Talk:Sandfall

Afd result - redirect
Looks like the afd ended with consensus to redirect ... somewhere. Problem now is where. Sand rather obviously falls down the lee side of a dune ... so redirect to a relevant section of dune. Sand also cascades down the sides of submarine canyons or escarpments as illustrated by the Cabo San Lucas video and supported in the Deltaic and Shallow Marine Deposits reference (on p. 104 thru Amazon search) although in the "sand falls" two word form. (note the book is not by G.C. Amstutz - who was an ore deposit specialist) Seems the concept of flowing sand should be covered in both the sand dune/windblown and the submarine cliff or canyon water borne contexts. So ... how to determine the best target here? as one redirect can't go to two articles. Vsmith (talk) 20:35, 23 March 2013 (UTC)
 * No, this was touched on - Sand does NOT "rather obviously fall down the lee side of a dune" - it slips or slides. A fall only occurs where the sand flows over a hard edge and then falls free - a cataract being a chain of such free falls. Paul venter (talk) 06:21, 26 March 2013 (UTC)
 * Other than your say so, do we have any references in reliable sources supporting that definition? Pburka (talk) 11:45, 26 March 2013 (UTC)
 * I think a request of that sort falls squarely under WP:BLUE Paul venter (talk) 14:18, 28 March 2013 (UTC)
 * First, WP:BLUE is not policy. It's an essay. Secondly, even if it were policy, the reliable sources we have seem to contradict your claim. For example, we have a geological dictionary which says that a sandfall is a slipface. It's neither common sense nor general knowledge that sandfalls (whatever they are) are like waterfalls. If the definition is as well known as the colour of the sky, then it should be simple to find some reliable sources supporting that. Pburka (talk) 03:23, 1 April 2013 (UTC)
 * Sandfall as used in the article describes a dynamic process - 'sandfall' as described by the dictionary you cite equates it with the feature known as a slipface, something which patently it is not. If the dictionary had gone on to give a source or to expand its description, it might enjoy more credibility. WP:BLUE is an essay which advocates the use of more common sense, something which would not be out of place here. The comment hereafter seems to think the concept of sand falling over a precipice to be 'rather obvious'. Paul venter (talk) 19:31, 1 April 2013 (UTC)
 * Of course sand falls. There's no question about that, and we don't need a reference for it. However I suggest that there is no dynamic process called "sand fall": there are slipfaces, sometimes called sandfalls, and there is a site in Cabo San Lucas which has been called a sand fall. Can you provide any references in reliable sources that there is a dynamic process called sand fall, that it resembles a waterfall, and that it is found in dry, desert conditions? Can you provide any references in reliable sources that these things exist in submarine environments, other than the example in Cabo? Pburka (talk) 00:05, 2 April 2013 (UTC)
 * Do some digging around on your own - you're not obliged to place citation tags on everything I write. If you're really interested in improving WP then do some work, instead of following the easy option of being critical of everything. Paul venter (talk) 10:47, 3 April 2013 (UTC)
 * Rather obvious that sand or any sediment carried over a precipice by wind or water will "fall" or flow down the lee side. So how is it notable for a stand alone article. Should be discussed in the Cabo San Lucas article (don't see any mention there) and mentioned in other subjects involving sand/sediment carried over a precipice. Is there any ref supporting the Antelope Canyon bit? Yes sand blown over the edge of a slot canyon will fall - but sorta "so what". WP:RS needed there. Vsmith (talk) 13:07, 26 March 2013 (UTC)
 * I suppose it's sorta obvious that water going over a precipice will also fall - do we trash all waterfall articles as 'obvious'?. Really a specious argument! Paul venter (talk) 14:16, 28 March 2013 (UTC)
 * Sorry about my error with Amstutz (Msrasnw (talk) 00:16, 24 March 2013 (UTC))

Dills entry in a Encyclopedia of Oceanography and other(s)
This reference:
 * Dill, R. F. "Sand flows and sand falls." Encyclopedia of Oceanography: New York, Rheinhold (1966): 763-765.- which I have only seen in Google Scholar seems to imply a standalone article might be possible. As the redirect looks tricky (Msrasnw (talk) 00:15, 24 March 2013 (UTC))


 * This ref (I am not sure of the citation) - but is the 4th in tis GS search Manual, I. "A working party of seven experts." Ocean Industry 6.4 (1971). which one can read a pdf on GS seems to have enough on the San Lucas Canyon phenomenon. "one of nature's strangest and most increadible actions, the Underwater Sandfalls."  (Msrasnw (talk) 00:27, 24 March 2013 (UTC))

Some references for films and "discovery" of underwater sandfalls
There seem web sources (but not ones that seem easily citable) indicating J Cousteau found the Cabo San Lucas sand fall/sandfalls in the 70s but these refs seem to predate that.

