| Ar Archean |
| Ar-Pr Archean and Proterozoic |
| Ar-Pr1 Archean and Lower Proterozoic |
| Archean Alkaline |
| Archean Basic |
| Archean Granite and Granodiorite |
| Archean Volcanic |
| C Carboniferous |
| C-J Carboniferous to Jurassic |
| C-P Carboniferous and Permian |
| C-P1 Carboniferous to Lower Permian |
| C-Tr Carboniferous to Triassic |
| C1 Lower Carboniferous |
| C2 Upper Carboniferous |
| C2-P1 Upper Carboniferous to Lower Permian |
| Cm Cambrian |
| Cm-D Cambrian to Devonian |
| Cm-O Cambrian and Ordovician |
| Cm-S Cambrian to Silurian |
| Cm1 Lower Cambrian |
| Cm12 Lower and Middle Cambrian |
| Cm2 Middle Cambrian |
| Cm23 Middle and Upper Cambrian |
| Cm3 Upper Cambrian |
| Cenozoic Basic |
| Cenozoic Volcanic |
|
| D Devonian |
| D-C Devonian and Carboniferous |
| D-C1 Devonian to Lower Carboniferous |
| D1 Lower Devonian |
| D12 Lower and Middle Devonian |
| D2 Middle Devonian |
| D23 Middle and Upper Devonian |
| D3 Upper Devonian |
| D3-C Upper Devonian to Carboniferous |
| Ice |
| J Jurassic |
| J-K Jurassic and Cretaceous |
| J-K1 Jurassic to Lower Cretaceous |
| J1 Lower Jurassic |
| J12 Lower and Middle Jurassic |
| J2 Middle Jurassic |
| J23 Middle and Upper Jurassic |
| J3 Upper Jurassic |
| J3-K1 Upper Jurassic to Lower Cretaceous |
| K Cretaceous |
| K1 Lower Cretaceous |
| K1-Pg Lower Cretaceous to Paleogene |
| K1-Pg1 Lower Cretaceous to Paleocene |
| K2 Upper Cretaceous |
| K2-Pg Upper Cretaceous and Paleogene |
| K2-Pg1 Upper Cretaceous to Paleocene |
| Mz Mesozoic |
| Mesozoic Alkaline |
| Mesozoic Basic |
| Mesozoic Granite and Granodiorite |
| Mesozoic Syenogranite |
| Mesozoic Ultramafic |
| Mesozoic Volcanic |
| N Neogene |
| N-Q Neogene and Quaternary |
| N1 Miocene |
| N2 Pliocene |
| N2-Q Pliocene to Quaternary |
|
| N2-Q1 Pliocene to lower Quaternary |
| O Ordovician |
| O-D Ordovician to Devonian |
| O-S Ordovician and Silurian |
| O1 Lower Ordovician |
| O23 Middle and Upper Ordovician |
| P Permian |
| P1 Lower Permian |
| P2 Upper Permian |
| P-J Permian to Jurassic |
| P-Tr Permian to Triassic |
| P2-Tr Upper Permian to Triassic |
| Pg Paleogene |
| Pg-N Paleogene and Neogene |
| Pg1 Paleocene |
| Pg2 Eocene |
| Pg2-N1 Eocene to Miocene |
| Pg23 Eocene and Oligocene |
|
| Pg3 Oligocene |
| Pg3-N1 Oligocene to Miocene |
| Pr Proterozoic |
| Pr-Cm Proterozoic to Cambrian |
| Pr-Pz1 Proterozoic to lower Paleozoic |
| Pr1 Lower Proterozoic |
| Pr12 Lower and Middle Proterozoic |
| Pr2 Middle Proterozoic |
| Pr23 Middle and Upper Proterozoic |
| Pr23-Cm Middle and Upper Proterozoic to Cambrian |
|
| Pr3 Upper Proterozoic |
|
| Pr3-Cm Upper Proterozoic to Cambrian |
| Pr3-Pz1 Upper Proterozoic to lower Paleozoic |
| Pr3-S Upper Proterozoic to Silurian |
| Proterozoic Alkaline |
| Proterozoic Basic |
| Proterozoic Diorite |
| Proterozoic Granite and Granodiorite |
| Proterozoic Syenogranite |
| Proterozoic Ultramafic |
| Proterozoic Volcanic |
| Pz Paleozoic |
| Pz-Mz Paleozoic and Mesozoic |
| Pz1 Lower Paleozoic |
| Paleozoic Alkaline |
| Paleozoic Basic |
| Paleozoic Diorite |
| Paleozoic Granite and Granodiorite |
| Paleozoic Syenogranite |
| Paleozoic Ultramafic |
| Paleozoic Volcanic |
| S Silurian |
| S-D Silurian and Devonian |
| S1 Lower Silurian |
| S2 Upper Silurian |
| Tr Triassic |
| Tr-J Triassic and Jurassic |
| Tr1 Lower Triassic |
| Tr12 Lower Middle Triassic |
| Tr2 Middle Triassic |
| Tr23 Middle and Upper Triassic |
| Tr3 Upper Triassic |
| Tr3-J1 Upper Triassic to Lower Jurassic |
