John Day Formation

Geology

Members: unnamed (31), Balm Creek (1), Big Basin (4), Haystack Valley (13), Johnson Canyon (4), Kimberly (7), lower Turtle Cove (1), middle (1), Rose Creek (3), Turtle Cove (9)

Lithologies: not reported (20), claystone (5), "shale" (4), siltstone (12), sandstone (19), conglomerate (3), tuff (11)

Paleoenvironments: terrestrial indet. (64), "channel" (1), fluvial-lacustrine indet. (1), lacustrine indet. (8)

Age range: base of the Duchesnean to the top of the Early/Lower Hemingfordian or 40.40000 to 15.97000 Ma
Collections

Time interval Ma Country or state Original ID and collection number
Duchesnean40.4 - 37.2USA (Oregon) (185944)
Chadronian37.2 - 33.9USA (Oregon) (185945)
Orellan33.9 - 33.3USA (Oregon) (17069 17070)
Early/Lower Oligocene33.9 - 28.4USA (Oregon) (31675 35220 35221 35235 35237 35238 35269 117157 117158 193700)
Whitneyan33.3 - 30.8USA (Oregon) (17313 17349 136093)
Geringian30.8 - 26.3USA (Oregon) (17508 17537 93078 159093)
Arikareean30.8 - 20.43USA (Oregon) (17534 93080 170309 170311 180202 188964 188965 188966 188967 188968 189087 189088 189114 212628 212629 228640)
early Late Arikareean30.8 - 20.43USA (Oregon) (36761 36762 36763 36764 36765 36766 36852 36853 36854 36855 36856 170306 170307 180567)
late Early Arikareean30.8 - 20.43USA (Oregon) (160727)
late Late Arikareean30.8 - 20.43USA (Oregon) (18013 18014)
Arikareean - Miocene30.8 - 5.333USA (Oregon) (232149 232150)
Late/Upper Oligocene28.4 - 23.03USA (Oregon) (222667 222668)
Chattian28.1 - 23.03USA (Oregon) (17603 93079 190997)
Monroecreekian - Harrisonian26.3 - 20.43USA (Oregon) (17528)
Monroecreekian - Early/Lower Hemingfordian26.3 - 15.97USA (Oregon) (230864)
Harrisonian24.8 - 20.43USA (Oregon) (19037 170308)
Early/Lower Miocene23.03 - 15.97USA (Oregon) (157001)
Early/Lower Hemingfordian20.43 - 15.97USA (Oregon) (17925 17966 17967 18015 167866 170310 170312)
Hemingfordian20.43 - 15.97USA (Oregon) (17958)