The geologic timescale: Where did those names come from? Here’s some etymological information I share with my Historical Geology students so that the names become meaningful symbols of ideas, rather than simply of bunch of nonsensical gibberish to memorize…
Phanerozoic eon – Greek for “visible life”
Cenozoic era – Greek for “new life”
Quaternary – Latin for “fourth”
Holocene – Greek for “entirely new”
Pleistocene – Greek for “mostly new”
Neogene – Greek for “new birth / generation”
Pliocene – Greek for “more new”
Miocene – Greek for “less new”
Paleogene – Greek for “ancient birth / generation”
Oligocene – Greek for “few new”
Eocene – Greek for “dawn of the new”
Paleocene – Greek for “ancient new”
* Tertiary (Latin for “third”) is an archaic term left over from the Wernerian chronology. It is no longer officially used as part of the geologic timescale.
Mesozoic era – Greek for “middle life”
Cretaceous — Latin word for chalk (“creta”) and was first applied to extensive deposits of this age that form white cliffs along the English Channel between Great Britain and France.
Jurassic – named after the Jura Mountains between France and Switzerland, where rocks of this age were first studied.
Triassic – refers to the threefold division of rocks of this age in Germany.
Paleozoic era – Greek for “ancient life”
Permian – named after the province of Perm, Russia, where rocks of this age were first studied
Carboniferous – named after the high carbon content of coal-bearing strata of this age in the United Kingdom
Pennsylvanian (US usage)– named after the state of Pennsylvania (USA), where rocks of this age are widespread
Mississippian (US usage)– named after the Mississippi River valley (USA), which contains good exposures of rocks of this age
Devonian – named after Devon, England (UK), where rocks of this age were first studied
Silurian – named after a Celtic tribe called the Silures (UK).
Ordovician – named after a Celtic tribe called the Ordovices (UK).
Cambrian – Roman name for Wales (UK), where rocks of this age were first studied
Precambrian* – all the time prior to the start of the Cambrian (not a formal era/eon name)
* synonymous with “Cryptozoic” – Greek for “hidden life”
Proterozoic eon – Greek for “former life”
Neoproterozoic – Greek for the “new” Proterozoic
Mesoproterozoic – Greek for the “middle” Proterozoic
Paleoproterozoic – Greek for the “ancient” Proterozoic
Archean eon – Greek for “ancient”
Hadean eon – Greek for “hellish” or “unseen” (the Netherworld)
Here’s a Geologic Names handout that I use in my Historical Geology class — feel free to use it if it’s useful to you. Typically, I pass it out in conjunction with page 2 of this excellent geologic timescale visualization from the Kentucky Geological Survey.
“Devonshire”? Would that be near Pennsylvaniashire and Mississippishire? The county is called Devon!
Okay – forgive my unfamiliarity with the conventions of naming places in the UK. I’ve updated it to read “Devon” only, without the “shire” bit. Thanks for the correction.
I’ve been meaning to sit down and put all that together for some time and that Kentucky geologic survey document is excellent. Thank you
“* Tertiary (Latin for “third”) is an archaic term left over from the Wernerian chronology. It is no longer officially used as part of the geologic timescale.”
I like Tertiary and always have. What makes you say that it is no longer “officially” used?
The ICS nixed it back in 2003: http://www.stratigraphy.org/column.php?id=Chart/Time%20Scale
and here’s an article about it when it happened:
http://www.agiweb.org/geotimes/nov03/NN_tertiary.html
Hmm, but GSA still has it listed on theirs.
Indeed they do. Like you, a lot of American geologists like it and want to keep it.
Here’s the rationale GSA offers, such as it is:
The names “Tertiary” and “Precambrian” were not dropped on the new time scale. The Quaternary, the status and boundaries of which are still being debated, was modified to reflect some of the pending recommendations. These differences were retained to best reflect the needs of GSA members and Divisions.
They didn’t really go into any reason for it other than, that’s what us Americans like. I also feel they should flip-flop Eocene and Paleocene because they don’t make sense the way they are but that is a different argument.
Many people do like the idea of “Tertiary”, but is not up to GSA what is (or isn’t) official. There are also geologists out of the USA, and that is why it is up to the IUGS 🙂
Great post, Callan! Thank you for this and the resources. I remember having to re-memorize the Geologic table almost every semester as an undergrad. This would have helped, and is most interesting now!
Thanks for the comments. If there are any corrections or suggestions, please send them on. I have also developed an Excel workbook that performs the calculations for user selected time/calendar or distance scales. Just send me an email, bnuttall@uky.edu.
Oh, Callan, by the way, Carboniferous is widely used in the whole of Europe and Africa, not just in UK.
Great article.
Edited. Thanks.
The Carboniferous is the official System/Period name: the Pennsylvanian and Mississippian have the unusual rank of Subsystem/Subperiod, as approved by the ICS in 2004.
Duly noted. Thanks.
very interesting. thanks for your nice effort.
Fantastic post… thanks so much.