Talk:Fossilization (palaeontology)

Carbonate preservation

I am reading this article, which is indeed good - one of the finest among Earth Science I should say. I have some questions about carbonate preservation, though.

• Ideal conditions for carbonate preservation are normally found in organic-rich shelf sediments

Why organic-rich? Organic matter decay usually lower the pH, leading to dissolution. Or, do you mean "rich in living organisms" which shells may be fossilized? If so, this concept could be expressed more clearly.

• Sulfate reduction is required for cementation to occur

Not sure about that. Do you have a reference for this? Note that seawater is naturally supersaturated with respect to calcium carbonate. Also, cementation in continental environments (e.g., caves, travertines) do not need sulphur to take place.

Just two minor notes. Keep on going with the good job! --Nereo Preto 09:37, 27 September 2007 (CDT)

Ok, I saw the changes. Thanks, great job! --Nereo Preto 13:21, 2 October 2007 (CDT)

Overview

Another note. Could you add some lines in the overview where you explain the steps one dead part should pass through to get fossilized? Like, deposition, burial, diagenesis... I believe this is important, because there are terms used in the text (e.g., diagenesis, but you may also want to write about biostratinomy or taphonomy somewhere) which need to be defined. (BTW, parhaps, there are such lines already - I admit I couldn't find the time to read all text carefully...) --Nereo Preto 09:43, 27 September 2007 (CDT)

Good job

Good job, Natasha. I wonder, however--will we have another article, with a different focus, titled fossil? The title, and the article so far, describes mainly the process. Will it concern only the process, or will it concern fossils generally speaking? If so you should link the first instance of fossil. --Larry Sanger 12:11, 27 September 2007 (CDT)

Developed, kind-of

This article is substantially developed in my view... save that it is mostly about fossilization in continental environments rather than marine environments. This is because the main author is a student of Dinosaurs, so she is continental-oriented. Which is ok, of course, the contents are rich and really good. In fact, if not for the fact the marine stuff is underrepresented, this article could be driven to approval in a reasonable time perhaps.

So, first of all, my compliments to User:Natasha Barbolini. You did a great work so far!

Second: if anyone wish to work on fossilization in marine environments, I'm ready to take care of this article's approval. Most fossils and rocks are marine, though, so the marine part is essential.

--Nereo Preto 05:51, 3 October 2007 (CDT)

Metadata

This article appears to be in British English, with -ize endings [i.e. Oxford English] so I have inserted that as the language variant. I have also promoted it to category 1, as it seems to be fully developed. Apologies if that is not correct, and revert if needed.--Martin Baldwin-Edwards 06:51, 6 October 2007 (CDT)

Mmm... ok, sure enough is one of the most complete in Earth Sciences. Let's keep it in category 1, this is correct with respect to the average of the workgroup, though see above: we need text about fossilization in marine environments. Compliments to the author(s): this is the first developed article of this workgroup! --Nereo Preto 06:59, 6 October 2007 (CDT)

endocranial cast

the illustration shows an endocranial cast of a. africanus. ; the text in the paragraph next to talks about casts as being external. this needs to be clarified. (And unless am mistaken, isn't "cast' used also for one prepared in the museum from a specimen to make a copy of it? )

Towards Approval

I see that this article is certainly close to approval. Is there an Earth Sciences or Anthropology editor that can take a look and let Natasha know if there is anything else needed. Otherwise, Natasha, your next step is to contact the editors of these workgroups and see if someone is ready to nominate this article for approval. Good luck, let me know if I can help with the mechanics of how to do nominate this article. --Matt Innis (Talk) 19:35, 28 October 2007 (CDT)/constable

As a side note, this is a student project article, so time is critical. Also note that Professor Berger is teaching a collaborative process and wants Citizendium authors and editors to go ahead and make any appropriate changes on the article they feel are necessary (content or style), so jump in wherever. Treat this just like any other article on Citizendium. --Matt Innis (Talk) 19:43, 28 October 2007 (CDT)

I started going through the article. The first thing I note is we have a summary here, which is great. I suggest to move it to the top (see my edit), it gives the reader motivation to continue and makes the function of the abstract of scientific papers. Not sure my layout is the best possible, though...

