Duchesnean age - Early Chadronian subage

International Chronostratigraphic TimescaleNorth American Land Mammal AgesNorth American Mammal Subages/Zones
18.5
PaleogeneOligoceneChattianArikareeanlate Late Arikareean/early Late Arikareean/late Early Arikareean/early Early ArikareeanHarrisonian23.04
Monroecreekian23.1 *
Geringian24.7 *
Rupelian27.3
Whitneyan29.5
Orellan31.8
EocenePriabonianChadronianLate Chadronian/Middle Chadronian/Early Chadronian33.9
Duchesnean37
Bartonian37.71
UintanLate Uintan/Early Uintan39.7
Lutetian41.03
BridgerianTwinbuttean/Blacksforkian/Gardnerbuttian45.9
Ypresian48.07
WasatchianLostcabinian/Lysitean/Graybullian/Sandcouleean51.1
PaleoceneThanetianClarkforkianCf3/Cf2/Cf156
TiffanianTi6/Ti5/Ti4/Ti3/Ti2/Ti157.5
Selandian59.24
TorrejonianTo3/To2/To160.9
Danian61.66
PuercanPu3/Pu2/Pu163.4
66