Mathematics – Logic
Scientific paper
Aug 2006
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2006natur.442..908o&link_type=abstract
Nature, Volume 442, Issue 7105, pp. 908-911 (2006).
Mathematics
Logic
32
Scientific paper
The presence of mass-independently fractionated sulphur isotopes (MIF-S) in many sedimentary rocks older than ~2.4 billion years (Gyr), and the absence of MIF-S in younger rocks, has been considered the best evidence for a dramatic change from an anoxic to oxic atmosphere around 2.4Gyr ago. This is because the only mechanism known to produce MIF-S has been ultraviolet photolysis of volcanic sulphur dioxide gas in an oxygen-poor atmosphere. Here we report the absence of MIF-S throughout ~100-m sections of 2.76-Gyr-old lake sediments and 2.92-Gyr-old marine shales in the Pilbara Craton, Western Australia. We propose three possible interpretations of the MIF-S geologic record: (1) the level of atmospheric oxygen fluctuated greatly during the Archaean era; (2) the atmosphere has remained oxic since ~3.8Gyr ago, and MIF-S in sedimentary rocks represents times and regions of violent volcanic eruptions that ejected large volumes of sulphur dioxide into the stratosphere; or (3) MIF-S in rocks was mostly created by non-photochemical reactions during sediment diagenesis, and thus is not linked to atmospheric chemistry.
Ikemi Hiroaki
Ohmoto Hiroshi
Poulson Simon R.
Taylor Bruce E.
Watanabe Yumiko
No associations
LandOfFree
Sulphur isotope evidence for an oxic Archaean atmosphere does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Sulphur isotope evidence for an oxic Archaean atmosphere, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Sulphur isotope evidence for an oxic Archaean atmosphere will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1634253