Steptoean positive carbon isotope excursion: Difference between revisions

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added # of localities for each country. Gives a better idea of global distribution.
Beitz 48 (talk | contribs)
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Added intro paragraph and map with localities. Attempted to add a recreated map showing localities as they would appear during Cambrian but map was consistently blocked due to Wikipedia's copyright rules.
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The '''Steptoean Positive Carbon Isotope Excursion (SPICE)''' is a global [[Chemostratigraphy|chemostratigraphic]] event which occurred in the upper [[Cambrian]] period , corresponding with the [[International Commission on Stratigraphy|ICS]] [[Guzhangian]]- [[Paibian]] stage boundary (as well as the [[Miaolingian]]- [[Furongian]] series boundary and North American Marjuman- Streptoean stage boundary). <ref name=":18" /> This event is characterized by a globally corelated positive excursion of [[Δ13C|δ<sup>13</sup>C]] values in stratigraphy between 497 and 494 million years ago. During this 3 million year period δ<sup>13</sup>C values increased to maximum values of 4 to 6 ‰ ([[per mille]]). The onset of SPICE also corresponds with the End-Marjuman Biomere Extinction. An event which saw significant extinction and turnover in global trilobite and brachiopod species. <ref name=":19" />
The '''Steptoean Positive Carbon Isotope Excursion (SPICE)''' was a geological event which occurred about 495 million years ago near the beginning of the International [[Furongian]] Epoch of the [[Cambrian]] Period. The SPICE represents an increase in the atmospheric [[Carbon-13|<sup>13</sup>C]] to [[Carbon-12|<sup>12</sup>C]] ratio, known as the [[Δ13C|δ<sup>13</sup>C]], and lasted for around 2 to 4 million years.

⚫
=== Localities and Geology ===
[[File:Blank-World-Map.jpg|alt=Map of the world with various countries highlighted in red. Countries include: United States of America, China, Australia, Argentina, Newfoundland (Canada), Korea, France, Kazakhstan, Scotland, and Siberia (Russia)|thumb|400x400px|Modern countries and regions with formations containing the SPICE excursion (highlighted in red). Base world map sourced from GIS Geography (2024). ]]








⚫
A rise in the atmospheric δ<sup>13</sup>C ratio doesn't necessarily infer a rise in abolute atmospheric carbon concentration. An increase of δ<sup>13</sup>C such as during SPICE is rather interpreted as the result of increased carbon fixation primarily by plants, which fix <sup>12</sup>C more readily than <sup>13</sup>C, and the subsequent burial of this organic carbon in sedimentary rocks. This removal of atmospheric <sup>12</sup>C in higher proportion than <sup>13</sup>C signifies increased proliferation of life and shifts the ratio towards <sup>13</sup>C. This shift during SPICE is interpreted to be a global disturbance in the [[carbon cycle]], affecting the atmosphere and the oceans in equal proportion as described by [[Henry's law]]. Regional sea level changes, a rise in sea water temperatures, ocean anoxia, and [[trilobite]] and [[brachiopod]] extinctions are associated with the SPICE event, although the exact mechanisms causing these events are still unconfirmed.


⚫
One proposed cause of the SPICE is an increase in the burial of organic carbon, perhaps caused by increased primary productivity (e.g. [[photosynthesis]]) or enhanced organic matter preservation due to ocean deoxygenation (i.e. [[Anoxic event|anoxia]] or [[euxinia]]). The spread of seafloor anoxia, facilitated by higher ocean temperatures, has also been proposed as the kill mechanism for the extinctions of marine organisms.


