Talk:Ground-penetrating radar

Question

I want to know atmosphere effect on gpr radars

What do you mean by the atmospheric effect? The radar pulses are sent into the ground. However, if the transmitter antenna is not shielded it emits radiation everywhere. Thus, nearby buildings and trees also cause reflections that may be seen in the measured data. Is this what you mean or am I missing something?

Most GPRs have an antenna in contact with the ground. No atmospherics. Dominick ^(TALK) 12:53, 14 November 2006 (UTC)

Sometimes you unintentionally get nice images of overhead power-lines where you think you are looking at the ground. The antennae try to have contact with the ground, however, it is difficult to focus this range of frequency (even with shielding), and power-lines provide lots of noise.+mwtoews 09:40, 20 December 2006 (UTC)

This is mentioned in the Richard Kregeg wiki article. There GPR is dismissed by historians ( what that means I am unsure of ) because it didn't find ground disturbance - of course this was at Treblinka ( really messed up a good story ). Is GPR reliable - if it finds that the ground has not been disturbed does it mean that the ground may have been massively disturbed or not. How would a 'historian" know the difference. I believe I recently saw GPR used in Mongolia? on a National Geographic archaeology show - they seemed to find it reliable but maybe it doesn't work well in Poland159.105.80.219 14:20, 5 January 2007 (UTC)

I don't know anything about the conditions at the site in Poland, but GPR is not effective in some soils, particularly those containing clay. This is well known, and experienced practitioners will use other geophysical methods where conditions are not appropriate for GPR. It is all too common, however, to see it applied inappropriately. Tapatio 22:57, 7 April 2007 (UTC)

Locate uranium deposits from space?

It is well-bandied-about that at current prices the world has 50 years of uranium deposits. (Note: fuel cost is very small in nuclear power plants, and price increases could easily be absorbed.) Is it possible to locate uranium deposits from space? Are there specific frequencies which Uranium-235 and Uranium-238 would reflect? Simesa 23:11, 5 July 2006 (UTC)

A radar of all types give the instrument an measure of the reflection coefficient. It would depends on specific ores and specific substrata. Usually buried objects can be found only a short distance underground. Specifically a particular element may resonate in a native ore at a particular frequency. Frankly when people say we are running out of element X, that usually precedes the discovery of a rich source or it starts the sales pitch for an investment scheme. Uranium in sea water and in undersea deposits have never ben exploited, so I would say we have many centuries of supply. Dominick ^(TALK) 12:53, 14 November 2006 (UTC)

Better illustration?

The figure used as an illustration in this article really isn't all that illustrative, as it does not show any distinctive refections. I have access to lots of GPR data, and could contribute something showing interesting subsurface features. Tapatio 17:35, 8 June 2007 (UTC)

I agree, and I've briefly looked for something through the USGS websites (because it is public domain), but haven't done a serious search .. you could try to help out by looking on their websites for something more interesting. +mwtoews 17:53, 8 June 2007 (UTC)

How about this (from my own work)?Tapatio 14:25, 11 June 2007 (UTC)

Yes, that is certainly improved, since there is something to see. I'll replace the first example photo.+mwtoews 16:44, 11 June 2007 (UTC)

I'm glad someone caught the parabolic vs. hyperbolic error. It was careless acquiescence to the spell check on my part. Tapatio 05:15, 14 June 2007 (UTC)

How about an illustration of GPR in use? Tapatio 17:34, 5 July 2007 (UTC)

Spam

It seems like the external links section is almost all spam. It has been tagged with a spam warning, but nobody seems to want to fix it. What criteria might we apply in deciding what is spam and what is not?

Keep

- sites that provide more detail/examples--CheMechanical 16:38, 31 July 2007 (UTC)
- sites with proprietary GPR techniques or equipment--CheMechanical 16:38, 31 July 2007 (UTC)

I would be inclined to discard commercial sites with proprietary GPR techniques or equipment. They are basically advertising their products or services. If such sites represent the mainstream of GPR practice or instrumentation, this should be treated in the body of the article. If they represent important advances, these could be mentioned in an appropriate section as well. Tapatio 20:49, 9 August 2007 (UTC)

Discard/Remove

- all others--CheMechanical 16:38, 31 July 2007 (UTC)