The Library at UC San Diego has the following films in its collection and they are listed here:. was and is an important geological process".
 * Rivers of Sand 1959 Scientific Diving Consultants, in cooperation with Scripps Institution of Oceanography. and it "records the story of the discovery of underwater sand falls in the Cape San Lucas submarine canyon, Baja, California. The film includes aerial shots of Cape San Lucas area, outline of the submarine canyon, beach shots, and underwater shots of an old wreck, fish, sand falls and flow. It was filmed and produced by Scientific Diving Consultants, a group of three divers associated with the Scripps Institution of Oceanography; Conrad Limbaugh, Wheeler North and James Stewart." ..."The sandfall

And Should or could these be included. (Msrasnw (talk) 12:48, 26 March 2013 (UTC))
 * Underwater Wonders 1959 Scientific Diving Consultants in cooperation with Scripps Institution of Oceanography. Photography: Ron Church, Conrad Limbaugh, Wheeler North, James Stewart. Additional footage: Bev Morgan. Written: Ray Sperry. Narrated: Phil Chambers. Edited: Ron Church. "The film shows and discusses what divers see underwater, showing them swimming and carrying cameras. Footage includes a sandfall at Cape San Lucas, Baja California, showing an underwater “river of sand.”"


 * Would support the addition of sourced material to the Cabo San Lucas article which perhaps needs a section on the phenomena. This could then be redirected there perhaps - and/or add relevant stuff to Submarine canyon. Vsmith (talk) 13:13, 26 March 2013 (UTC)
 * I'd also support a merge and redirect to Cabo San Lucas. Pburka (talk) 00:15, 2 April 2013 (UTC)

Antelope Canyon photo
Paul_venter added a photograph as a reference for the claim that "sand falls" occur in Antelope Canyon. Photos are generally not reliable sources, and this photos illustrates one reason why. The description of the photo indicates that the photo was staged. The photographer poured sand on the wall to get the effect. I've removed the reference. Pburka (talk) 00:14, 2 April 2013 (UTC)
 * Good for you! Paul venter (talk) 12:26, 3 April 2013 (UTC)


 * And then, curiously, he removed the citation needed tag without providing a new reference, instead suggesting it was someone else's duty to provide the ref. Well, how are you to know it's needed without the tag present to alert you to that fact? This very much seemed like an edit aimed at making a point. Rkitko (talk) 03:17, 4 April 2013 (UTC)


 * As I wrote elsewhere - there are dozens of photos of Antelope Canyon (not staged) in which falling sand may be seen. Only some editors would feel it necessary to query that the process occurs in Antelope Canyon, and those same editors would not feel the slightest obligation to do any spadework themselves, but would rather choose the avenue of complacent and supercilious criticism. Paul venter (talk) 07:43, 4 April 2013 (UTC)
 * Please read WP:RS. A photo in a commercial gallery is not a reliable source. Vsmith (talk) 10:28, 4 April 2013 (UTC)
 * Strange that WP:RS doesn't mention 'photo', or 'image' or 'gallery'. Did you suck this from your thumb? Paul venter (talk) 10:30, 6 April 2013 (UTC)
 * WP:RS says "Articles should be based on reliable, third-party, published sources with a reputation for fact-checking and accuracy." It is common sense (WP:BLUE) that commercial image galleries don't meet these criteria. WP:RS enumerates reliable sources. The very absence of photos from this policy is evidence that they are not, and cannot, be reliable sources. Pburka (talk) 15:29, 6 April 2013 (UTC)
 * That is really poor logic Paul venter (talk) 08:05, 10 April 2013 (UTC)
 * Photos, with proper provenance, can be reliable sources, the problem is not with photos per se but with commercial image galleries. --Bejnar (talk) 16:07, 7 April 2013 (UTC)