⚫
=== Localities and Geology ===
{| class="wikitable"
{| class="wikitable"
|+'''All Localities SPICE Has Been Observed'''
|+
!Modern Country
!Modern Country
!Paleocontinent
!Paleocontinent
Line 47: Line 53:
(8 localities)
(8 localities)
|Gondwana
|Gondwana
|'''North China:
|'''North China:'''
*Changshan Formation, Tangwangzhai section, Gushan, Shangdong Province <ref name=":7">{{Cite journal |last=Saltzman |first=Matthew R. |last2=Ripperdan |first2=Robert L. |last3=Brasier |first3=M.D. |last4=Lohmann |first4=Kyger C. |last5=Robison |first5=Richard A. |last6=Chang |first6=W.T. |last7=Peng |first7=Shanchi |last8=Ergaliev |first8=E.K. |last9=Runnegar |first9=Bruce |date=2000-10-01 |title=A global carbon isotope excursion (SPICE) during the Late Cambrian: relation to trilobite extinctions, organic-matter burial and sea level |url=https://linkinghub.elsevier.com/retrieve/pii/S0031018200001280 |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |language=en |volume=162 |issue=3-4 |pages=211–223 |doi=10.1016/S0031-0182(00)00128-0}}</ref>
*Changshan Formation, Tangwangzhai section, Gushan, Shangdong Province <ref name=":7">{{Cite journal |last=Saltzman |first=Matthew R. |last2=Ripperdan |first2=Robert L. |last3=Brasier |first3=M.D. |last4=Lohmann |first4=Kyger C. |last5=Robison |first5=Richard A. |last6=Chang |first6=W.T. |last7=Peng |first7=Shanchi |last8=Ergaliev |first8=E.K. |last9=Runnegar |first9=Bruce |date=2000-10-01 |title=A global carbon isotope excursion (SPICE) during the Late Cambrian: relation to trilobite extinctions, organic-matter burial and sea level |url=https://linkinghub.elsevier.com/retrieve/pii/S0031018200001280 |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |language=en |volume=162 |issue=3-4 |pages=211–223 |doi=10.1016/S0031-0182(00)00128-0}}</ref>
*Chaomidian Formation, Shandong Province <ref name=":8">{{Cite journal |last=Chen |first=Jitao |last2=Chough |first2=S.K. |last3=Han |first3=Zuozhen |last4=Lee |first4=Jeong-Hyun |date=2011-01-01 |title=An extensive erosion surface of a strongly deformed limestone bed in the Gushan and Chaomidian formations (late Middle Cambrian to Furongian), Shandong Province, China: Sequence–stratigraphic implications |url=https://linkinghub.elsevier.com/retrieve/pii/S0037073810003179 |journal=Sedimentary Geology |language=en |volume=233 |issue=1-4 |pages=129–149 |doi=10.1016/j.sedgeo.2010.11.002}}</ref><ref name=":9">{{Cite journal |last=Wang |first=Zhaopeng |last2=Chen |first2=Jitao |last3=Liang |first3=Taitao |last4=Yuan |first4=Jinliang |last5=Han |first5=Chao |last6=Liu |first6=Jiaye |last7=Zhu |first7=Chenlin |last8=Zhu |first8=Decheng |last9=Han |first9=Zuozhen |date=2020-05-15 |title=Spatial variation in carbonate carbon isotopes during the Cambrian SPICE event across the eastern North China Platform |url=https://linkinghub.elsevier.com/retrieve/pii/S0031018220301140 |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |language=en |volume=546 |pages=109669 |doi=10.1016/j.palaeo.2020.109669}}</ref>
*Chaomidian Formation, Shandong Province <ref name=":8">{{Cite journal |last=Chen |first=Jitao |last2=Chough |first2=S.K. |last3=Han |first3=Zuozhen |last4=Lee |first4=Jeong-Hyun |date=2011-01-01 |title=An extensive erosion surface of a strongly deformed limestone bed in the Gushan and Chaomidian formations (late Middle Cambrian to Furongian), Shandong Province, China: Sequence–stratigraphic implications |url=https://linkinghub.elsevier.com/retrieve/pii/S0037073810003179 |journal=Sedimentary Geology |language=en |volume=233 |issue=1-4 |pages=129–149 |doi=10.1016/j.sedgeo.2010.11.002}}</ref><ref name=":9">{{Cite journal |last=Wang |first=Zhaopeng |last2=Chen |first2=Jitao |last3=Liang |first3=Taitao |last4=Yuan |first4=Jinliang |last5=Han |first5=Chao |last6=Liu |first6=Jiaye |last7=Zhu |first7=Chenlin |last8=Zhu |first8=Decheng |last9=Han |first9=Zuozhen |date=2020-05-15 |title=Spatial variation in carbonate carbon isotopes during the Cambrian SPICE event across the eastern North China Platform |url=https://linkinghub.elsevier.com/retrieve/pii/S0031018220301140 |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |language=en |volume=546 |pages=109669 |doi=10.1016/j.palaeo.2020.109669}}</ref>
*Gushan Formation <ref name=":8" /><ref name=":9" />
*Gushan Formation <ref name=":8" /><ref name=":9" />
*Huangyangshan (HYS) section, Shandong Province <ref name=":10">{{Cite journal |last=Zuo |first=Jingxun |last2=Peng |first2=Shanchi |last3=Qi |first3=Yuping |last4=Zhu |first4=Xuejian |last5=Bagnoli |first5=Gabriella |last6=Fang |first6=Huaibin |date=2018-06-01 |title=Carbon-Isotope Excursions Recorded in the Cambrian System, South China: Implications for Mass Extinctions and Sea-Level Fluctuations |url=http://link.springer.com/10.1007/s12583-017-0963-x |journal=Journal of Earth Science |language=en |volume=29 |issue=3 |pages=479–491 |doi=10.1007/s12583-017-0963-x |issn=1674-487X}}</ref><ref name=":11">{{Cite journal |last=Li |first=Dandan |last2=Zhang |first2=Xiaolin |last3=Hu |first3=Dongping |last4=Chen |first4=Xiaoyan |last5=Huang |first5=Wei |last6=Zhang |first6=Xu |last7=Li |first7=Menghan |last8=Qin |first8=Liping |last9=Peng |first9=Shanchi |last10=Shen |first10=Yanan |date=2018-07-01 |title=Evidence of a large δ13Ccarb and δ13Corg depth gradient for deep-water anoxia during the late Cambrian SPICE event |url=https://pubs.geoscienceworld.org/gsa/geology/article/46/7/631/532092/Evidence-of-a-large-%CE%B413Ccarb-and-%CE%B413Corg-depth |journal=Geology |language=en |volume=46 |issue=7 |pages=631–634 |doi=10.1130/G40231.1 |issn=0091-7613}}</ref>
*Huangyangshan (HYS) section, Shandong Province <ref name=":10">{{Cite journal |last=Zuo |first=Jingxun |last2=Peng |first2=Shanchi |last3=Qi |first3=Yuping |last4=Zhu |first4=Xuejian |last5=Bagnoli |first5=Gabriella |last6=Fang |first6=Huaibin |date=2018-06-01 |title=Carbon-Isotope Excursions Recorded in the Cambrian System, South China: Implications for Mass Extinctions and Sea-Level Fluctuations |url=http://link.springer.com/10.1007/s12583-017-0963-x |journal=Journal of Earth Science |language=en |volume=29 |issue=3 |pages=479–491 |doi=10.1007/s12583-017-0963-x |issn=1674-487X}}</ref><ref name=":11">{{Cite journal |last=Li |first=Dandan |last2=Zhang |first2=Xiaolin |last3=Hu |first3=Dongping |last4=Chen |first4=Xiaoyan |last5=Huang |first5=Wei |last6=Zhang |first6=Xu |last7=Li |first7=Menghan |last8=Qin |first8=Liping |last9=Peng |first9=Shanchi |last10=Shen |first10=Yanan |date=2018-07-01 |title=Evidence of a large δ13Ccarb and δ13Corg depth gradient for deep-water anoxia during the late Cambrian SPICE event |url=https://pubs.geoscienceworld.org/gsa/geology/article/46/7/631/532092/Evidence-of-a-large-%CE%B413Ccarb-and-%CE%B413Corg-depth |journal=Geology |language=en |volume=46 |issue=7 |pages=631–634 |doi=10.1130/G40231.1 |issn=0091-7613}}</ref>

