Talk:Geologic time scale

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	Geologic time scale is a former featured article. Please see the links under Article milestones below for its original nomination page (for older articles, check the nomination archive) and why it was removed.
Article milestones Date Process Result December 1, 2004 Refreshing brilliant prose Not kept January 1, 2004 Featured article candidate Promoted March 8, 2004 Featured article review Demoted November 10, 2004 Peer review Reviewed May 18, 2024 Peer review Reviewed Current status: Former featured article

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Text and/or other creative content from this version of Template:Geologic time scale was copied or moved into Geologic time scale with this edit on August 6, 2015. The former page's history now serves to provide attribution for that content in the latter page, and it must not be deleted as long as the latter page exists.

Text and/or other creative content from this version of User:Jarred_C_Lloyd/Articles/GeologicTimeScale_Terminology was copied or moved into Geologic time scale with this edit on June 5, 2022. The former page's history now serves to provide attribution for that content in the latter page, and it must not be deleted as long as the latter page exists.

This article was reviewed by The Roanoke Times on July 1, 2005. Comments: Geologist Bob Bodnar of Virginia Tech found "the terminology and ages used [in the article] to be quite accurate and consistent with the most recent data." See the Wikipedia Signpost article. For more information about external reviews of Wikipedia articles and about this review in particular, see this page.

Merging the geological timeline articles? Geologic time scale - Timeline of the evolutionary history of life - Timeline of human evolution

The following discussion is closed. Please do not modify it. Subsequent comments should be made in a new section. A summary of the conclusions reached follows.

Not merged, there is a clear consensus that the two topics should be covered on their own pages despite some level of overlap. PrimalMustelid (talk) 14:12, 11 May 2024 (UTC)[reply]

---

I am interested in the past of Earth and life, a fan of extinct lifeforms, but I am not an expert in any relevant field, i.e. I am not a professional geologist, palaeontologist, palaeoclimatologist or something like that.

Nevertheless, while browsing articles, I found this article to significantly overlap with Timeline of the evolutionary history of life and at least partially with Timeline of human evolution. Thus I propose merging this article with Timeline of the evolutionary history of life and refocusing Timeline of human evolution towards Hominidae or at least primate evolution specific dates. Of course, the first Bilateria represent an important milestone, but such milestones can be explained in this article or Timeline of the evolutionary history of life in my opinion. PragmaFisch (talk) 17:11, 11 November 2023 (UTC)[reply]

You apparently don't understand the timescale. Evolutionary and geological are very different. --Fama Clamosa (talk) 19:26, 11 November 2023 (UTC)[reply]

I do see the point - however, Geologic time scale contains quite a lot of information on life and its evolution, too. Might that be better suited to Timeline of the evolutionary history of life? Also, I love Geologic time scale most because the scrollable timetable with the common colours and explanations etc. which provides an excellent overview. Maybe this at least could be incorporated into Timeline of the evolutionary history of life? PragmaFisch (talk) 19:34, 11 November 2023 (UTC)[reply]

Oppose Despite some extent of overlap given their geological natures, geologic time scale and timeline of the evolutionary history of life are two different concepts, the former focusing on the stratigraphic side and the latter focusing on the paleobiological side. Merging the two pages would result in an excessively long page. They both can overlap in discussing stratigraphic ranges of life forms, but for the geologic time scale page, it's not the main topic. PrimalMustelid (talk) 19:01, 12 November 2023 (UTC)[reply]

I would be opposed to merging the two, as the only real overlap seems to be the fact that they both use the same division of deep time and the fact that the timeline on this article also has some information on what was happening at the time, also pertaining to life that existed. The topics they cover (those being stratigraphic and paleobiological) are quite far apart, and merging them together would result in a much messier article than either of the two seperate ones. The Morrison Man (talk) 15:57, 13 November 2023 (UTC)[reply]

Oppose - the timelines each have a different scope: geological development of Earth, lifeforms, human lifeform; each of which needs its own chronological reckoning.    — The Transhumanist   11:16, 30 April 2024 (UTC)[reply]

Oppose - There is inevitably some overlap between the timelines but any sort of combined timeline would not, in my view, do any of the topics justice. Mikenorton (talk) 13:49, 30 April 2024 (UTC)[reply]

Oppose - While there is some overlap due to the nature of how geological time is defined and how biologicial evolution in inherently linked with geologic processes, merging of the two articles would not do either topic justice. As it stands, I believe both articles are able to elaborate on their specific topics in better detail and with greater cohesion and readability than a merged article would be able to do. Jarred C Lloyd (talk) 12:11, 1 May 2024 (UTC)[reply]

The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

Feedback

As a non-expert I took a quick look at this article based on a request for feedback on the Geology project Talk.

I think the ICC, ICS, etc makes the article less approachable. I would start by moving 'Major proposed revisions to the ICC' down or even in to a separate article. This content is very detailed for the overall topic. Throughout the article I would avoid the acronyms or at least group them in to one paragraph for a section. The concept of these organizations is important for the article but their operating details are not. For example, the second sentence of Terminology,

• These are represented on the ICC published by the ICS; however, regional terms are still in use in some areas.

could easily go at the end of the section. Similarly the second paragraph of Principles.

