Talk:Mya (unit)

mya vs ma
why did someone decide 'ma' is better than 'mya'?

mya is simple direct, to the point. only problem is its in english...

then again, why not have the 'ago' translated into latin or whatever. it makes no snse to just say 'xyz happened 500 years'. —Preceding unsigned comment added by Decora (talk • contribs) 16:36, 30 December 2008 (UTC)

Myr is the standard of duration and Ma is the standard of date. Example: The mountain belt formed at 10 Ma = The mountain belt formed 10 million years ago The transform fault was inactive for 10 Myr until the catastrophic event at 2 Ma = The transform fault was inactive for 10 million years until the catastrophic event 2 million years ago. It would be convinient to refer to M.-P. Aubry, J. A. Van Couvering, N. Christie-Blick, E. Landing, B. R. Pratt, D. E. Owen, and I. Ferrusquia-Villafranca. Terminology of geological time: Establishment of a community standard. STRATIGRAPHY, 6(2):100–105, 2009. --Leonardo.quevedo (talk) 01:36, 17 March 2011 (UTC)
 * mya does not equal myr.

Cepadrome! (talk) 21:43, 11 December 2013 (UTC)

To Wiktionary?
(William M. Connolley 15:32, 20 Feb 2005 (UTC)) This page is (usefully) linked from a number of wiki pages. Why move it to wiktionary? I would rather it not be moved; but it should go to wacronym, not wiktionary, anyway :-)
 * The problem is that the page is no more than a dictionary definition of several related terms, which is what Wiktionary is there for. (See What_Wikipedia_is_not) Simon 19:26, Feb 21, 2005 (UTC)

Theoretically, someone could turn it into a list of acronyms used in geology. If that were to happen, however, I would have to recommend they think of a better title than mine. - Vague | Rant 09:22, Mar 19, 2005 (UTC)


 * I strongly agree with William H. Connolley that this page should not be moved to Wiktionary. We have articles for other units used in science, as well as time abbreviations like BC, so there is no reason this page should be moved to Wiktionary. &mdash;Lowellian (talk) 05:08, May 27, 2005 (UTC)


 * This article should be replaced by a redirect to the modern Mega-annum. Just listing a bunch of things that were on the order of a million years ago doesn't rescue the article.  It is conceptually redundant with Bya etc, each being simply a multiple of ya.  Worse, the Bya suffers from the Long and short scales ambiguity. However silly the idea of 10^12 years ago may seem to short scale adapted scientists or to followers of the Ussher chronology, some readers will still be confused by it.  Tagged as rfd. Please pursue discussion there. LeadSongDog 20:57, 24 July 2007 (UTC)


 * I messed up the process for RfD, which lead to speedy close. I'll take another crack, this time using multiple merge onto Annum.  See below and my talk for more history.LeadSongDog 20:16, 25 July 2007 (UTC)


 * Ok, so I've now added a multiplemergerfrom tag on Annum pointing talk to here, plus advised a bunch of recent editors to this article and its originator. I look forward to a discussion over the coming days.


 * I agree with the idea of making the terms consistent, and it would be OK with me to have it all redirected to Mega-annum as LeadSongDog suggests. There has been some attempt, usually changed later by others, to use Ma or Ga consistently in geology articles (those are the terms of choice for professionals and I think they are increasingly showing up in popular literature, if the phrase is not written out) but it keeps getting changed to mya or bya. I also agree that the list of things at about 1 million years is silly to have on this article. And I support the idea of keeping it in Wikipedia, as it is not simply a definition, the article(s) can include items of usage and alternatives, for example. Cheers Geologyguy 22:11, 25 July 2007 (UTC)

Light years
I believe the Light Years section is somewhat ambiguously mixed with other years and mya, so someone might came to the wrong conclusion that ly is also a unit of time (not quite uncommon to happen!). It should be reorganized somehow or explicitly marked as distance unit, to avoid that possibility. --Arny 20:18, 27 February 2006 (UTC)


 * Mention of light years was pointless and irrelevant. It is gone now.
 * Urhixidur 22:44, 27 February 2006 (UTC)