I did it

I have deleted the ugliest of the spam from the external links. I don't think any of them could be justified under wikipedia policy (see Wikipedia:External links, particularly Links normally to be avoided). I think that the links in the "Examples of GPR radargrams" section are a bit dodgy also, but they fullfill a need that is not currently met by the article. It would be nice to see a couple more examples of different applications and presentations within the article, then get rid of these links. Tapatio 15:09, 16 August 2007 (UTC)

-I work for a leading nondestructive testing firm, and I believe there is benefit in including my company website in the external links. Our project portfolio illustrates many different radar applications in infrastructure. There are also various images that show GPR processing and analysis. Is this appropriate for the external links section? — Preceding unsigned comment added by Evan.guarino (talk • contribs) 19:12, 18 August 2011 (UTC)

It would be more appropriate to edit this article. It needs work, and expert contributions would be welcome, as would graphic examples (radargrams or photos) of different applications. Tapatio (talk) 21:11, 18 August 2011 (UTC)

Time slicing

In archaeology it has become the norm to view GPR data as time-slice plots of multiple lines of data, as well as vertical sections of individual lines. Is time slicing common enough in other disciplines to be discussed here? Tapatio 17:34, 5 July 2007 (UTC)

Inventor and date?

Can we get a quick blurb on who invented it and when it was invented? I wanted to find out if it existed back in 1980 to answer someone's question elsewhere, but I couldn't find that information here. I found information on one site that said it was invented "in the 1970's" for the military, but nothing more specific or useful as a citation. -- HiEv 09:34, 30 September 2007 (UTC)

GPR has been used earlier than the 1970s. In September 1976, I was on a Coast Guard C-130 (USCG 1351) flight where we had a NASA crew, mini-computer, and a Side Looking Radar system. We used this to fly Alaska's North Slope and over the (North) Polar Ice Cap. This Radar system provided the thickness of: sea ice, flow ice and permafrost. We flew tracks that went East from Point Barrow to Canada's Yukon Territory, and West to Cape Lisburne. DeanRB 22:02, 24 October 2007 (UTC) DeanRB

Limitations

The paragraph enumerating the limitations of GPR (The limitations of GPR are many in this current day and age...) seems a bit out of place in the introductory paragraph. Perhaps this subject can be spun off into its own heading. Tapatio (talk) 15:25, 22 May 2008 (UTC)

It should certainly be in its own section (below "Applications"), and I was going to move and reword it when it was added, but I haven't ... so dive in! (It also needs some references). +mt 16:38, 22 May 2008 (UTC)

I started a rudimentary section an limitations. I don't have specific references, but I think it is all common knowledge to people in the field and non-controversial (previously it had some POV issues). Feel free to edit, expand, or expurgate. Tapatio (talk) 18:44, 22 May 2008 (UTC)

Question

Can GPR be used effectively to locate buried facitlites such as buried pipes (4" to say 12"), or buried electrical cable with any kind of confidence? —Preceding unsigned comment added by 207.229.13.65 (talk) 20:32, 19 March 2008 (UTC)

It often used for that purpose. It can be very successful when used appropriately and under favorable conditions. Tapatio (talk) 01:05, 13 July 2008 (UTC)

Spam revisited

This page has previously been purged of links to commercial websites of practitioners and manufacturers (see above). Lets keep it that way. See Links normally to be avoided and Advertising and conflicts of interest. Manufacturers and practitoners are welcome to make improvements to the content of the article, however. Tapatio (talk) 14:13, 24 July 2008 (UTC)

Future Developments?

Some Russians were trying to develop GPR to work better in clay soils by increasing the transmitter power. [1] Has anything come from this? In many regions, they do not currently use GPR due to limitations of the soil.Landroo (talk) 18:46, 19 January 2009 (UTC)

Merger proposal

I propose that the artical Ground penetrating radar survey (archaeology) be merged into the article for Ground penetrating radar as the principle is the same, the archaeological use of the technique is simply that, and does not really justify it's own article. The page Ground penetrating radar survey (archaeology) could then redirect to the main article. Trevor Marron (talk) 15:35, 7 June 2009 (UTC)

Support. I'm not sure what exactly needs to be merged. Maybe the Applications section should be elaborated, and the references from the other article can be pulled over? +mt 20:52, 7 June 2009 (UTC)

