| Similarity | Rank | |
|---|---|---|
| cretaceous | 0.910 | 15845 |
| palaeozoic | 0.909 | 17635 |
| ordovician | 0.905 | 22032 |
| triassic | 0.903 | 19513 |
| mesozoic | 0.895 | 21369 |
| silurian | 0.888 | 24411 |
| miocene | 0.886 | 31987 |
| devonian | 0.882 | 17422 |
| namurian | 0.882 | 53188 |
| precambrian | 0.880 | 28924 |
| eocene | 0.872 | 39949 |
| pleistocene | 0.872 | 19850 |
| facies | 0.871 | 23456 |
| carboniferous | 0.870 | 10443 |
| breccia | 0.870 | 37637 |
| metamorphic | 0.867 | 30217 |
| dinantian | 0.865 | 48032 |
| archaean | 0.864 | 68387 |
| post-glacial | 0.859 | 38769 |
| grainstone | 0.858 | 43255 |
| gneiss | 0.856 | 38681 |
| proterozoic | 0.856 | 68404 |
| zechstein | 0.851 | 33130 |
| glaciation | 0.849 | 30769 |
| dalradian | 0.848 | 31062 |