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Delta shapes

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Deltas come in a multitude of plan-view shapes, as their characteristics are determined by the balance between the energy and sediment load of a separation system and the quality of the ocean. Various ways of classifying deltas have been devised. One of the more widely used schemes is based on deltaic form as it reflects controlling energy factors, which means that its a river that flows out to sea but as it drages dirt and debris from the river bed it blocks up the exit course wich makes the river flood and find or create a new river to let the water flow out of this provides a shallow swamp wich provides fresh water but still alows plantlife to grow their so if your planning a resourt it would be goog to let cattle go and graze in the delta. But the bad thing is that when it floods it can wipe out wildlife, Indogar villages and cattle. --Gcpeoples (talk) 08:38, 21 June 2008 (UTC)[reply]

Images

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Image:Ganges River Delta, Bangladesh, India.jpg was added to the article today. I had felt the article already had its maximum number of images relative to the size of text. Nonetheless, I was hoping to add Image:Mississippi Delta Lobes.jpg, because it demonsrates something of an opposite of the Nile delta... eg. one that has more deltaic switching. Would anyone else be in favor of adding it in place of the Ganges image? --Interiot 17:18, 24 December 2005 (UTC)[reply]

If your point is the one I think it is, the picture would be a constructive addition and might reasonably oust the Ganges picture. This last is not as informative as it might be. (RJP 22:00, 14 January 2006 (UTC))[reply]

Could someone please tell me what the suggested picture actually shows and/or means? --—Preceding unsigned comment added by 86.17.147.38 (talkcontribs)

While I don't know for sure what Interiot had in mind, there r two sorts of delta; the one epitomized by the Nile, in which the river breaks up into diverging streams in a broadly triangular plan - like the Greek capital letter Δ. The other sort is typified by the Mississippi. The river retains a main channel enclosed by levees, and has extended seawards. The levees leak relatively small streams into the sea along the adjoining coast but the silt in the main channel has allowed the levees to grow out into the sea to near the edge of the continental shelf.
There is no fundamental difference but the Mississippi delta is an example at the latter extreme. (RJP 18:04, 21 January 2006 (UTC))[reply]
Deltas come in a multitude of plan-view shapes, as their characteristics are determined by the balance between the energy and sediment load of a separation system and the quality of the ocean. Various ways of classifying deltas have been devised. One of the more widely used schemes is based on deltaic form as it reflects controlling energy factors.translated to simple talk this means:

that its a river that flows out to sea but as it drags dirt and debris from the river bed it blocks up the exit course which makes the river flood and find or create a new river to let the water flow out of this provides a shallow swamp which provides fresh water but still allows plantlife to grow there so if your planning a resourt it would be good to let cattle go and graze in the delta. But the bad thing is that when it floods it can wipe out wildlife, Indogar villages and cattle.--Gcpeoples (talk) 08:39, 21 June 2008 (UTC)[reply]

Delta lobe switching in the Mississippi Delta, 4600 yrs BP, 3500 yrs BP, 2800 yrs BP, 1000 yrs BP, 300 yrs BP, 500 yrs BP, current
If it's put in the article, some sort of explanation or legend would be good, attached is one possibility. The image shows how the main channel has switched directions every couple thousand years, due to the reasons RJP described, and how it builds up the majority of its deposits in first one lobe, then another... --Interiot 21:21, 21 January 2006 (UTC)[reply]

Proposed merger with Outfall

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This seems a strange idea. The two have very little in common. It is true that a River delta could be called an outfall but so could an Estuary. It is clear that the Outfall article, though still short, is developing away from any connection with a natural river mouth. (RJP 22:00, 14 January 2006 (UTC))[reply]


I agree with the comment above. Although they are related with each other, they are connected very loosely. Why would anyone want to merge them anyway? --—Preceding unsigned comment added by 86.17.147.38 (talkcontribs)

I also agree that it shouldn't be merged, since, for instance, river delta shouldn't be merged with estuary. --Interiot 21:21, 21 January 2006 (UTC)[reply]
I also agree that it shouldn't be merged, since, for instance, river delta shouldn't be merged with estuary. 70.73.73.10 (talk) 02:48, 21 October 2022 (UTC)[reply]


Confused

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I found this article a little confusing. Right at the start it states that a delta is a triangular land formation. If you look at the examples or read the discusion it becomes clear that there are two types of river delta, one charachterised by the delta shape and one more like the Mississippi. I am still not clear what kind of river delta the mississppi is but the article doesn't really warn me that there is a distinction. Furthermore the first paragraph directs me to estuaries where I learn that river deltas and liman form towards non tidal seas but the list of deltas here includes some that flow into tidal seas (I think anyway the gangees flows into the indian ocean which is tidal as far as I know). I am in no way a geographer and am really not confident to alter the article, I expect my understanding is flawed.Aach 11:19, 13 September 2006 (UTC)[reply]

The Amazon does not have a delta

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I removed the Amazon as one of the world's notable rivers with a delta as it does not in fact have one. The Amazon enters the Atlantic Ocean in an enormous estuary; it does not show the deposition of sediment and splitting into distributaries characteristic of a delta.

Here is a quote from the article about the Amazon:

'The bore is the reason the Amazon does not have a delta; the ocean rapidly carries away the vast volume of silt carried by the Amazon, making it impossible for a delta to grow. It also has a very large tide sometimes reaching 20 feet.'