Ambivalent. As it stands I would agree, but a fuller treatment of the subject would merit its own article. I had originally intended to elaborate upon the archaeological applications for GPR, along with separate articles on resistance and magnetic surveys in archaeology. Unfortunately, My work schedule has kept me from devoting any time to it. Nobody else has stepped up to the plate either, in spite of some initial enthusiasm from certain parties. Tapatio (talk) 02:31, 18 June 2009 (UTC)

Support one of two moves: either that suggested, or to Geophysical survey (archaeology). Awickert (talk) 15:28, 2 September 2009 (UTC)

Question

I want to know what frequenvies gpr radar uses, maybe a few more technical details. Also, what are the pulse energy ranges? Radzewicz (talk) 08:35, 31 August 2009 (UTC)

Add to the article: Explain why they're not used to discover IEDs.

In Iraq & Afghanistan, why do we still fall victim to embedded IEDs? Why can't GPR discover them before they detonate?

In the spirit of being allowed only to talk about how to improve the article, would anyone be so kind as to add the explanation onto it? Thanks. --70.179.174.101 (talk) 01:17, 7 January 2012 (UTC)

GPR is among the technologies used for IED/mine/UXO detection, but it's not a cure-all for IEDs:

• IED composition and detection environments are very variable, and no single instrument can be unversally effective.
• Several types of sensors might be used in different circumstances, but I suspect GPR is probably not among the most useful.
• Instrumental detection - whether by GPR, metal detector, or whatever - is time-consuming and not always effective (false positives; failure to detect).
• Instrumental detection may be too slow to be compatible with military movement, and too open to enemy fire and other security risks.
• Other means, including RF jamming, visual detection, and procedural methods have been adopted as the most pragmatic counter-measures.

I don't think this really needs to be discussed on the GPR page. Maybe on the IED page.Tapatio (talk) 19:24, 9 January 2012 (UTC)

Who's copying who?

It seems to me that a big section of this article is ripped straight from one website: http://www.jetsilverventures.com/ground-penetrating-radar-2/ , particularly the sections of applications, three-dimensional imaging, limitations and similar technologies. If this is the case, then this article needs a rewrite. Nwhit (talk) 16:06, 16 March 2012 (UTC)

If you look at old versions of this article, you can see that it has been developing gradually over several years. So it's pretty clear that the other site is copying ground-penetrating radar. This is not unusual - WP articles often have several clones on the Web. RockMagnetist (talk) 16:23, 16 March 2012 (UTC)

The other site is indeed using material lifted from Wikipedia. I wrote some of the text (for Wikipedia) and took one of the photos myself! They may certainly do that, but it really places their credibility in doubt. Tapatio (talk) 21:20, 9 October 2012 (UTC)

Merger

The recent merger of this page with Ground penetrating radar (archaeology) is fine, except that it leaves the article with an overemphasis on archaeology. I would issue a challenge to specialists in other applications to help rectify this imbalance by writing sections related to their fields. Tapatio (talk) 21:26, 9 October 2012 (UTC)

As an archaeologist working with GPR in other fields, I agree that the way the article is structured there's too much emphasis on archaeology. However, if you look at the section on archaeological uses of GPR, most of it is actually about GPR in general. I sugest moving the sections around so that the parts about general techniques are incuded with the main information and the odd sentence about archaeology not currently in the archaeology section be moved there.

Markaeologist (talk) 10:50, 14 October 2014 (UTC)

Depth of Penetration

The table of "approximate penetration" and "smallest visible object[s]" has no sources and is uncited. It also seems fantastically optimistic. In my experience, the useful penetration of 225MHz and higher frequencies in clay is effectively zero. There can be some response in the near surface, but any deeper response is too faint to pick out from amidst the noise and "ringing" effects. There do seem to be exceptional clays in which GPR can work well, but I have not encountered this. The other figures seem unrealistic in real-world contexts as well. This table may have some theoretical basis, but not a practical one. Could the table be from some manufacturer's website, and intended to sell radar systems rather than accurately reflect practical limitations? — Preceding unsigned comment added by Tapatio (talk • contribs) 16:12, 1 July 2015 (UTC)

I think I know something about the 'exceptional' clays - I think I remember reading about Larry Conyers being surprised at getting spectacular results from some 'clay' that later turned out to be a deposit of something with the same mechanical properties as clay (eg, particle size, so it looked and behaved like clay physically) but which wasn't mineralised. In other words, it was definitely a special kind of clay and unlike 99% of clay that one might otherwise encounter, in that it didn't attenuate the signal because it wasn't particularly conductive. Not sure that helps the article much though.

