Talk:Sediment

Formula

If we assume that r is the radius of the particle, the constant in the formula should be 2/9 (4.5) rather than 1/18, because this is true for the diameter being squared in the formula.

The Stokes forumla only applies to small particles (fine sand and smaller), in which the wake behind the settling particle is laminar. For large particles (coarse sand and gravel), an emperical equation to account for flow turbulence should be used over the Stokes formula (e.g., see Dietrich, 1982).

The Settling article agrees with you, don't know why the difference. Settling through still fluid as opposed to a flowing fluid? hmm... no reference given. I'll change it and see if anyone disagrees. _Vsmith 00:45, 1 Feb 2005 (UTC)

Ferguson and Church (2006, I believe) have a new formula that analytically gives the same result as Dietrich (1982)'s result and fits all of their data by combining the drag law with Stokes' law, and connecting the two with a transition zone. And if we start talking about sediment transport and bedload vs. suspended load, we should talk about fall velocity and about shear velocity and the Rouse number. Maybe in order to actually do the subject of sediment transport justice without muddling "sediment" with two much complexity, a new page should be made about it and "sediment" should link to it. Awickert (talk) 21:52, 14 July 2008 (UTC)

I'm following up and re-vamping sediment transport. See this article and Sediment transport. Awickert (talk) 19:55, 15 July 2008 (UTC)

Is sediment a synonym to alluvium? /Habj 15:08, 13 Jun 2005 (UTC)

See Talk:Alluvium Vsmith 17:38, 13 Jun 2005 (UTC)

Merge from Transportation (sediment) and Deposition (sediment)

These processes are very similar, and are already discussed in this article to some degree.

Also, this article doesn't have a clear distinction between transportation and deposition, as it is kind of mixed together in a mess.<Looks like this has been cleared up> It would also be nice to mention the basic [latin] diagenetic types: colluvium, fluvium, alluvium, and eluvium. +mwtoews 22:46, 3 November 2006 (UTC)

i think this article needs more information like the diffrent types of depostion and crap like that

I agree with the last section, that the article on deposits would be more complete if their were sections focusing on the diffrent types of deposits. I do not think it would be wise to merge this article on depositation with that on sediment. I feel sediment is more about the movement, and deposits are what happens when sediment is no longer moving. Also, I was looking at this artice to get a basis for coal deposits, and don't think anyone would call it coal sediment. 129.15.107.142 19:01, 21 February 2007 (UTC)

Separate article needed for Bedload

The topic of bedload needs its own article, since bedload often consists of pebble and gravel materials (which can be transported within the stream as well as deposited). Cuvette 19:23, 29 June 2007 (UTC)

This is really a B class article???

If you want to be minimalist, perhaps this is a b class article. It lacks the following: images of sediment deposits Description of sediment size classes and their properities Description of aeolian processes and examples of aeolian derived deposits. Description of soil movement. These are generally called landslides. Images would be helpful. Description of glacial sediment deposits. Description of the function of sediment in stream channels and floodplains. The equations for stream form are not included and only mentioned in an offhand way. There is a general lack or references in all sections. There is a general lack of links to other articles that either cover the above, or complement the subject at hand.

This article reads like an expanded stub. I would give it a C- if it were turned in as a composition.

This paragraph is totally spurious. It is more polemic than information. If it is useful then it needs to be complemented by descriptions of other sources of sediments in other places, such as clear cut, normal sedimentation rates, farm erosion in western europe and china....blah blah blah... If it is still in the article without other additions when I return next I will delete it.

"One of the main causes of riverine sediment load siltation stems from slash and burn treatment of tropical forests. When the ground surface is stripped of vegetation and then seared of all living organisms, the upper soils are vulnerable to both wind and water erosion. In a number of regions of the earth, entire sectors of a country have been rendered erosive; for example, on the Madagascar high central plateau, comprising approximately ten percent of that country's land area, virtually the entire landscape is sterile of vegetation, with gully erosive furrows typically in excess of 50 meters deep and one kilometer wide. Shifting cultivation is a farming system which sometimes incorporates the slash and burn method in some regions of the world. The resulting sediment load in rivers flowing to the west is ongoing, with most rivers a dark red brown colour, also leading to massive fish kills."

Avram Primack (talk) 16:50, 8 November 2008 (UTC)

I agree with your point - there are a large number of problems that need to be addressed, and it should probably be reclassified as a somewhat extended stub. If you would like to edit this article, I'm sure it would be appreciated. I would, however, like to advise you that Wikipedia is a volunteer-created entity, and that while I agree with the deficiencies you outline, the wording of your comments are not in the proper tone of constructive criticism.

But to address what you say more specifically, I think that we could decide on one of two plans of attack. We could either make "sediment" a comprehensive page only about sediment itself, and as a general index with short introductory blurbs for modes of transport and deposition, etc., or we could make it be large and comprehensive. I would say that the former would probably be better, as it allows clear-cut categorization of articles. "Sediment" should probably be stripped down in its generality and beefed up in what it specifically says about sediment. The writing should be improved as well. This would address your concerns. By limiting the scope of the article "sediment" making those deficiencies the issue of other articles (many of which already address what you brought up), the reader would not expect to see what you were disappointed not to see.

Awickert (talk) 04:22, 9 November 2008 (UTC)

Picture illustrating "sedimentation"

The picture of carbonate precipitation in a stream in Switzerland is not an example of sedimentation, but rather a chemical process due to chemical saturation. The picture should be removed, as it is not an example of mechanical sedimentation. 193.64.21.60 (talk) 20:43, 6 March 2012 (UTC)

The Rhone/Lake Geneva image? Where does it state that is a carbonate precipitate? And even if it is, then it would be a chemical sediment - and still appropriate. Although the article doesn't discuss such chemical sediments. Vsmith (talk) 23:46, 6 March 2012 (UTC)

The caption was definitely wrong, so I changed it. The pale color of the waters of the upper Rhone is almost entirely due to glacial flour, not the product of poor land use or industrial development. It is not chemical saturation either, the rocks of the high Alps along the upper Rhone valley are not high in carbonate content. See the Wikipedia writeup on the Arve River for a similar image of high sediment loads from another high alpine source (and a correct explanation of their source). Douglas W. Jones (talk) 16:11, 24 November 2020 (UTC)