Second point is also about easy-reading. Where the steps to fossilization are listed (overview chapter), it would be GREAT to have a small table giving the names of these steps (i.e., death, deposition, biostratinomic processes and so on) and, in a second column, a brief definition (copy-and-pasted from main text?).

Further comments as I'll read more carefully. Great job so far, hope we can really approve! --Nereo Preto 09:07, 5 November 2007 (CST)

I'll try below to act purely as editor, i.e., suggesting changes (which can be discussed. More: discussion is welcome and encouraged) without actually editing the text. Hope authors won't feel like in a class because of this - it is not my intention anyways. --Nereo Preto 05:12, 10 November 2007 (CST)

Conditions for preservation

Within this chapter, I see a problem. Two conditions for preservation, which I believe are perhaps the most important, are cited late in the text and their importance is apparently underestimated.

• The first is, marine organisms are much easely fossilized than continental ones. The main reason for this is that marine environments are normally depositional, while most terrestrial environments are erosional, or depositional only episodically.
• The second is hard parts. It is true hard parts are not a must for fossilization, but preservation of soft tissues is always considered an exceptional instance. This should be clarified in the text, and perhaps highlighted.

--Nereo Preto 05:12, 10 November 2007 (CST)

A minor comment: microbes (bacteria mostly) should be listed under the destructive agents, especially because they are then cited later in the text (e.g. where it is pointed out that cold and anoxia hamper bacterial decomposition). --Nereo Preto 05:12, 10 November 2007 (CST)

"Deep marine environments accumulate sediment and would bury marine plants and animals, but most of these fossils are still submerged in ocean depths.": This is true only for not-so-old oceanic sediments, and not always anyways. Actually, the majority of sedimentary rocks cropping out on continents are marine, and yield indeed plenty of marine (and terrestrial in some instances) fossils. Ocean sediments and rocks, even from deep ocean environments, are piled in accretionary wedges at active plate margins and then uplifted in mountain chains, especially during continental collisions. Sequences of oceanic crust (including their sedimentary cover) uplifted and exposed on land are called Ophiolites (suppose we don't have this yet of course).

I don't think all this needs to be explained in this article, but the quoted sentence is inaccurate in the light of all this, so I suggest it should be rephrased in some way. --Nereo Preto 05:21, 10 November 2007 (CST)

Summary

I think the summary box is strictly unnecessary. The first section of every article should contain a summary of the topic, so that's where that text belongs. --Larry Sanger 09:51, 5 November 2007 (CST)

A good solution here would be to merge the contents of the present introduction to those of the summary in the box, and then drop the box. I suppose this is how the article should evolve.

I must admit, however, that my personal preference would be to have an introduction AND a summary or abstract, the latter hihglighted in some way. This comes from my experience in reading scientific papers. When the article gets long and my time short, abstracts are fundamental: they save me a lot of time when I realize that it was not what I was looking for. --Nereo Preto 12:06, 7 November 2007 (CST)

Towards approval (2)

N. Barbolini did a great job bringing this article to developed stage. I have acted as editor as much as I could till now, but now I wish to contribute substantially and fill the gap to approval - which is possible in my view. It will take time, as long as I'll be the sole contributor - academic duties steal much of my time.

It should be clear someone else should take care of the approval once the process is nearly finished, I'll won't be a really neutral editor by that time! I'll also need help with final copyediting as I'm not native English - grammar and spelling errors are likely to remain unnoticed!

Any help is welcome. --Nereo Preto 06:06, 2 December 2007 (CST)

I'll help

I'll keep and eye on it and I'll go monitor it as you near the end.

Lee R. Berger 08:51, 4 December 2007 (CST)