Markaeologist (talk) 10:13, 14 December 2017 (UTC)

Table in 'Limitations'

Why are the standard units for this table in Imperial measurements, with metric given in brackets? First, they're not SI (accepted as standard for scientific measurement worldwide), and secondly, only 5% of the planet officially uses them.

I suggest removing the Imperial units from the table and only leaving the SI units.

But, as the table itself has no provenance, and to my eyes at least looks quite optimistic (1.8m penetration in wet clay for a 500MHz rig? Seeing a 10cm pipe at 4m?) perhaps it should just be deleted.

EDIT: I see that User:Tapatio has already posted about the optimism of this table (not the SI units though!)

Markaeologist (talk) 09:19, 12 June 2017 (UTC)

Proposal to delete table

As discussed by both myself and Tapatío the table of depth penetration in 'Limitations' is not fit for purpose. It almost certainly comes from an advertisement not a serious technical discussion of the possibilities of getting real results.

I propose to delete it and welcome any feedback on that proposal (especially any good reasons why it should stay up).

Markaeologist (talk) 11:01, 3 July 2017 (UTC)

I've deleted the table. Now about those '1ft, 3 ft, 10ft' etc measurements in the paragraph on typical transect widths. Typical, maybe, for the 5% of the world's population that measures things in 'bits of dead French kings', but not for the 95% of the population that uses the metric system. So I propose changing the units to mm and m.

The two last paragraphs of 'Limitations' are just a mess anyway though as 1-they don't really have anything to do with limitations of GPR as such and 2-they're unsourced anyway. Along with improving their accuracy, relevance and reliability, I suggest we think about where they fit best.

Markaeologist (talk) 07:15, 15 August 2017 (UTC)

Proposal for 'Limitations' section

In light of the fact that GPR is dependant on local conditions, the US Department of Agriculture produces some excellent 'GPR Soil Suitability Maps' covering the majority of the co-terminous states and Hawaii (all states except Alaska have a map, but not all areas of every state are mapped). These maps are coloured to represent different areas as being suitable or not for using GPR, due to local soil characteristics. Is it worth mentioning these in the section on 'Liitations' as this specifically mentions soil conditions, and linking to them? The address is https://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053622 It seems the USA is leading the field here but if other maps for different jurisdictions exist or are created, we can expand the info to list other countries too. Markaeologist (talk) 10:03, 14 December 2017 (UTC)

Add a tag for Archaeology?

At present the GPR page is tagged as 'geology'. However, most of the information on the page is about Archaeology. I don't know about other countries but in the UK the majority of GPR is probably done to find utilities like water pipes and gas mains as part of building projects (eg new roads, housing developments etc) and for safety inspections. It's also used in fields as widespread as forensics and civil engineering. So is only having a 'Geology' tag on here appropriate, given that there's actually very little information about (eg) oil exploration? In terms of information 'Archaeology' would be a better tag, and some other tags might be appropriate too. Markaeologist (talk) 11:28, 15 December 2017 (UTC)

Presuming that you are referring to the WikiProject template at the top of this page, you don't need to ask here whether you can add others, Markaeologist. Just go ahead and do it if you think it is appropriate. Only if someone subsequently objects do you really need to discuss a simple and (hopefully) uncontroversial matter like this. Cordless Larry (talk) 13:02, 15 December 2017 (UTC)

OK, done, for Archaeology at least. Markaeologist (talk) 15:01, 19 December 2017 (UTC)

Is this really synonymous with ground "scanning"

I mostly write about military radars, where "ground scanning radar" refers to a very specific concept first introduced by H2S (radar). These are radars that scan the ground, typically from the air. I have not heard of "ground scanning" being used to describe ground penetrating radars, but this may be simply because I don't read the right things... So is this really a widely used term for this concept, and is it more widely used than the existing H2S-like usage? Maury Markowitz (talk) 13:07, 18 June 2022 (UTC)