'''
'''South China:
'''South China:'''
*Huaqiao Formation, Wangcun & Paibi section, Hunan Province <ref name=":7" /><ref name=":12">{{Cite journal |last=Zhu |first=Mao-Yan |last2=Zhang |first2=Jun-Ming |last3=Li |first3=Guo-Xiang |last4=Yang |first4=Ai-Hua |date=2004-03-01 |title=Evolution of C isotopes in the Cambrian of China: implications for Cambrian subdivision and trilobite mass extinctions |url=https://linkinghub.elsevier.com/retrieve/pii/S0016699504000245 |journal=Geobios |language=en |volume=37 |issue=2 |pages=287–301 |doi=10.1016/j.geobios.2003.06.001}}</ref>
*Huaqiao Formation, Wangcun & Paibi section, Hunan Province <ref name=":7" /><ref name=":12">{{Cite journal |last=Zhu |first=Mao-Yan |last2=Zhang |first2=Jun-Ming |last3=Li |first3=Guo-Xiang |last4=Yang |first4=Ai-Hua |date=2004-03-01 |title=Evolution of C isotopes in the Cambrian of China: implications for Cambrian subdivision and trilobite mass extinctions |url=https://linkinghub.elsevier.com/retrieve/pii/S0016699504000245 |journal=Geobios |language=en |volume=37 |issue=2 |pages=287–301 |doi=10.1016/j.geobios.2003.06.001}}</ref>
*Huayansi Formation, Duibian A and B sections, western Zhejiang <ref name=":10" /><ref name=":11" />
*Huayansi Formation, Duibian A and B sections, western Zhejiang <ref name=":10" /><ref name=":11" />
*Upper Chefu & lower Bitiao Formation, Wa’ergang section, Northern Hunan Province <ref name=":12" /><ref name=":11" />
*Upper Chefu & lower Bitiao Formation, Wa’ergang section, Northern Hunan Province <ref name=":12" /><ref name=":11" />
'''Other Areas:
'''Other Areas:'''
*Yaerdang Mountain profile, North-West China''' <ref>{{Cite journal |last=Liu |first=Hu |last2=Liao |first2=Zewen |last3=Zhang |first3=Haizu |last4=Tian |first4=Yankuan |last5=Cheng |first5=Bin |last6=Yang |first6=Shan |date=2017-01-01 |title=Stable isotope (δ13Cker, δ13Ccarb, δ18Ocarb) distribution along a Cambrian outcrop section in the eastern Tarim Basin, NW China and its geochemical significance |url=https://linkinghub.elsevier.com/retrieve/pii/S1674987116300159 |journal=Geoscience Frontiers |language=en |volume=8 |issue=1 |pages=163–170 |doi=10.1016/j.gsf.2016.02.004}}</ref>
*Yaerdang Mountain profile, North-West China''' <ref>{{Cite journal |last=Liu |first=Hu |last2=Liao |first2=Zewen |last3=Zhang |first3=Haizu |last4=Tian |first4=Yankuan |last5=Cheng |first5=Bin |last6=Yang |first6=Shan |date=2017-01-01 |title=Stable isotope (δ13Cker, δ13Ccarb, δ18Ocarb) distribution along a Cambrian outcrop section in the eastern Tarim Basin, NW China and its geochemical significance |url=https://linkinghub.elsevier.com/retrieve/pii/S1674987116300159 |journal=Geoscience Frontiers |language=en |volume=8 |issue=1 |pages=163–170 |doi=10.1016/j.gsf.2016.02.004}}</ref>'''
|-
|-
|'''Australia'''
|'''Australia'''
(4 localities)
(4 localities)
|Gondwana
|Gondwana
| ''' Queensland:
| ''' Queensland: '''
*Mount Murray <ref name=":13" />
*Mount Murray <ref name=":13" />
*Mount Whelan <ref name=":7" /><ref name=":13" />
*Mount Whelan <ref name=":7" /><ref name=":13" />
Line 69: Line 75:
*Arrinthrunga Formation, southern Georgina Basin <ref>{{Cite journal |last=Lindsay |first=John F. |last2=Kruse |first2=Peter D. |last3=Green |first3=Owen R. |last4=Hawkins |first4=Elizabeth |last5=Brasier |first5=Martin D. |last6=Cartlidge |first6=Julie |last7=Corfield |first7=Richard M. |date=2005-12-01 |title=The Neoproterozoic–Cambrian record in Australia: A stable isotope study |url=https://linkinghub.elsevier.com/retrieve/pii/S0301926805001713 |journal=Precambrian Research |language=en |volume=143 |issue=1-4 |pages=113–133 |doi=10.1016/j.precamres.2005.10.002}}</ref>
*Arrinthrunga Formation, southern Georgina Basin <ref>{{Cite journal |last=Lindsay |first=John F. |last2=Kruse |first2=Peter D. |last3=Green |first3=Owen R. |last4=Hawkins |first4=Elizabeth |last5=Brasier |first5=Martin D. |last6=Cartlidge |first6=Julie |last7=Corfield |first7=Richard M. |date=2005-12-01 |title=The Neoproterozoic–Cambrian record in Australia: A stable isotope study |url=https://linkinghub.elsevier.com/retrieve/pii/S0301926805001713 |journal=Precambrian Research |language=en |volume=143 |issue=1-4 |pages=113–133 |doi=10.1016/j.precamres.2005.10.002}}</ref>
'''Central Australia:'''
'''Central Australia:'''
*Goyder Formation, Amadeus Basin''' <ref>{{Cite journal |last=Schmid |first=Susanne |date=2017-02-20 |title=Chemostratigraphy and palaeo-environmental characterisation of the Cambrian stratigraphy in the Amadeus Basin, Australia |url=https://linkinghub.elsevier.com/retrieve/pii/S0009254117300438 |journal=Chemical Geology |language=en |volume=451 |pages=169–182 |doi=10.1016/j.chemgeo.2017.01.019}}</ref>
*Goyder Formation, Amadeus Basin''' <ref>{{Cite journal |last=Schmid |first=Susanne |date=2017-02-20 |title=Chemostratigraphy and palaeo-environmental characterisation of the Cambrian stratigraphy in the Amadeus Basin, Australia |url=https://linkinghub.elsevier.com/retrieve/pii/S0009254117300438 |journal=Chemical Geology |language=en |volume=451 |pages=169–182 |doi=10.1016/j.chemgeo.2017.01.019}}</ref>'''
|-
|-
|'''South Korea'''
|'''South Korea'''
Line 127: Line 133:


