads. In: Silver LT, Schultz PH (eds) Geological implications of impacts of large asteroids and comets on Earth. Geological Society of America Special Paper 247: 367–382Google Scholar
  13. Gilmour I, Guenther F (1988) The global Cretaceous-Tertiary fire: biomass or fossil carbon? [abs.]. In: Global Catastrophes in Earth History, Lunar and Planetary Institute Contribution 673: 60–61Google Scholar
  14. Gilmour I, Wolbach WS, Anders E (1990) Major wildfires at the Cretaceous-Tertiary boundary. In: Clube SVM (eds) Catastrophes and Evolution: Astronomical Foundations, Cambridge University Press, Cambridge, pp 195–213Google Scholar
  15. Gilmour I, Sephton MA, Morgan JV (2003) Organic geochemistry of a hydrocarbon-rich calcarenite from the Chicxulub scientific drilling program [abs.]. Lunar and Planetary Science XXXIV [abs.] #1771 (CD-ROM)Google Scholar
  16. Heymann D, Chibante LPF, Brooks RR, Wolbach WS, Smalley RE (1994) Fullerenes in the Cretaceous-Tertiary boundary layer. Science 265: 645–647Google Scholar
  17. Heymann D, Chibante LPF, Brooks RR, Wolbach WS, Smit J, Korochantsev A, Nazarov MA, Smalley RE (1996) Fullerenes of possible wildfire origin in Cretaceous-Tertiary boundary sediments. In: Ryder G, Fastovsky D, Gartner S (eds) The Cretaceous-Tertiary event and other catastophes in earth history. Geological Sociecty of America Special Paper 307: 453–464Google Scholar
  18. Heymann D, Yancey TE, Wolbach WS, Thiemens MH, Johnson EA, Roach D, Moecker S (1998) Geochemical markers of the Cretaceous-Tertiary boundary event at Brazos River, Texas, USA. Geochimica et Cosmochimica Acta 62: 173–181CrossRefGoogle Scholar
  19. Hildebrand AR (1993) The Cretaceous/Tertiary boundary impact (or the dinosaurs didn’t have a chance). Journal of the Royal Astronomical Society of Canada 87: 77–118Google Scholar
  20. Hildebrand AR, Boynton WV (1989) Hg anomalies at the K/T boundary-evidence for acid rain [abs.] Meteoritics 24: 277–278Google Scholar
  21. Hildebrand AR, Wolbach WS (1989) Carbon and chalcophiles at a non marine K/T boundary: Joint investigations of the Raton section, New Mexico [abs.] Lunar and Planetary Science 20: 414–415Google Scholar
  22. Hildebrand AR, Penfield GT, Kring DA, Pilkington M, Camargo A, Jacobsen SB, Boynton WV (1991) Chicxulub crater: A possible Cretaceous-Tertiary boundary impact crater on the Yucatán Peninsula, Mexico. Geology 19: 867–871CrossRefGoogle Scholar
  23. Innes JB, Simmons IG (2000) Mid Holocene charcoal stratigraphy, fire history and palaeoecology at North Gill, North York Moors, UK. Palaeogeography, Palaeoclimatology, Palaeoecology 164: 151–166CrossRefGoogle Scholar
  24. Izett GA (1990) The Cretaceous/Tertiary boundary interval, Raton Basin, Colorado and New Mexico, and its content of shock-metamorphosed minerals: Evidence relevant to the K/T boundary impact-extinction theory. Geological Society of America Special Paper 249: 100 ppGoogle Scholar
  25. Jones TP (1996) Comment on “Fossil charcoal in Cretaceous-Tertiary boundary strata: evidence for catastrophic firestorm and megawave”. Geochimica et Cosmochimica Acta 60: 719–720CrossRefGoogle Scholar
  26. Jones TP, Lim B (2000) Extra terrestrial impacts and wildfires. Palaeogeography, Palaeoclimatology, Palaeoecology 164: 57–66CrossRefGoogle Scholar
  27. Killops SD, Killops VJ (1993) An Introduction to Organic Geochemistry. Geochemistry Series, Longman Scientific and Technical, John Wiley and Sons, New York, 265 ppGoogle Scholar
