geological period
period
Carboniferous
Cretaceous
Mesozoic
Silurian
argillaceous
coal-bearing
fossiliferous
fresh-water
geologic
gold-bearing
huronian
marly
metamorphic
oil-bearing
oolitic
schistose
slaty
superincumbent
tertiary
Amazonian
Apollonian
Babylonian
Bostonian
Caledonian
Estonian
Jacksonian
Jeffersonian
Melkonian
Newtonian
Oregonian
Patagonian
Plutonian
Simonian
Smithsonian
Washingtonian
amazonian
apollonian
bostonian
draconian
gorgonian
patagonian