=== Proposed Mechanisms ===
=== Proposed Mechanisms ===
⚫
A rise in the atmospheric δ<sup>13</sup>C ratio doesn't necessarily infer a rise in abolute atmospheric carbon concentration. An increase of δ<sup>13</sup>C such as during SPICE is rather interpreted as the result of increased carbon fixation primarily by plants, which fix <sup>12</sup>C more readily than <sup>13</sup>C, and the subsequent burial of this organic carbon in sedimentary rocks. This removal of atmospheric <sup>12</sup>C in higher proportion than <sup>13</sup>C signifies increased proliferation of life and shifts the ratio towards <sup>13</sup>C. This shift during SPICE is interpreted to be a global disturbance in the [[carbon cycle]], affecting the atmosphere and the oceans in equal proportion as described by [[Henry's law]]. Regional sea level changes, a rise in sea water temperatures, ocean anoxia, and [[trilobite]] and [[brachiopod]] extinctions are associated with the SPICE event, although the exact mechanisms causing these events are still unconfirmed.

⚫
One proposed cause of the SPICE is an increase in the burial of organic carbon, perhaps caused by increased primary productivity (e.g. [[photosynthesis]]) or enhanced organic matter preservation due to ocean deoxygenation (i.e. [[Anoxic event|anoxia]] or [[euxinia]]). The spread of seafloor anoxia, facilitated by higher ocean temperatures, has also been proposed as the kill mechanism for the extinctions of marine organisms.