Booshank 13:23, 12 October 2006 (UTC)[reply]

The Amazon does have a delta, it is referred to as a "subaqueous" Delta, because it is submerged under the water surface. See, for example:

Measurements in the bottom boundary layer on the Amazon subaqueous delta Cacchione, DA; Drake, DE; Kayen, RW; Sternberg, RW; Kineke, GC; Tate, GB Marine Geology [MAR. GEOL.]. Vol. 125, no. 3-4, pp. 235-257. 1995.

types of deltas

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Bold text i need the differntbtypes of deltas along with diagrams, for my geography home work. can i get some help?? —The preceding unsigned comment was added by 72.252.26.43 (talk) 18:07, 5 January 2007 (UTC).[reply]

Similarity with Alluvial fan

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Can anyone tell me what the difference between a River delta and Alluvial fan is? If there is not a difference then perhaps the two articles should be merged? --Daleh T 07:51, 2 October 2007 (UTC)[reply]

Really really late reply: an alluvial fan is a steep, coarse-grained, often debris-flow and flash flood dominated landform. Deltas have a shallow surface slope, and are fine-grained. Deltas also always extend into bodies of water; alluvial fans do not necessarily terminate in water bodies, and when they do, they are called alluvial fan deltas. Awickert (talk) 18:57, 6 December 2008 (UTC)[reply]

The article's section on Inland Deltas includes the Okavango, which with this definition would be an alluvial fan. If that is the case, that reference needs to be deleted, as well as the reference to "flat arid areas" in the top of the article.

not enough information about the delta

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Delta top channels Mid-channel bars Selective transport of different grain sizes Channel switching (avulsion) Channel bank erosion Creation of floodplain terraces

this article does not contain enough information

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i found the main overview of the article a little confusing. i would have appreciated it a lot more if i got a good overview of what a delta is (which is all i am looking for) by simply reading a well phrased few sentences. the above is not mention much at all.

personally i would have expected the above list to be clearly mentioned in the article. —Preceding unsigned comment added by 129.215.57.41 (talk) 13:32, 5 March 2008 (UTC)[reply]

Notable deltas

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Why are the Truckee and Carson rivers listed as "rivers with notable deltas"? Even if these rivers has deltas, they can hardly be compared to such rivers as the Nile, Mississipi and/or Ganges. All wikipedians who are not familiar with the geography of the American mid-west has probably never heard of the Truckee nor Carson rivers, so including these rivers in the list of rivers with notable deltas seems a bit strange. Besides, the Wikipedia articles on the Truckee and Carson don't mention the existence of a delta at all. DaMatriX (talk) 16:10, 7 January 2009 (UTC)[reply]

I totally agree and felt the same way when I read it. I will delete the references for us.

Tags

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I searched Delta and couldn't find this, had to search "River Delta" —Preceding unsigned comment added by Snazzyy (talkcontribs) 01:25, 10 February 2009 (UTC)[reply]

It's listed on the delta disambig page; so many meanings for delta that I'm afraid river delta is the most abstract we can do here. Awickert (talk) 21:43, 19 February 2009 (UTC)[reply]

Hudson River

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I've heard the area around the mouth of the Hudson River called an estuary. It seems to me that the situation is a bit more complicated than simply "delta vs. estuary" (even without the human settlement on top of it). Apparently, the glaciers started it by bulldozing many of the valleys and much of the land - and then coming to a halt in this area. When they melted, the area flooded. However, rivers, tides, etc. kept up the act of depositing sediments. So, by the time the Dutch showed up, we have not only the hills expected of glacial moraines, but we also have plenty of sediments trailing them and a wad of islands (Manhattan, which is an island partly because of a sort of canyon between it and the Bronx, and whose geography may have more to do with glaciers than sediment, but has some sediment on its sides and southern end; Wards Island, Randalls Island, Coney Island, parts of Long Island, Liberty Island, Governors Island, etc.) Humans complicated things by flattening some pieces of land and landfilling in other areas. In addition, there are plenty of marshes and former marshland in the area, and there's also Sandy Hook. So what exactly is this creature, a delta, a fjord, just an estuary? 68.36.120.7 (talk) 16:46, 3 January 2011 (UTC)[reply]

Types of deltas

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The article mentions that deltas are classified according to the dominant water force on them: river, tidal, and wave. However only the tidal and wave types are discussed under the section distinguishing the types. Why no mention at all of this elusive third category? 68.227.164.229 (talk) 00:12, 16 January 2013 (UTC)[reply]

Confusing map and legend

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The "Lower Mississippi River land loss over time" map has some issues:

The legend is not consistent (changing from actual year to "x years ago"), does not follow chronological order, and matching its 5 shades of gray with the map is next to impossible. On the plus side, this map has made the article famous on Twitter's @depthsofwiki ("what is going on with this map legend"). UpDater (talk) 13:56, 24 July 2022 (UTC)[reply]

I would not oppose just removing it. --Kent G. Budge (talk) 15:41, 24 July 2022 (UTC)[reply]
OK, done.
A shame that @depthsofwiki fans will be disappointed when they try to find this famous map... UpDater (talk) 19:20, 24 July 2022 (UTC)[reply]

Usefulness of Photos

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Without explanatory captions, the first two photos are not helpful. I cannot even identify the triangular shape referred to in the first photo. WmDKing (talk) 10:35, 12 January 2024 (UTC)[reply]