  28. Kring DA, Durda, DD (2002) Trajectories and distribution of material ejected from the Chicxulub impact crater: Implications for post impact wildfires. Journal of Geophysical Research 107: 6–22 DOI:10.1029/2001JE001532Google Scholar
  29. Kruge MA, Stankiewicz BA, Creilling JC, Montanari A, Bensley DF (1994) Fossil charcoal in Cretaceous-Tertiary boundary strata: evidence for catastrophic firestorm and megawave. Geochimica et Cosmochimica Acta 58: 1393–1397CrossRefGoogle Scholar
  30. Kruge MA, Stankiewicz BA, Creilling JC, Montanari A, Bensley DF (1996) Reply to the Comment by TP Jones on “Fossil charcoal in Cretaceous-Tertiary boundary strata: evidence for catastrophic firestorm and megawave”. Geochimica et Cosmochimica Acta 60: 721–722CrossRefGoogle Scholar
  31. MacLeod N, and 21 others (1996) The Cretaceous-Tertiary biotic transition. Journal of the Geological Society, London 153: 1–28Google Scholar
  32. Melosh HJ, Schneider NM, Zahnle KJ, Latham D (1990) Ignition of global wildfires at the Cretaceous/Tertiary boundary. Nature 343: 251–254CrossRefGoogle Scholar
  33. Masclet A, Liousse C, Wortham H (1995) Emissions of polycyclic hydrocarbons by savanna fires. Journal of Atmospheric Chemistry 22: 41–54CrossRefGoogle Scholar
  34. Nichols DJ, Johnson KR (2002) Palynology and microstratigraphy of Cretaceous-Tertiary boundary sections in southwestern North Dakota. In: Hartman JH, Johnson KR, Nichols DJ (eds) The Hell Creek Formation of the Cretaceous-Tertiary boundary in the northern great plains. Geological Society of America Special Paper 361, pp 95–143Google Scholar
  35. O’Keefe JD, Ahrens TJ (1989) Impact production of CO2 by the Cretaceous-Tertiary extinction bolide and the resultant heating of the Earth. Nature 338: 247–249CrossRefGoogle Scholar
  36. Oros DR, Simoneit BRT (2000) Identification and emission rates of molecular tracers in coal smoke particulate matter. Fuel 79: 515–536CrossRefGoogle Scholar
  37. Oros DR, Simoneit BRT (2001a) Identification and emission factors of molecular tracers in organic aerosols from biomass burning. Part 1. Temperate climate conifers. Applied Geochemistry 16: 1513–1544CrossRefGoogle Scholar
  38. Oros DR, Simoneit BRT (2001b) Identification and emission factors of molecular tracers in organic aerosols from biomass burning. Part 2. Decidous trees. Applied Geochemistry 16: 1545–1565CrossRefGoogle Scholar
  39. Page SE, Siegert F, Rieley JO., Boehm HDV, Jaya A, Limin S (2002) The amount of carbon released from peat and forest fires in Indonesia during 1997. Nature 420: 61–65CrossRefGoogle Scholar
  40. Patterson III, WA, Edwards KJ, Maguire DJ (1987) Microscopic charcoal as a fossil indicator of fire. Quaternary Science Reviews 6: 3–23CrossRefGoogle Scholar
  41. Pillmore CL, Flores RM (1990) Stratigraphy and depositional environments of the Cretaceous-Tertiary boundary clay and associated rocks, Raton basin, New Mexico and Colorado. In: Fassett JE, Rigby JK (eds) The Cretaceous-Tertiary boundary in the San Juan and Raton Basins, New Mexico and Colorado. Geological Society of America Special Paper 209: 111–129Google Scholar
  42. Piperno DR (1997) Proceedings of the Ocean Drilling Program, Scientific Results, Vol. 155: College Station, Texas, Ocean Drilling Program, pp 411–418Google Scholar
  43. Pope KO (2002) Impact dust not the cause of the Cretaceous-Tertiary mass extinction. Geology 30: 99–102CrossRefGoogle Scholar