=== Controversies and Comparison to Other Anomalies ===
=== Controversies and Comparison to Other Anomalies ===
<ref>{{Cite journal |last=Brasier |first=M. D. |date=1993-01-01 |title=Towards a carbon isotope stratigraphy of the Cambrian System: potential of the Great Basin succession |url=https://www.lyellcollection.org/doi/10.1144/GSL.SP.1993.070.01.22 |journal=Geological Society, London, Special Publications |language=en |volume=70 |issue=1 |pages=341–350 |doi=10.1144/GSL.SP.1993.070.01.22 |issn=0305-8719}}</ref> <ref name=":1">{{Cite journal |last=Saltzman |first=Matthew |last2=Runnegar |first2=Bruce |last3=Lohmann |first3=Kyger |date=1998-03-01 |title=Carbon isotope stratigraphy of Upper Cambrian (Steptoean Stage) sequences of the eastern Great Basin: Record of a global oceanographic event |url=https://doi.org/10.1130/0016-7606(1998)110<0285:CISOUC>2.3.CO;2 |journal=Geological Society of America Bulletin - GEOL SOC AMER BULL |volume=110 |issue=3 |pages=285- 297}}</ref> <ref name=":6">{{Cite journal |last=Gerhardt |first=Angela M. |last2=Gill |first2=Benjamin C. |date=2016-11-01 |title=Elucidating the relationship between the later Cambrian end-Marjuman extinctions and SPICE Event |url=https://www.sciencedirect.com/science/article/pii/S0031018216303893 |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |volume=461 |pages=362–373 |doi=10.1016/j.palaeo.2016.08.031 |issn=0031-0182}}</ref> <ref>{{Cite journal |last=Schiffbauer |first=James D. |last2=Huntley |first2=John Warren |last3=Fike |first3=David A. |last4=Jeffrey |first4=Matthew Jarrell |last5=Gregg |first5=Jay M. |last6=Shelton |first6=Kevin L. |date=2017-03-03 |title=Decoupling biogeochemical records, extinction, and environmental change during the Cambrian SPICE event |url=https://www.science.org/doi/10.1126/sciadv.1602158 |journal=Science Advances |language=en |volume=3 |issue=3 |doi=10.1126/sciadv.1602158 |issn=2375-2548 |pmc=PMC5336349 |pmid=28275734}}</ref> <ref>{{Cite journal |last=Pulsipher |first=Mikaela A. |last2=Schiffbauer |first2=James D. |last3=Jeffrey |first3=Matthew J. |last4=Huntley |first4=John Warren |last5=Fike |first5=David A. |last6=Shelton |first6=Kevin L. |date=2021-01-01 |title=A meta-analysis of the Steptoean Positive Carbon Isotope Excursion: The SPICEraq database |url=https://www.sciencedirect.com/science/article/pii/S0012825220304888 |journal=Earth-Science Reviews |volume=212 |pages=103442 |doi=10.1016/j.earscirev.2020.103442 |issn=0012-8252}}</ref> <ref name=":17">{{Cite journal |last=Rooney |first=Alan D. |last2=Millikin |first2=Alexie E.G. |last3=Ahlberg |first3=Per |date=2022-03-24 |title=Re-Os geochronology for the Cambrian SPICE event: Insights into euxinia and enhanced continental weathering from radiogenic isotopes |url=https://doi.org/10.1130/G49833.1 |journal=Geology |volume=50 |issue=6 |pages=716–720 |doi=10.1130/g49833.1 |issn=0091-7613}}</ref> <ref>{{Cite journal |last=Zhang |first=Lei |last2=Algeo |first2=Thomas J. |last3=Zhao |first3=Laishi |last4=Dahl |first4=Tais W. |last5=Chen |first5=Zhong-Qiang |last6=Zhang |first6=Zihu |last7=Poulton |first7=Simon W. |last8=Hughes |first8=Nigel C. |last9=Gou |first9=Xueqing |last10=Li |first10=Chao |date=2023-05-12 |title=Environmental and trilobite diversity changes during the middle-late Cambrian SPICE event |url=https://doi.org/10.1130/B36421.1 |journal=Geological Society of America Bulletin |doi=10.1130/b36421.1 |issn=0016-7606}}</ref> <ref>{{Cite journal |last=Westrop |first=Stephen R. |last2=Engel |first2=Michael H. |date=2024-02-01 |title=A record of the Steptoean Positive Carbon Isotope Excursion (SPICE; Cambrian, Paibian) from the Cow Head Group, western Newfoundland |url=https://cdnsciencepub.com/doi/10.1139/cjes-2023-0097 |journal=Canadian Journal of Earth Sciences |language=en |volume=61 |issue=2 |pages=134–144 |doi=10.1139/cjes-2023-0097 |issn=0008-4077}}</ref>
