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The preservation of fossil biomarkers during meteorite impact events : Experimental evidence from biomarker-rich projectiles and target rocks

Parnell, John; Bowden, Stephen; Lindgren, Paula LU ; Burchell, Mark; Milner, Daniel; Price, Mark; Baldwin, Emily C. and Crawford, Ian A. (2010) In Meteoritics and Planetary Science 45(8). p.1340-1358
Abstract

A Devonian siltstone from Orkney, Scotland, shows survival of biomarkers in high-velocity impact experiments. The biomarkers were detected in ejecta fragments from experiments involving normal incidence of steel projectiles at 5-6 km s-1, and in projectile fragments from impact experiments into sand and water at 2-5 km s-1. The associated peak shock pressures were calculated to be in the range of 110-147 GPa for impacts of the steel projectiles into the siltstone target, and hydrocode simulations are used to show the variation of peak pressure with depth in the target and throughout the finite volume projectiles. Thermally sensitive biomarker ratios, including ratios of hopanoids and steranes, and the... (More)

A Devonian siltstone from Orkney, Scotland, shows survival of biomarkers in high-velocity impact experiments. The biomarkers were detected in ejecta fragments from experiments involving normal incidence of steel projectiles at 5-6 km s-1, and in projectile fragments from impact experiments into sand and water at 2-5 km s-1. The associated peak shock pressures were calculated to be in the range of 110-147 GPa for impacts of the steel projectiles into the siltstone target, and hydrocode simulations are used to show the variation of peak pressure with depth in the target and throughout the finite volume projectiles. Thermally sensitive biomarker ratios, including ratios of hopanoids and steranes, and the methylphenanthrene ratio, showed an increase in thermal maturity in the ejecta, and especially the projectile, fragments. Measurement of absolute concentrations of selected biomarkers indicates that changes in biomarker ratios reflect synthesis of new material rather than selective destruction. Their presence in ejecta and projectile fragments suggests that fossil biomarkers may survive hypervelocity impacts, and that experiments using biomarker-rich rock have high potential for testing survival of organic matter in a range of impact scenarios.

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author
publishing date
type
Contribution to journal
publication status
published
subject
in
Meteoritics and Planetary Science
volume
45
issue
8
pages
19 pages
publisher
Wiley-Blackwell
external identifiers
  • scopus:78649571346
ISSN
1086-9379
DOI
10.1111/j.1945-5100.2010.01100.x
language
English
LU publication?
no
id
d9638ce0-0bb7-4729-b5ce-d6cb4646d3da
date added to LUP
2017-06-26 09:59:26
date last changed
2018-05-29 11:44:47
@article{d9638ce0-0bb7-4729-b5ce-d6cb4646d3da,
  abstract     = {<p>A Devonian siltstone from Orkney, Scotland, shows survival of biomarkers in high-velocity impact experiments. The biomarkers were detected in ejecta fragments from experiments involving normal incidence of steel projectiles at 5-6 km s<sup>-1</sup>, and in projectile fragments from impact experiments into sand and water at 2-5 km s<sup>-1</sup>. The associated peak shock pressures were calculated to be in the range of 110-147 GPa for impacts of the steel projectiles into the siltstone target, and hydrocode simulations are used to show the variation of peak pressure with depth in the target and throughout the finite volume projectiles. Thermally sensitive biomarker ratios, including ratios of hopanoids and steranes, and the methylphenanthrene ratio, showed an increase in thermal maturity in the ejecta, and especially the projectile, fragments. Measurement of absolute concentrations of selected biomarkers indicates that changes in biomarker ratios reflect synthesis of new material rather than selective destruction. Their presence in ejecta and projectile fragments suggests that fossil biomarkers may survive hypervelocity impacts, and that experiments using biomarker-rich rock have high potential for testing survival of organic matter in a range of impact scenarios.</p>},
  author       = {Parnell, John and Bowden, Stephen and Lindgren, Paula and Burchell, Mark and Milner, Daniel and Price, Mark and Baldwin, Emily C. and Crawford, Ian A.},
  issn         = {1086-9379},
  language     = {eng},
  number       = {8},
  pages        = {1340--1358},
  publisher    = {Wiley-Blackwell},
  series       = {Meteoritics and Planetary Science},
  title        = {The preservation of fossil biomarkers during meteorite impact events : Experimental evidence from biomarker-rich projectiles and target rocks},
  url          = {http://dx.doi.org/10.1111/j.1945-5100.2010.01100.x},
  volume       = {45},
  year         = {2010},
}