  44. Ramdahl T (1983) Retene a molecular marker of wood combustion in ambient air. Nature 306: 580–582CrossRefGoogle Scholar
  45. Scott AC, Lomax B, Collinson ME, Upchurch G, Beerling D (2000) Fire across the K-T boundary: Initial results from the Sugarite coal, New Mexico, USA. Palaeogeography, Palaeoclimatology, Palaeoecology 164: 381–395CrossRefGoogle Scholar
  46. Shuvalov VV, Artemieva NA (2002) Atmospheric erosion and radiation impulse induced by impacts. In: Koeberl C, MacLeod KG (eds) Catastrophic events and mass extinctions: Impacts and beyond. Geological Society of America Special Paper 356: 695–703Google Scholar
  47. Simoneit BRT (2002) Biomass burning-a review of organic tracers for smoke from incomplete combustion. Applied Geochemistry 17: 129–162CrossRefGoogle Scholar
  48. Stoffyn-Egli P, Potter TM, Leonard JD, Pocklington R (1997) The identification of black carbon particles with the analytical scanning electron microscope: methods and initial results. The Science of the Total Environment 198: 211–223CrossRefGoogle Scholar
  49. Sweet AR (2001) Plants, a yardstick for measuring the environmental consequences of the Cretaceous-Tertiary boundary event. Geoscience Canada 28:127–138Google Scholar
  50. Sweet AR, Cameron AR (1991) Palynofacies, coal petrographic facies and depositional environments: Amphitheatre Fornation (Eocene to Oligocene) and Ravenscrag Formation (Maastrichtian to Paleocene). Canada International Journal of Coal Geology 19: 121–144CrossRefGoogle Scholar
  51. Sweet AR, Braman DR, Lerbekmo JF (1999) Sequential palynological changes across the composite Cretaceous-Tertiary (K-T) boundary claystone and contiguous strata, western Canada and Montana, USA. Canadian Journal of Earth Sciences 36: 743–768CrossRefGoogle Scholar
  52. Taylor R (1999) Lecture Notes on Fullerene Chemistry-a Handbook for Chemists, Imperial College Press, London, 268 ppGoogle Scholar
  53. Taylor R, Abdul-Sada AK (2000) There are no fullerenes in the K-T boundary layer. Fullerene Science and Technology 8: 47–54Google Scholar
  54. Toon OB, Pollack JB, Ackerman TP, Turco RP, McKay CP, Liu MS (1982) Evolution of an impact generated dust cloud and its effects on the atmosphere. In: Silver LT, Schultz PH (eds) Geological implications of impacts of large asteroids and comets on the Earth. Geological Society of America Special Paper 190: 187–201Google Scholar
  55. Tschudy RH, Pillmore CL, Orth CJ, Gillmore JS, Knight JD (1984) Disruption of the terrestrial plant ecosystem at the Cretaceous-Tertiary boundary, Western Interior. Science 225: 1030–1032Google Scholar
  56. Venkatesan MI, Dahl J (1989) Further geochemical evidence for global fires at the Cretaceous-Tertiary boundary. Nature 338: 57–60CrossRefGoogle Scholar
  57. Wolbach WS, Lewis RS, Anders E (1985) Cretaceous extinctions: Evidence for wildfires and search for meteoritic material. Science 230: 167–230Google Scholar
  58. Wolbach WS, Gilmour I, Anders E, Orth CJ, Brooks RR (1988) Global fire at the Cretaceous-Tertiary boundary. Nature 334: 665–669CrossRefGoogle Scholar
  59. Wolbach WS, Gilmour I, Anders E (1990) Major wildfires at the Cretaceous/Tertiary boundary. In: Sharpton VL, Ward PD (eds) Global catastrophes in Earth history. Geological Society of America Special Paper 247: 391–400Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • C. M. Belcher
    • 1
  1. 1.Department of GeologyRoyal Holloway University of LondonEgham, SurreyUK

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