<ref>{{Cite journal |last=Brasier |first=M. D. |date=1993-01-01 |title=Towards a carbon isotope stratigraphy of the Cambrian System: potential of the Great Basin succession |url=https://www.lyellcollection.org/doi/10.1144/GSL.SP.1993.070.01.22 |journal=Geological Society, London, Special Publications |language=en |volume=70 |issue=1 |pages=341–350 |doi=10.1144/GSL.SP.1993.070.01.22 |issn=0305-8719}}</ref> <ref name=":1">{{Cite journal |last=Saltzman |first=Matthew |last2=Runnegar |first2=Bruce |last3=Lohmann |first3=Kyger |date=1998-03-01 |title=Carbon isotope stratigraphy of Upper Cambrian (Steptoean Stage) sequences of the eastern Great Basin: Record of a global oceanographic event |url=https://doi.org/10.1130/0016-7606(1998)110<0285:CISOUC>2.3.CO;2 |journal=Geological Society of America Bulletin - GEOL SOC AMER BULL |volume=110 |issue=3 |pages=285- 297}}</ref> <ref name=":6">{{Cite journal |last=Gerhardt |first=Angela M. |last2=Gill |first2=Benjamin C. |date=2016-11-01 |title=Elucidating the relationship between the later Cambrian end-Marjuman extinctions and SPICE Event |url=https://www.sciencedirect.com/science/article/pii/S0031018216303893 |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |volume=461 |pages=362–373 |doi=10.1016/j.palaeo.2016.08.031 |issn=0031-0182}}</ref> <ref>{{Cite journal |last=Schiffbauer |first=James D. |last2=Huntley |first2=John Warren |last3=Fike |first3=David A. |last4=Jeffrey |first4=Matthew Jarrell |last5=Gregg |first5=Jay M. |last6=Shelton |first6=Kevin L. |date=2017-03-03 |title=Decoupling biogeochemical records, extinction, and environmental change during the Cambrian SPICE event |url=https://www.science.org/doi/10.1126/sciadv.1602158 |journal=Science Advances |language=en |volume=3 |issue=3 |doi=10.1126/sciadv.1602158 |issn=2375-2548 |pmc=PMC5336349 |pmid=28275734}}</ref> <ref name=":18">{{Cite journal |last=Pulsipher |first=Mikaela A. |last2=Schiffbauer |first2=James D. |last3=Jeffrey |first3=Matthew J. |last4=Huntley |first4=John Warren |last5=Fike |first5=David A. |last6=Shelton |first6=Kevin L. |date=2021-01-01 |title=A meta-analysis of the Steptoean Positive Carbon Isotope Excursion: The SPICEraq database |url=https://www.sciencedirect.com/science/article/pii/S0012825220304888 |journal=Earth-Science Reviews |volume=212 |pages=103442 |doi=10.1016/j.earscirev.2020.103442 |issn=0012-8252}}</ref> <ref name=":17">{{Cite journal |last=Rooney |first=Alan D. |last2=Millikin |first2=Alexie E.G. |last3=Ahlberg |first3=Per |date=2022-03-24 |title=Re-Os geochronology for the Cambrian SPICE event: Insights into euxinia and enhanced continental weathering from radiogenic isotopes |url=https://doi.org/10.1130/G49833.1 |journal=Geology |volume=50 |issue=6 |pages=716–720 |doi=10.1130/g49833.1 |issn=0091-7613}}</ref> <ref name=":19">{{Cite journal |last=Zhang |first=Lei |last2=Algeo |first2=Thomas J. |last3=Zhao |first3=Laishi |last4=Dahl |first4=Tais W. |last5=Chen |first5=Zhong-Qiang |last6=Zhang |first6=Zihu |last7=Poulton |first7=Simon W. |last8=Hughes |first8=Nigel C. |last9=Gou |first9=Xueqing |last10=Li |first10=Chao |date=2023-05-12 |title=Environmental and trilobite diversity changes during the middle-late Cambrian SPICE event |url=https://doi.org/10.1130/B36421.1 |journal=Geological Society of America Bulletin |doi=10.1130/b36421.1 |issn=0016-7606}}</ref> <ref>{{Cite journal |last=Westrop |first=Stephen R. |last2=Engel |first2=Michael H. |date=2024-02-01 |title=A record of the Steptoean Positive Carbon Isotope Excursion (SPICE; Cambrian, Paibian) from the Cow Head Group, western Newfoundland |url=https://cdnsciencepub.com/doi/10.1139/cjes-2023-0097 |journal=Canadian Journal of Earth Sciences |language=en |volume=61 |issue=2 |pages=134–144 |doi=10.1139/cjes-2023-0097 |issn=0008-4077}}</ref>