The critical "Principles" section is too short. Rather than the bullet list, consider wp:summary paragraphs.

I would swap the order of "Divisions of geologic time" and the stuff before it which is full of VeryBigWords. The divisions section has more common words that readers can relate to.

I don't understand why there are two tables.

HTH. Johnjbarton (talk) 02:40, 2 October 2024 (UTC)[reply]

Hi Johnjbarton,

Thanks for the quick feedback, particularly as a non-expert. I'll have a go at implementing some of these suggestions shortly.

Do you think the proposed revisions section warrants its own article? Personally, I think it is a bit light for its own article, but agree that it has quite a lot of detail. I'd happily move it below the "Table of geologic time", and above, "Non-Earth..."

With reference to "Divisions of geologic time" and stuff before it, are you suggesting I move the divisions part ahead of "Chronostratigraphy is..."? I understand the VeryBigWords point you are making – I had placed the text as current so the terms like chronostratigraphic unit are defined prior to their use in the divisions.

There are multiple tables, which two are you referring to? Jarred C Lloyd (talk) 04:38, 2 October 2024 (UTC)[reply]

When I started on wikipedia I thought that articles should have a similar length. Now I think that the variety of lengths is a big advantage. Each article can be as long as needed to cover the topic and no more. A separate article on the "proposed revisions" would be free of the requirement to match the level of readers trying to understand "geologic time scale" for the first time. It could use ICC jargon without confusing the reader.

I also have a different suggestion: move the ICC revisions content to International Commission on Stratigraphy. Seems like that would make this article and the Commission article stronger.

I suggest describing "chronostratigraphy" and "geochronologic", perhaps less formally, in the first paragraph of Principles and again in Divisions. Maybe break it down, "time-layers" and "rock-dating". These words are key. Any reader who fails to understand or is put off by these words cannot proceed.

I was referring to the compound table in "Naming of geologic time" and long one in "Table of geologic time". I see now why you have two. I think the "Table of geologic time" should come much earlier as this is what many readers imagine the article will discuss. Maybe the Naming table could be in History? Johnjbarton (talk) 15:43, 2 October 2024 (UTC)[reply]

Comments from Cas Liber

I reckon go for Good Article status first. Much easier and will give feedback that is essential for FAC.

If a plain word can be substituted for a jargon word without losing meaning then do it

every sentence should be referenced - putting comments in like this can make for easier reading

article has only 22 kb readable prose, so could be expanded to double the size before it needs splitting.

Good luck. Busy right now - will look more later. Cas Liber (talk · contribs) 05:20, 2 October 2024 (UTC)[reply]

Thanks Cas Liber,

On some feedback at Wikipedia talk:WikiProject Geology, I think GAN will be a sensible option in future. Currently it will fail immediately under the verifiable references criteria, mainly due to the "Table of geologic time" where people have added to the events column over many years without citing sources...it will be a Hurculean task to rectify this. I think it will be good to work on improving the rest of the article first where possible, then attempt to address that issue. Jarred C Lloyd (talk) 10:05, 2 October 2024 (UTC)[reply]

New edition of ICS chart

There is a new edition of the ICS stratigraphy chart (as of December 2024 - https://stratigraphy.org/ICSchart/ChronostratChart2024-12.pdf ).

Here is a list of changes: https://stratigraphy.org/ICSchart/ChangeLog2012-2024.txt

Should these be included in their respective articles? IvarTheBoneless123 (talk) 16:27, 24 December 2024 (UTC)[reply]

Yes, despite its recency, this source has extensive review and a track record. Johnjbarton (talk) 17:41, 24 December 2024 (UTC)[reply]

Error on first diagram reg. Appearance of first Hominins: 2 MYA instead of 6-7 MYA

Timing on first Picture of the Article states wrong first Hominins 2MYA: Lucy's (the famous Astralopithecus) skeleton with upright walking was dated 3+ MYA, and we separated from our with the Chimpanzees common ancestors around 6.5 MYA. The oldest group of hominins walking on two legs (bipedalism) found to date are the species Sahelanthropus tchadensis and Orrorin tugenensis found in Chad and Kenya who date back 6-7 MYA (acc. to History of the World Map by Map, p. 12f, published by Dorling Kindersley Limited, 2023) Spetkoff (talk) 08:29, 6 November 2025 (UTC)[reply]

2mya marks the appearance of the genus Homo, you're right. @Jarred C Lloyd: would it be possible for you to either change the label or the time? Thanks, Mikenorton (talk) 10:25, 6 November 2025 (UTC)[reply]

Referencing error in table of geologic events

I've realised I've screwed up some of the references in the table. I've worked out what I've done and how to fix it, so please bear with me while I sort it. Silica Cat (talk) 18:46, 16 December 2025 (UTC)[reply]