Title
The title should be changed to Ma (unit). Outside of the english speaking world nobody uses Mya, the international convention is Ma (mega annum). Now this is an english encyclopedia, but the term used in literature is Ma, because most of the authors are not native in english. Let's stick to the scientific conventions. Woodwalker 10:10, 5 June 2006 (UTC)

On second thought, I suppose this article could better be merged with Annum. I see no additional value. Woodwalker 12:49, 5 June 2006 (UTC)

Change title
I agree with woodwalker (comment above). Besides, English-speaking scientists use "Ma" rather than "mya" (e.g., see Gradstein et al. 2004 - A geologic time scale 2004, Cambridge University Press). I never met "mya" in my professional career, so I suppose it is now a word in disuse.

Kaapitone 18:47, 30 October 2006 (UTC)


 * Note that Ma was also the chemical symbol for masurium. B.Wind (talk) 04:00, 28 February 2008 (UTC)

Coherent discussion of similar articles
The result was merge into Annum. -- LeadSongDog (talk) 20:35, 1 May 2008 (UTC)

I consider that the very similar articles tya, kyr, mya (unit), myr, bya, byr should be handled consistently, barring arguments to the contrary. This seems to be the most active talk pages, so I've added on each of the other's talk pages a link to this one. There are no ky (unit), my (unit), or by (unit) articles, although there are unrelated articles ky, my and by.LeadSongDog 17:14, 25 July 2007 (UTC)

Agree. Ma should also be included in the discussion. These are all units for very long periods of time, used mostly in specialistic literature. It would be pointless to have separate (and sometimes contradictory) articles for them. --Kaapitone 09:53, 31 July 2007 (UTC)
 * I agree: there should be one article, in which the suffices M- (mega), G- (giga), b- (billion), T- (tera) and k- (kilo) are linked and explained. Myr/My is the same as Ma. Ma is internationally used, Myr only in the English-speaking world, so Ma would be a better title for an article (specialists would use Ma). Even better, I would use annum as a title for the merged article. Woodwalker 13:35, 10 August 2007 (UTC)


 * There is actually a difference in the way specialists use Ma and Myr. The first is used for elapsed time, as in, e.g., "The beginning of Mesozoic is at ca. 250 Ma" - that is, millions of years ago. The second is for time as a measure unit, as in "The duration of Mesozoic is less than 200 Myrs". Without a single article explaining these things, people would never get oriented in these complex issues. --Kaapitone 08:58, 15 September 2007 (UTC)


 * This has had plenty of time. Closing discussion.  LeadSongDog (talk) 20:35, 1 May 2008 (UTC)

Neanderthal sep?
Neanderthal's have only been found in Europe, so it seesm odd that the sep is put before the expansion out of Africa. Worth some checking.Snori 00:32, 7 November 2007 (UTC)
 * Neanderthal indicates a range of dates for initial/complete separation.LeadSongDog 04:09, 7 November 2007 (UTC)

Milky way...
The light we (do not) see now from the centre of the Milky Way started 0.026 mya

Uh... what does mean this? Without an explanation, I believe it should be deleted. --Kaapitone 14:09, 10 November 2007 (UTC)
 * It means the editor didn't understand relativity. There are lots of people in that situation, it's no shame. LeadSongDog (talk) 20:37, 6 May 2008 (UTC)

Merge?
I see up top that this was supposed to be merged...why isn't it? Fruckert (talk) 01:44, 28 July 2009 (UTC)

Tautology
"Myr is in common use where the term is often written" ... Seems to be a pointless statement. — Preceding unsigned comment added by 131.107.0.116 (talk) 22:19, 10 May 2013 (UTC)

why doesn't somebody put some information on this page?
I don't understand why somebody doesn't put some information on this page. Cepadrome! (talk) 21:41, 11 December 2013 (UTC)

ka, Ma, Ga for date; kyr, Myr, Gyr for duration
the following article

http://www.ldeo.columbia.edu/~ncb/Selected_Articles_all_files/25_Stratigraphy.6.100.pdf

proposes


 * ka, Ma, Ga for date
 * kyr, Myr, Gyr for duration

Quessler (talk) 17:21, 21 March 2015 (UTC)