=== References ===
=== References ===

Revision as of 05:28, 26 February 2024

The Steptoean Positive Carbon Isotope Excursion (SPICE) is a global chemostratigraphic event which occurred in the upper Cambrian period , corresponding with the ICS Guzhangian- Paibian stage boundary (as well as the Miaolingian- Furongian series boundary and North American Marjuman- Streptoean stage boundary). [1] This event is characterized by a globally corelated positive excursion of δ13C values in stratigraphy between 497 and 494 million years ago. During this 3 million year period δ13C values increased to maximum values of 4 to 6 ‰ (per mille). The onset of SPICE also corresponds with the End-Marjuman Biomere Extinction. An event which saw significant extinction and turnover in global trilobite and brachiopod species. [2]

Localities and Geology

Map of the world with various countries highlighted in red. Countries include: United States of America, China, Australia, Argentina, Newfoundland (Canada), Korea, France, Kazakhstan, Scotland, and Siberia (Russia)
Modern countries and regions with formations containing the SPICE excursion (highlighted in red). Base world map sourced from GIS Geography (2024).





All Localities SPICE Has Been Observed
Modern Country Paleocontinent Formation
United States

(14 llocalities)

Laurentia Nevada:

Utah:

  • House Range [3][4][5]
  • Lawson Cove Range [6][7]
  • Upper Nouman and lower St. Charles formations [8]

Southern Appalachians:

Other Areas:

  • Eau Claire Formation, Kentucky [15]
  • Franconia Formation, Illinois [16]
  • Rhinehart A-1 corehole (Hollandale "Embayment"), central Iowa [8]
  • Schodack Formation, New York [17]
  • Upper Bonneterre & Davis Formation, Southern Missouri [18][19]
  • Wind River Range, Wyoming [3]
China

(8 localities)

Gondwana North China:
  • Changshan Formation, Tangwangzhai section, Gushan, Shangdong Province [20]
  • Chaomidian Formation, Shandong Province [21][22]
  • Gushan Formation [21][22]
  • Huangyangshan (HYS) section, Shandong Province [23][24]

South China:

  • Huaqiao Formation, Wangcun & Paibi section, Hunan Province [20][25]
  • Huayansi Formation, Duibian A and B sections, western Zhejiang [23][24]
  • Upper Chefu & lower Bitiao Formation, Wa’ergang section, Northern Hunan Province [25][24]

Other Areas:

  • Yaerdang Mountain profile, North-West China [26]
Australia

(4 localities)

Gondwana Queensland:

Northern Australia:

  • Arrinthrunga Formation, southern Georgina Basin [27]

Central Australia:

  • Goyder Formation, Amadeus Basin [28]
South Korea

(2 localities)

Gondwana
  • Machari Formation, Gangweon Province [29]
  • Sesong Formation [30]
Argentina

(2 localities)

Gondwana
  • La Flecha Formation [31]
  • Zonda Formation [31]
Canada

(2 localities)

Laurentia
  • March Point formation, Port au Port group, Newfoundland [8][32][33]
  • Petit Jadin formation, Port au Port group, Newfoundland [33]
France

(2 localities)

Gondwana
  • Val d'Homs formation, Montagne Noire [34]
  • La Gardie formation, Montagne Noire [34]
Kazakhstan

(1 locality)

Kazakhstania
  • Furongian Kyrshabakty section, southern Kazakhstan [35]
Scotland

(1 locality)

Laurentia
  • Eilean Dubh Formation, Northern Scotland [36]
Russia

(1 locality)

Siberia
  • Kulyumbe Formation, Siberian Platform, Siberia [37]
Sweden

(1 locality)

Baltica
  • Alum Shale Formation [38]