 * The photo was not intended as a source - the text was. What exactly are you querying? Do you honestly have doubts about the occurrence of sandfalls in Antelope Canyon? My impression is that like Rkitko you are simply trying to be as difficult as possible - try some contributing of your own instead of wasting your energy on pointless criticism. Also read this and try figuring out which category you fall in. Paul venter (talk) 12:12, 4 April 2013 (UTC)
 * The "text" describing a photo in a commercial website also fails WP:RS. Please restrict your comments to the content and avoid commenting on your fellow editors, thank you. Vsmith (talk) 13:02, 4 April 2013 (UTC)
 * It is unfortunate that in this matter some of my fellow editors are the problem, and are using this article to play political games that have nothing to do with improving WP. Paul venter (talk) 06:39, 5 April 2013 (UTC)
 * Paul: I do have doubts about the occurrence of sandfalls in Antelope Canyon. I believe that sometimes sand is blown off of ledges there, but I don't believe that it behaves like a waterfall (i.e. it is episodic, not continuous or seasonal), and I don't believe that these occurrences are properly called sandfall. You've introduced these claims to the article and it is your responsibility to provide references in reliable sources to support them. Pburka (talk) 03:05, 5 April 2013 (UTC)
 * No claims are made explicitly in the article about the phenomenon's being episodic, seasonal or continuous. Comparing it with a waterfall, though, does imply that it shares some characteristics, and indeed it does - waterfalls may be episodic, continuous or seasonal. This is common knowledge WP:BLUE Paul venter (talk) 06:59, 5 April 2013 (UTC)

Sandfalls/sandfalls
Searching on the web for this term there seem to me several different things that are refered to as sandfalls: the dictionary definition - slip face on dunes, the much photographed dry canyon sandfalls (though no proper ref), the underwater phenomena and then reproductions of this in aquaria (also no proper ref). I feel our article might usefully mention the ambiguity and list these. I cannot see how a single redirect could do this. (Msrasnw (talk) 07:26, 2 April 2013 (UTC))

I have added a ref and note on the claimed ubiquity of the underwater sandfall phenomena. Hope is OK.

Is sandfall an eg of grain fall/grainfall and this might be a better or more technical name? There seem more sources on this and this relates more closely with the dictionary definition and then our sandfalls that look like waterfalls are nice or special egs of this?

The Carter ref includes the submarine sandfalls under the Grain-fall heading and has a nice general definiation of grain-fall. (Msrasnw (talk) 10:13, 2 April 2013 (UTC))

Grain-fall "When sediment of any grain-size is transported to the edge of a slope considerably in excess of its stable angle of repose, the individual grains pass into free-fall under the direct influence of gravity". Carter, RM (1975) p. 160

Definitions
I think we need to include something about formal defs. eg: Bucksch (1996) defines a sandfall to be "The steeply sloping surface on the lee side of a dune standing at or near the angle of repose of loose sand and advancing downwind by a succession of slides wherever that angle is exceeded" Bucksch, Herbert  (1996) Dictionary geotechnical engineering: English German." (1996): 61. (Msrasnw (talk) 11:10, 3 April 2013 (UTC))
 * I really don't know what this dictionary compiler was thinking - he defines the sandfall in terms of "a succession of slides". Did the contradiction not occur to him? Paul venter (talk) 12:33, 3 April 2013 (UTC)
 * I think despite, your worries about a possible contradictiopn, sandfall (and grainfall) is used this way to label a zone on the leeside of a dune. By the way the article below - Turner and Makhlouf has some pictures in - but they are not as nice as the Antelope Canyon one's where they have the sandfalls falling further out from a face due to some overhang. Best wishes (Msrasnw (talk) 13:01, 3 April 2013 (UTC))

"Sandfalls, as defined here, are dry sandflows cascading down the escarpment face, where the grain concentration decreases dramatically and the streaming component of stress greatly exceeds the collisional component." Turner, Brian R. and Issa Makhlouf(2002) Recent colluvial sedimentation in Jordan: fans evolving into sand ramps, Sedimentology Volume 49, Issue 6, December, Pages: 1283–1298

Another meaning
Sandfall is also used to describe sand falling like rain - there are sources for this in reports for Iceland (Thorarinsson S (1967) The eruptions of Hekla in historical times. In: Einarsson T, Kjartansson G, Thorarinsson S (eds) The eruption of Hekla 1947–48 I. Societas Scientiarum Islandica, Reykjavík, pp 1–177) and for China (Liu, Zhao-Ming (2012) The Analysis of Historical Records of Chinese Ancient Dustfall and Sandfall Events) (Msrasnw (talk) 11:23, 4 April 2013 (UTC))