The geological time scale summarizes the divisions of geological time. It is based mainly on the extinction and evolution of life forms, but also the changes of the earth's land surface and oceans. The time scale has been in use for about two hundred years, but the numbers – dates in millions of years – have been known for less than one hundred years, and are being continually improved and better understood.
To learn about the Geological Time Scale and the Earth's fascinating geological history, go to this web site.
To memorize the order of geological periods (one of the first things geology students must memorize) you can use mnemonics. You will find many choices of good mnemonics at this web site.
To memorize the numbers in the time scale, you can use Pseudonumerology. You need to find a pseudonume that you can associate with each of the periods. In the short list below, I have used the Ponderous Pseudonumer® to find pseudonumes for the main numbers of the 1982 time scale.
(If you just found this page directly from the internet and still don't know what a pseudonume is, you must go back to the home page, Pseudonumerology.com and read about it. Then learn to pseudospell, which takes a few minutes, before returning to this page.)
|
|
|
|
|
|
|
|
|
|
|
|
| Arabic numerals: |
|
|
|
|
|
|
|
|
|
|
Beginnings of the periods in the 1982 Geological Time Scale
| Period | Age | Pseudonume How the pseudonume can be remembered |
| Tertiary | 66 m.y. | Ouch-ouch! the dinosaurs suddenly become extinct. |
| Cretaceous | 145 m.y. | T-rule Tyrannosaurus (T-Rex) rules in the end of the Cretaceous |
| Jurassic | 208 m.y. | No safe no one is safe from the meat-eaters. |
| Triassic | 245 m.y. | New role the dinosaurs appear and lead a new role in evolution |
| Permian | 290 m.y. | Knobs knobs of Permain rocks stand up in the Oslo area |
| Carboniferous | 362 m.y. | Matchin' Carboniferous (coal) is lit by "matching" with a lighted match |
| Devonian | 408 m.y. | Erosive erosive forces dominate the Devonian |
| Silurian | 439 m.y. | Ramp the Silurian strata are characterized by ramp structures |
| Ordovician | 510 m.y. | Lots the Ordovician rocks in Norway contain lots of fossils | Cambrian | 570 m.y. | Legs in the Cambrian period the first animals with legs appeared |
Since 1982, the time scale has been much improved. The ages are now more precisely defined, by analyses of radioactive rocks that were collected from the borders. These new precise dates – for periods, epochs, and ages – should really be known by geologists who are working with rocks of these periods.
Pseudonumes for remembering the beginnings of the epochs
Based on the time scale of Gradstein & Ogg, in Episodes v.19, no. 1 & 2 1996:
Period/epoch/age (date) mnemonic pseudonume that gives the beginning date
Albian (112.2) Alps toting
Aptian (121.0) apartment tents
Barremian (127.0) barrel tanks
Hauterivian (132.0) hot river demons
Valanginian (136.5) valentine card to Michelle
Ryanzanian (142.0) rain drains
Callovian (164.4) call-off the huge roar
Bathonian (169.2) bath dishpan
Bajocian (176.5) ba-juice thick jelly
Aalenian (180.1) alien two-faced
Toarcian (189.6) two arcs (McDonalds arches) tough peach
Pliensbachian (195.3) plane diploma
Sinemurian (201.9) sine-curve instep, sign-more no-stop
Hettangian (205.7) hat no silk
Mississippian
Serphukovian (327) serp<ent monkey
Visean (342) vise hammering
Tournaisian (354) turn easy miller's wheel