The base of the Quaternary System is defined by theGlobal Stratotype Section and Point(GSSP)of theGelasian Stage at Monte San Nicola in Sicily,Italy,currently dated at 2.58 Ma.The base of the PleistoceneSeries is rede...The base of the Quaternary System is defined by theGlobal Stratotype Section and Point(GSSP)of theGelasian Stage at Monte San Nicola in Sicily,Italy,currently dated at 2.58 Ma.The base of the PleistoceneSeries is redefined by the same GSSP,having previouslybeen defined by the GSSP at Vrica,Calabria,Italy,whichis dated at 1.806 Ma.These important changes to thegeological time scale were formulated through extensiveconsultation with the Quaternary community throughthe International Union for Quaternary Research(INQUA),proposed by the International Commission onStratigraphy’s(ICS)Subcommission on QuaternaryStratigraphy,endorsed by the voting membership of theICS,and ratified in June 2009 by the Executive Committeeof the International Union of Geological Sciences.Twocompeting proposals had been advanced:a‘Neogene’proposal advocated by the ICS Subcommission on NeogeneStratigraphy,and a‘Quaternary’proposal championedby the ICS Subcommission on Quaternary Stratigraphy.The status quo position would have persisted hadneither proposal received a majority of votes.Theseproposals are compared and evaluated,the‘Quaternary’proposal is presented in detail,and future directions arediscussed.展开更多
文摘The base of the Quaternary System is defined by theGlobal Stratotype Section and Point(GSSP)of theGelasian Stage at Monte San Nicola in Sicily,Italy,currently dated at 2.58 Ma.The base of the PleistoceneSeries is redefined by the same GSSP,having previouslybeen defined by the GSSP at Vrica,Calabria,Italy,whichis dated at 1.806 Ma.These important changes to thegeological time scale were formulated through extensiveconsultation with the Quaternary community throughthe International Union for Quaternary Research(INQUA),proposed by the International Commission onStratigraphy’s(ICS)Subcommission on QuaternaryStratigraphy,endorsed by the voting membership of theICS,and ratified in June 2009 by the Executive Committeeof the International Union of Geological Sciences.Twocompeting proposals had been advanced:a‘Neogene’proposal advocated by the ICS Subcommission on NeogeneStratigraphy,and a‘Quaternary’proposal championedby the ICS Subcommission on Quaternary Stratigraphy.The status quo position would have persisted hadneither proposal received a majority of votes.Theseproposals are compared and evaluated,the‘Quaternary’proposal is presented in detail,and future directions arediscussed.
