Talk:Geology of Mars

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[edit] Query

doi:10.1046/j.1468-4004.2001.42617.x This is the only science article using this word Areology! The other sources in the net are edu servers of some universities which have more advertising character than scientific.

So lets ask the real question: Where das areology come from, and should it go the way all phantasy word should go in wikipedia? --Stone 18:08, 6 December 2006 (UTC)

Just like geo- come from the Greek goddess "Gaia" personifying the Earth, Areology comes from the Greek god Ares (or in Roman Mars), the greek god of war. So if you say the "geology" of Mars, unless geology is put in inverted commas the phrase isn't technically correct. You have a similar naming for other planets. Look up Selenology for "geology" of the moon (although one could argue that since current theory suggests that the moon is derived from the Earth, the "geo" term is perfectly acceptable in this case). I think the reason it is not widely used is becuase people don't want to, even though it is the scientifically correct term.

This discussion mirrors the one we're having about areography but in this case I feel the case is even more clear. I can state without hestitation that professional planetary scientists (like myself) do not use 'areology'. For a concrete example, I just came back from the American Geophysical Union meeting where I attended the following session: http://www.agu.org/cgi-bin/sessions5?meeting=fm06&part=P31B&maxhits=400 I don't think that areology is an "incorrect" term -- it's just not the dominant term and I believe that wikipedia ought to use the dominant term in its titles. Jespley 19:29, 21 December 2006 (UTC)

I would say somebody invented it and one or two used it and the rest never heard of it and should be happy with it.--Stone 23:24, 21 December 2006 (UTC)

Jespley, you say you're a professional planetary scientist, but you fail to say that you're specialisation is planetary atmospheres NOT planetary geology, most planetary scientists I know use the "are-" terms.—Preceding unsigned comment added by 86.134.158.31 (talk) 12:13, 23 December 2006

Fair enough -- I can only speak about my own experience. Nonetheless, I do interact with a lot of "pure" geologists and actually my some of my recent work has direct geological implications. Jespley 23:22, 27 December 2006 (UTC)

Why does nobody use the term in publications? --Stone 11:12, 25 December 2006 (UTC)

[edit] Martian spiders / spherules?

I think it might be appropriate to include a mention of the southern hemispheric Martian spiders and other cryptic region features. These are a geological feature of some notable debate currently. Seems worthy of inclusion in an article of Geological features of Mars? Also, wouldn't hurt to update and expand that article, either.

While we're at it, we might also note the Martian spherules in slightly more detail, with a link to the main article. These also seem to be a geological feature of some notable debate curently. May also note similarity to Moqui Marbles, and Stone spheres of Costa Rica on Earth. There may or may not be common causation between all the similar features. If nothing else, almost perfectly spherical natural objects seem to be slightly rare/mysterious. Just a thought.

Both of these notes could be, if nothing else, short snippets mentioning them and very basic info about what and whree, wit ha link to the "main articles" as they exist currently... Mgmirkin 17:41, 4 November 2006 (UTC)

The following discussion is an archived debate of the proposal. Please do not modify it. Subsequent comments should be made in a new section on the talk page. No further edits should be made to this section.

The result of the debate was PAGE MOVED per request. -GTBacchus(talk) 08:15, 11 January 2007 (UTC)

[edit] Proposed move of Areology to Geology of Mars

FOR As someone who studies the geology of the Moon and Mars, I have to say that "selenology" is a dying term, and Areology is almost never used. Even popular articles use expressions like "geomorpology of mars", "the martian geotherm", and others. These "selono-" and "Are-" terms were introduced as soon as one realized that one could study the geology of the Moon and Mars. However, it was later realized that the same geologic processes operate on these bodies, and it thus made no sense to use separate terms for each planet that describe the same phenomenon. Now that we can study the geology of tens of bodies, the proliferation of new words would become absurd if this practice was carried out to its logical extremum. For instance, what do you call the geology of Io, Ganymede, Titan, Tritan, Pluto, etc.??? And what is geometry when you are on Mars? Finally, many find these terms to be pretentious. Lunokhod 17:02, 9 January 2007 (UTC)

Also, please consult with planetary geology. Lunokhod 17:12, 9 January 2007 (UTC)

Support: As mentionen at Areography and Areology pages there is no literature using this term. --Stone 19:37, 9 January 2007 (UTC)

Support: Wikipedia article titles ought to use the most prevalent term for the subject matter. Areo- terms are not commonly used in general discussion (do a Google search) and in modern professional settings are almost never used (from personal experience and Google searches). However, a sentence within the articles about the areo- terms is quite appropriate. Jespley 21:53, 10 January 2007 (UTC)

The above discussion is preserved as an archive of the debate. Please do not modify it. Subsequent comments should be made in a new section on this talk page. No further edits should be made to this section.

[edit] More formally known as Areology?

