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First record of the Hirnantian (Upper Ordovician) delta C-13 excursion in the North American Midcontinent and its regional implications

Bergstroem, Stig M.; Saltzman, Matthew M. and Schmitz, Birger LU (2006) In Geological Magazine 143(5). p.657-678
Abstract
The most prominent of the two major global delta C-13 excursions in the Ordovician, the Hirnantian delta C-13 excursion (HICE), which is previously recorded from the uppermost Ordovician in a few sections in Nevada, Quebec, Arctic Canada, Baltoscandia, Scotland and China, is documented for the first time from the North American Midcontinent. Samples through the Girardeau Limestone and Leemon Formation in Missouri and Illinois show elevated delta C-13 values of + 4 parts per thousand to + 5 parts per thousand. Although not determined precisely, the beginning of the HICE is likely to be in the upper part of the Orchard Creek Shale, and it ends in the upper Leemon Formation. Being extraordinarily useful chronostratigraphically, the presence... (More)
The most prominent of the two major global delta C-13 excursions in the Ordovician, the Hirnantian delta C-13 excursion (HICE), which is previously recorded from the uppermost Ordovician in a few sections in Nevada, Quebec, Arctic Canada, Baltoscandia, Scotland and China, is documented for the first time from the North American Midcontinent. Samples through the Girardeau Limestone and Leemon Formation in Missouri and Illinois show elevated delta C-13 values of + 4 parts per thousand to + 5 parts per thousand. Although not determined precisely, the beginning of the HICE is likely to be in the upper part of the Orchard Creek Shale, and it ends in the upper Leemon Formation. Being extraordinarily useful chronostratigraphically, the presence of the HICE makes it possible to provide a firm dating of the study interval, whose age has long been controversial. Comparison between the study sections and coeval HICE sequences in North America and Europe show striking similarities, especially in sea-level history, indicating that major local lowstands reflect eustatic sea-level changes. A comparison with Hirnantian diamictite successions in North and South Africa and Argentina suggests that these lowstands correspond to two major Gondwanan glacial episodes. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
sea-level changes, glaciation, Gondwana, Missouri-Illinois, Upper Ordovician, carbon isotope excursion, Hirnantian
in
Geological Magazine
volume
143
issue
5
pages
657 - 678
publisher
Cambridge University Press
external identifiers
  • wos:000241142600005
  • scopus:33748313029
ISSN
0016-7568
DOI
10.1017/S0016756806002469
language
English
LU publication?
yes
id
6bdb49da-fea7-4057-9338-2947e79f59cc (old id 388440)
date added to LUP
2007-08-27 13:13:39
date last changed
2019-02-20 03:59:37
@article{6bdb49da-fea7-4057-9338-2947e79f59cc,
  abstract     = {The most prominent of the two major global delta C-13 excursions in the Ordovician, the Hirnantian delta C-13 excursion (HICE), which is previously recorded from the uppermost Ordovician in a few sections in Nevada, Quebec, Arctic Canada, Baltoscandia, Scotland and China, is documented for the first time from the North American Midcontinent. Samples through the Girardeau Limestone and Leemon Formation in Missouri and Illinois show elevated delta C-13 values of + 4 parts per thousand to + 5 parts per thousand. Although not determined precisely, the beginning of the HICE is likely to be in the upper part of the Orchard Creek Shale, and it ends in the upper Leemon Formation. Being extraordinarily useful chronostratigraphically, the presence of the HICE makes it possible to provide a firm dating of the study interval, whose age has long been controversial. Comparison between the study sections and coeval HICE sequences in North America and Europe show striking similarities, especially in sea-level history, indicating that major local lowstands reflect eustatic sea-level changes. A comparison with Hirnantian diamictite successions in North and South Africa and Argentina suggests that these lowstands correspond to two major Gondwanan glacial episodes.},
  author       = {Bergstroem, Stig M. and Saltzman, Matthew M. and Schmitz, Birger},
  issn         = {0016-7568},
  keyword      = {sea-level changes,glaciation,Gondwana,Missouri-Illinois,Upper Ordovician,carbon isotope excursion,Hirnantian},
  language     = {eng},
  number       = {5},
  pages        = {657--678},
  publisher    = {Cambridge University Press},
  series       = {Geological Magazine},
  title        = {First record of the Hirnantian (Upper Ordovician) delta C-13 excursion in the North American Midcontinent and its regional implications},
  url          = {http://dx.doi.org/10.1017/S0016756806002469},
  volume       = {143},
  year         = {2006},
}