| CzMz - Cenozoic/Mesozoic |
| Cz - Cenozoic (undivided) |
| Q - Quaternary (undivided) |
| T - Tertiary (undivided) |
| N - Neogene |
| Pg - Paleogene |
| TK - Tertiary/Cretaceous |
| MzPz - Mesozoic/Paleozoic |
| Mz - Mesozoic (undivided) |
| K - Cretaceous (undivided) |
| KJ - Cretaceous/Jurassic |
| J - Jurassic (undivided) |
| JTr - Jurassic/Triassic |
| Tr - Triassic (undivided) |
| TrP - Triassic/Permian |
| PzpCm - Paleozoic/Precambrian |
| Pz - Paleozoic (undivided) |
| Pzu - Upper Paleozoic |
| P - Permian (undivided) |
| PC - Permian/Carboniferous |
| C - Carboniferous (undivided) |
| CD - Carboniferous/Devonian |
| D - Devonian (undivided) |
| DS - Devonian/Silurian |
| Pzl - Lower Paleozoic |
| S - Silurian (undivided) |
| SO - Silurian/Ordovician |
| O - Ordovician (undivided) |
| OCm - Ordovician/Cambrian |
| Cm - Cambrian (undivided) |
| pCm - Precambrian (undivided) |
| Pt - Proterozoic (undivided) |
| A - Archean (undivided) |
| und - Undetermined age |
| H2O - Sea and surface water |
| oth - Geology not shown |
