Middle Jurassic (Bajocian) Eastern Oregon

IV CONTENTS
PLATE 38. Docidoceras and Docidoceras?
39. Otoites and Emileia.
40. Normannites (Masckeites?), Normannites?, Megasphaeroceras, Chondroceras, Sphaeroceras, Oppelia, and Lissoceras.
41. Normannites (Epalxites), N. (Itinsaites), and N. (Normannites).
42. Stephanoceras (Skirroceras).
43, 44. Stephanoceras (Skirroceras) and Stephanoceras.
45. Stephanoceras (Phaulo::;tephanus?), S. (Skirroceras), and Stephanoceras.
46. Stemmatoceras, Teloceras, Zemistephanus? and Stephanoceras (Skirroceras).
4 7. Lupherites, Leptosphinctes, L. (Prorsisphinctes?), and Parabigotites.
48. Index maps showing general and detailed positions of Bajocian ammonite localities in eastern Oregon.
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FIGURE 1. Chart showing correlation of some Middle Jurassic (Bajocian) formations in eastern Oregon, California, and
Alaska________________________________________________________________________________________ 10
2. Columnar sections of the Weberg Member of the Snowshoe Formation, Suplee area________________________ 12
3-8. Chart showing-·.
3. Stratigraphic distribution of Bajocian ammonite species in the Weberg Member of the Snowshoe Formation
in the Suplee area________________ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 17
4. European ranges of certain Bajocian ammonite genera present in eastern Oregon_____________________ 19
5. Correlation of Bajocian ammonite faunas in eastern Oregon, Alaska, and Europe_____________________ 21
6. Stratigraphic distribution of Bajocian ammonite species in the Warm Springs and Basey Members of
the Snowshoe Formation in the Suplee area__________________________________________________ 23
7. Stratigraphic distribution of Bajocian ammonite species in the Snowshoe Formation in the Izee area____ 26
8. Stratigraphic distribution of Bajocian ammonite genera in the Snowshoe Formation in the Suplee, Izee,
Seneca, and Emigrant Creek areas__________________________________________________________ 27
TABLES
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TABLE 1. Ammonite genera and subgenera of Bajocian age in eastern Oregon, showing biological relationships and number of
specimens available for study______________________________________________________________________ 3
2. Morphological comparisons of the various species of Sonninia (Euhoploceras) in eastern Oregon__________________ 6
3. Comparisons of Bajocian ammonites in eastern Oregon and southern Alaska__________________________________ 31
4. Comparisons of Bajocian ammonites in eastern Oregon and Europe__________________________________________
5-10. Geographic distribution of Bajocian ammonites-
36
5. In the Weberg Member of the Snowshoe Formation in the Suplee area_______________________________ 38
6. In the Warm Springs Member of the Snowshoe Formation in the Suplee area_________________________ 40
7. In the Basey Member of the Snowshoe Formation in the Suplee area_________________________________ 40
8. In the Snowshoe Formation in the lzee area_______________________________________________________
9. In the Snowshoe Formation in the Emigrant Creek area in Harney County and the Seneca area in Grant
41
County___________________________________________________________________________________ 42
10. In unnamed Jurassic beds in Malheur and Baker Counties__________________________________________ 43