The GSSP for the base of the Chattian Stage(Paleogene System,Oligocene Series)is defined at meter level 197 in the Monte Cagnero section,which belongs to the pelagic succession of the Umbria–Marche basin(Urbania,cent...The GSSP for the base of the Chattian Stage(Paleogene System,Oligocene Series)is defined at meter level 197 in the Monte Cagnero section,which belongs to the pelagic succession of the Umbria–Marche basin(Urbania,central Italy:43°38′47.81″N–12°28′03.83″E).This level with an astronomical age of 27.82 Ma coincides with the highest common occurrence of the planktonic foraminifer Chiloguembelina cubensis at the base of planktonic foraminiferal O5 Zone and falls in the upper part of calcareous nannofossil NP24 Zone,in the lower part of dinocyst Dbi Zone,and in the lower Chron C9n.The proposal was approved by the International Subcommission of Paleogene Stratigraphy in July 2015,approved by the International Commission of Stratigraphy in August 2016,and ratified by the International Union of Geological Sciences in September 2016.展开更多
In June 2016 the Paleogene,Neogene,and Quaternary subcommissions(ISPS,SNS,SQS)of the International Commission on Stratigraphy(ICS)voted on whether to formalize sub-series and their geochronologic equivalents,sub-epoch...In June 2016 the Paleogene,Neogene,and Quaternary subcommissions(ISPS,SNS,SQS)of the International Commission on Stratigraphy(ICS)voted on whether to formalize sub-series and their geochronologic equivalents,sub-epochs.The vote required a 60 percent majority for the proposal to be forwarded to the ICS for further consideration.That majority was not achieved,albeit by a narrow margin,hence sub-series and sub-epochs are currently to be regarded as informal,and if used should carry a lower case modifier,as in lower Miocene and early Pleistocene.To accompany the vote,those who favoured continuation of informal usage were asked to prepare a short summary of the main arguments in support of their viewpoint.展开更多
The global stratotype sections and points for the bases of the Selandian(Middle Paleocene)and Thanetian(Upper Paleocene)stages have been defined in the coastal cliff along the Itzurun Beach at the town of Zumaia in th...The global stratotype sections and points for the bases of the Selandian(Middle Paleocene)and Thanetian(Upper Paleocene)stages have been defined in the coastal cliff along the Itzurun Beach at the town of Zumaia in the Basque Country,northern Spain.In the hemipelagic section exposed at Zumaia the base of the Selandian Stage has been placed at the base of the Itzurun Formation,ca.49 m above the Cretaceous/Paleogene boundary.At the base of the Selandian,marls replace the succession of Danian red limestone and limestone-marl couplets.The best marine,global correlation criterion for the basal Selandian is the second radiation of the important calcareous nannofossil group.展开更多
The GSSP for the base of the Lutetian Stage(early/middle Eocene boundary)is defined at 167.85 metres in the Gorrondatxe sea-cliff section(NW of Bilbao city,Basque Country,northern Spain;43°22'46.47"N,3&#...The GSSP for the base of the Lutetian Stage(early/middle Eocene boundary)is defined at 167.85 metres in the Gorrondatxe sea-cliff section(NW of Bilbao city,Basque Country,northern Spain;43°22'46.47"N,3°00'51.61"W).This dark marly level coincides with the lowest occurrence of the calcareous nannofossil Blackites inflatus(CP12a/b boundary),is in the middle of polarity Chron C21r,and has been interpreted as the maximumflooding surface of a depositional sequence that may be global in extent.The GSSP age is approximately 800 kyr(39 precession cycles)younger than the beginning of polarity Chron C21r,or~47.8 Ma in the GTS04 time scale.The proposal was approved by the International Subcommission on Paleogene Stratigraphy in February 2010,approved by the International Commission of Stratigraphy in January 2011,and ratified by the International Union of Geological Sciences in April 2011.展开更多
文摘The GSSP for the base of the Chattian Stage(Paleogene System,Oligocene Series)is defined at meter level 197 in the Monte Cagnero section,which belongs to the pelagic succession of the Umbria–Marche basin(Urbania,central Italy:43°38′47.81″N–12°28′03.83″E).This level with an astronomical age of 27.82 Ma coincides with the highest common occurrence of the planktonic foraminifer Chiloguembelina cubensis at the base of planktonic foraminiferal O5 Zone and falls in the upper part of calcareous nannofossil NP24 Zone,in the lower part of dinocyst Dbi Zone,and in the lower Chron C9n.The proposal was approved by the International Subcommission of Paleogene Stratigraphy in July 2015,approved by the International Commission of Stratigraphy in August 2016,and ratified by the International Union of Geological Sciences in September 2016.
文摘In June 2016 the Paleogene,Neogene,and Quaternary subcommissions(ISPS,SNS,SQS)of the International Commission on Stratigraphy(ICS)voted on whether to formalize sub-series and their geochronologic equivalents,sub-epochs.The vote required a 60 percent majority for the proposal to be forwarded to the ICS for further consideration.That majority was not achieved,albeit by a narrow margin,hence sub-series and sub-epochs are currently to be regarded as informal,and if used should carry a lower case modifier,as in lower Miocene and early Pleistocene.To accompany the vote,those who favoured continuation of informal usage were asked to prepare a short summary of the main arguments in support of their viewpoint.
文摘The global stratotype sections and points for the bases of the Selandian(Middle Paleocene)and Thanetian(Upper Paleocene)stages have been defined in the coastal cliff along the Itzurun Beach at the town of Zumaia in the Basque Country,northern Spain.In the hemipelagic section exposed at Zumaia the base of the Selandian Stage has been placed at the base of the Itzurun Formation,ca.49 m above the Cretaceous/Paleogene boundary.At the base of the Selandian,marls replace the succession of Danian red limestone and limestone-marl couplets.The best marine,global correlation criterion for the basal Selandian is the second radiation of the important calcareous nannofossil group.
基金Financial support was mainly provided by different projects of the Ministry of Science and Innovation of Spain,the Town Council of Getxo and the Basque Government.
文摘The GSSP for the base of the Lutetian Stage(early/middle Eocene boundary)is defined at 167.85 metres in the Gorrondatxe sea-cliff section(NW of Bilbao city,Basque Country,northern Spain;43°22'46.47"N,3°00'51.61"W).This dark marly level coincides with the lowest occurrence of the calcareous nannofossil Blackites inflatus(CP12a/b boundary),is in the middle of polarity Chron C21r,and has been interpreted as the maximumflooding surface of a depositional sequence that may be global in extent.The GSSP age is approximately 800 kyr(39 precession cycles)younger than the beginning of polarity Chron C21r,or~47.8 Ma in the GTS04 time scale.The proposal was approved by the International Subcommission on Paleogene Stratigraphy in February 2010,approved by the International Commission of Stratigraphy in January 2011,and ratified by the International Union of Geological Sciences in April 2011.