A recent edit has changed to introductory sentence from "sometimes known as Areology" to "formally known as Areology". As is clear from the above discussion, this page was moved from "Areology of Mars" to "Geology of Mars" because this is, in fact, not true. If the author of this change does not add a reference attesting to the verifiability of this statement, I will revert back to "sometimes known as." Lunokhod 13:16, 17 January 2007 (UTC)

[edit] Information about the Core

The core may be completely fluid. See recent article, Science (vol 316, p 1323), for new work on Fe-S solidus. Additionally, same phrases about the core in two places, removed one of them -changes were reverted, redid them. Seorwz 20:09, 7 June 2007 (UTC)Seorwz

[edit] Central dynamo collapse

The reference which has been provided [1] to support the phrase "polarity reversal of its dipole field occurred when the central dynamo collapsed, leaving only residual permanent crustal dipoles" does not mention dynamo collapse as far as I can see sbandrews (t) 15:10, 19 August 2007 (UTC)

You're right. I gave the wrong cite. I'll have to chase it down again. Mea culpa. LeadSongDog 13:51, 24 August 2007 (UTC)

[edit] The ionosphere is everywhere and crustal fields aren't necessarily dipoles

I don't have the inclination or time to look up detailed references for every little correction I make but I'll point you to review articles by Connerney and Nagy in Space Science Reviews from about 2004. If anyone really wants these citations then you should be able to find them with google or ads. Jespley 15:59, 18 October 2007 (UTC)

Here, I found them. These two references should cover most anything basic about plasma (including the ionosphere) and crustal fields at Mars. Unfortunately, they require subscriptions but any major research library will have one. http://adsabs.harvard.edu/abs/2004SSRv..111...33N http://adsabs.harvard.edu/abs/2004SSRv..111....1C Jespley 16:27, 18 October 2007 (UTC)

Thank you for the refs. I didn't think you really intended implying that Mars is host to the only Magnetic monopoles ever found. On the other hand if you want to say something to the effect that the crustal magnetic field is composed of a complex superposition of many static and induced dipoles, go ahead and make it explicit. While the Nagy articles are not in open journals, there are references to them, such as this.
They help to elucidate that to correctly interpret the satellite based magnetic data one has to be sensitive to the time-of-sol and use the diurnal variations to distinguish induced from permanent features. I think we can presume that competent researchers would have considered this. More subtly, it raises the question of whether the locked-in stripes in the crustal field could have been originally caused simply by temporal variations in the iononspheric field over the time period the crust cooled rather than changes in a central magnetic core. If there's analysis on that line of thinking it would certainly be worthy of mention.LeadSongDog 16:56, 18 October 2007 (UTC)
Yeah, it'd be pretty cool if they were monopoles but sadly I have no evidence for that. :) My edit regarding the dipoles was, as you surmised, related more to the fact that the fields aren't necessarily best represented as a bunch of little dipoles. Some have to tried to model them as such (cf. papers by Purucker et al.) but these models have not been well accepted (cf. Connerney, SSR, 2004 and Brain, JGR, 2006). Other models have been created using spherical harmonics (cf. papers by Arkani-Hamed or Cain). In reality, of course the actual magnetic fields are surely a tremendously complicated mess of superimposed fields created from the individual magnetic mineral grains.
As to the magnetic stripes, it's highly unlikely that they were created by variations in the ionosphere. I'm not aware of any research pursuing this idea. The amplitude of the fields in the ionosphere is too small (40 nT) and the time scale for their variations (~sec, min, days) is too short.
And yes, removing the external (i.e. ionospheric/solar wind) contributions from the measured fields so that one is left with only the intrinsic (e.g. crustal) fields is an important but tricky business (cf. http://www.lpi.usra.edu/meetings/lpsc2007/pdf/2019.pdf).
Jespley 18:15, 18 October 2007 (UTC)

[edit] catenae & a shifting crust

Years ago, Science News reported on an article, that claimed that catenae on Mars suggested, that the crust as a whole has shifted over time. Sorry, can't find it in the SN archives; it might be too old (say from Viking). The only explanation they could come up with for these four very long crater chains was the breaking up and impact of small moons, and the older the chains, the higher the angle they were from the equator. They speculated that the mass of Olympus and Tharsis as they formed may have destabilized the rotation of the planet, and the crust shifted to compensate, presumably after the cessation of any tectonic activity. Has this been followed up, and is it still thought reasonable? kwami (talk) 21:52, 20 November 2007 (UTC)


[edit] Noachian Era

I've always read that the Noachian era was between 4.6 bya and 3.5 bya. However, on Wikipedia it says 3.8 bya to 3.5 bya. I have some references such as http://phoenix.lpl.arizona.edu/mars174.php as well as a textbook which agrees. However, I have no idea how to cite my change or even do the footer, so if anyone would like to help, thanks! 68.228.85.87 (talk) 14:58, 19 March 2008 (UTC)Kevin 3/19/2008

Edit: I have the textbook reference now. Croswell, Ken. Magnificent Mars, 188. New York, New York: Free Press, 2003. —Preceding unsigned comment added by 68.228.85.87 (talk) 15:05, 19 March 2008 (UTC)