Lower Ordovician
General info
Belongs to
Type chronostratigraphy
Rank Series
Scope global
Status formal standard
Age top (Ma) 470
Age base (Ma) 485.4
Index
O1
Alt. index
O1
Date added 2003-03-23
Date changed 2022-11-04
Stratotypes
LocalityTypeFrom (m)1To (m)2ReferenceRemarks
Green Point Section, western Newfoundland
boundary stratotype
101.8 Cooper et al., 2001 GSSP for the Tremadocian Stage
StratigraphyIndexIndex add'lTypeRankScopeBelongs toAge base (Ma)Age top (Ma)Age
Tremadocian
chronostratigraphy
Stage
global
Lower Ordovician 485.4 477.7
Floian
chronostratigraphy
Stage
global
Lower Ordovician 477.7 470