Lithostratigraphy
Tertiary
| Aquitanian | Lincoln Creek formation (Priabonian – Aquitanian) |
| Chattian | Lincoln Creek formation (Priabonian – Aquitanian) |
| Rupelian | Lincoln Creek formation (Priabonian – Aquitanian) |
| Priabonian | Chuckanut formation (Selandian – Priabonian) Lincoln Creek formation (Priabonian – Aquitanian) |
| Bartonian | Chuckanut formation (Selandian – Priabonian) |
| Lutetian | Chuckanut formation (Selandian – Priabonian) |
| Ypresian | Chuckanut formation (Selandian – Priabonian) Nanjemoy formation |
| Thanetian | Chuckanut formation (Selandian – Priabonian) |
| Selandian | Chuckanut formation (Selandian – Priabonian) |