Magnitude of the Anomaly and Stages of SPICE

Proposed Mechanisms

A rise in the atmospheric δ13C ratio doesn't necessarily infer a rise in abolute atmospheric carbon concentration. An increase of δ13C such as during SPICE is rather interpreted as the result of increased carbon fixation primarily by plants, which fix 12C more readily than 13C, and the subsequent burial of this organic carbon in sedimentary rocks. This removal of atmospheric 12C in higher proportion than 13C signifies increased proliferation of life and shifts the ratio towards 13C. This shift during SPICE is interpreted to be a global disturbance in the carbon cycle, affecting the atmosphere and the oceans in equal proportion as described by Henry's law. Regional sea level changes, a rise in sea water temperatures, ocean anoxia, and trilobite and brachiopod extinctions are associated with the SPICE event, although the exact mechanisms causing these events are still unconfirmed.

One proposed cause of the SPICE is an increase in the burial of organic carbon, perhaps caused by increased primary productivity (e.g. photosynthesis) or enhanced organic matter preservation due to ocean deoxygenation (i.e. anoxia or euxinia). The spread of seafloor anoxia, facilitated by higher ocean temperatures, has also been proposed as the kill mechanism for the extinctions of marine organisms.

Controversies and Comparison to Other Anomalies

[39] [4] [13] [40] [1] [38] [2] [41]

References

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  2. ^ a b Zhang, Lei; Algeo, Thomas J.; Zhao, Laishi; Dahl, Tais W.; Chen, Zhong-Qiang; Zhang, Zihu; Poulton, Simon W.; Hughes, Nigel C.; Gou, Xueqing; Li, Chao (2023-05-12). "Environmental and trilobite diversity changes during the middle-late Cambrian SPICE event". Geological Society of America Bulletin. doi:10.1130/b36421.1. ISSN 0016-7606.
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  35. ^ Wotte, Thomas; Strauss, Harald (2015-11). "Questioning a widespread euxinia for the Furongian (Late Cambrian) SPICE event: indications from δ 13 C, δ 18 O, δ 34 S and biostratigraphic constraints". Geological Magazine. 152 (6): 1085–1103. doi:10.1017/S0016756815000187. ISSN 0016-7568. {{cite journal}}: Check date values in: |date= (help)
  36. ^ Pruss, Sara B.; Jones, David S.; Fike, David A.; Tosca, Nicholas J.; Wignall, Paul B. (2019-05-01). "Marine anoxia and sedimentary mercury enrichments during the Late Cambrian SPICE event in northern Scotland". Geology. 47 (5): 475–478. doi:10.1130/G45871.1. ISSN 0091-7613.
  37. ^ Kouchinsky, Artem; Bengtson, Stefan; Gallet, Yves; Korovnikov, Igor; Pavlov, Vladimir; Runnegar, Bruce; Shields, Graham; Veizer, Jan; Young, Edward; Ziegler, Karen (2008-05-23). "The SPICE carbon isotope excursion in Siberia: a combined study of the upper Middle Cambrian–lowermost Ordovician Kulyumbe River section, northwestern Siberian Platform". Geological Magazine. 145 (5): 609–622. doi:10.1017/S0016756808004913. ISSN 0016-7568.
  38. ^ a b Rooney, Alan D.; Millikin, Alexie E.G.; Ahlberg, Per (2022-03-24). "Re-Os geochronology for the Cambrian SPICE event: Insights into euxinia and enhanced continental weathering from radiogenic isotopes". Geology. 50 (6): 716–720. doi:10.1130/g49833.1. ISSN 0091-7613.
  39. ^ Brasier, M. D. (1993-01-01). "Towards a carbon isotope stratigraphy of the Cambrian System: potential of the Great Basin succession". Geological Society, London, Special Publications. 70 (1): 341–350. doi:10.1144/GSL.SP.1993.070.01.22. ISSN 0305-8719.
  40. ^ Schiffbauer, James D.; Huntley, John Warren; Fike, David A.; Jeffrey, Matthew Jarrell; Gregg, Jay M.; Shelton, Kevin L. (2017-03-03). "Decoupling biogeochemical records, extinction, and environmental change during the Cambrian SPICE event". Science Advances. 3 (3). doi:10.1126/sciadv.1602158. ISSN 2375-2548. PMC 5336349. PMID 28275734.{{cite journal}}: CS1 maint: PMC format (link)
  41. ^ Westrop, Stephen R.; Engel, Michael H. (2024-02-01). "A record of the Steptoean Positive Carbon Isotope Excursion (SPICE; Cambrian, Paibian) from the Cow Head Group, western Newfoundland". Canadian Journal of Earth Sciences. 61 (2): 134–144. doi:10.1139/cjes-2023-0097. ISSN 0008-4077.
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