Where to measure your GPR target's depth (Ground Penetrating Radar)

[@benjilee9802]

Another Great Video Dan. The Black shirt suits you too 👌👌👌 Attending your 3 Day workshop really opened our eyes to a world of GPR we knew very little about. Keep the videos coming bud.

[@Learngpr]

Benji Lee thanks so much...for the compliment and the shirt! I'm glad you guys got some helpful stuff out of the seminar. 3 days is still only the beginning. LADS and learngpr have more work to do together.

Hi Dan, thank for the sharing your knowledge. I really appreciate your channel. I understand what you said and agree it might not make huge difference measure from the first or second band. But in a completely different scenario it might not work. I'm working with 900 and 400 MHz GPR profile to investigate snow layers in Antarctica, dry snow. In some case the fuzzy zone the 3 band are much wider the some reflected layers, due to the sum of the set up GPR-sledge-windcrust-snow.

[@Learngpr]

Great example of where it makes a big difference! Thanks so much fornthe comment.

[@concretegprllc1040]

This makes a ton of sense, thank you. It's also notably counter to the default interactions in RADAN and explains some challenges we faced with inconsistencies between ground truth measurements on a recent project.

[@GeelongCableLocations]

Great video Dan and very good topic. It's interesting, I've always gone from where the colour changes, but I guess it does actually make sense that each one will be right, so long as you pick ground zero at the same point. This might be a great video to do out in the field showing an actual target. Might have to see if I can do one next time I have spare time and have the right gear on site. PS - Love the shirt mate, lol

[@Learngpr]

Geelong Cable Locations good idea about a realtime example. Thanks for the compliment on the shirt. I would love it you sent over a geelong cable locations shirt. I would rock it hard!

[@GeelongCableLocations]

Hahahah, if I had some cool looking shirts like Benji does then yes would definitely send you one. We only have the boring Hi Vis shirts, but I should really look at getting something that looks cooler. Oh well, maybe one day :)

[@Learngpr]

Geelong Cable Locations you have to make me a promise then...i get the first shirt with the geelong cable locations mascot on it. I love that guy.

[@Learngpr]

Geelong Cable Locations ps...congrats on the Storm. Just watched yesterday.

[@Josh-ch4df]

Awesome video Dan. A simple answer, to what some perceive (and arguably is) a complex phenomenon. - Josh

[@Learngpr]

JubaJosh thanks josh! Much appreciated.

[@kevinchiasson2495]

Dan, the one thing you forgot to mention was the fact you have to calibrate your velocity to your soil types prior to calculating depths, (I think that's what I mean?). AM I WRONG? Anyways, keep up the great work, I refer to your videos often, more than one man should! Keep up the great work!

[@Learngpr]

Kevin Chiasson you are 100 percent correct. I sort of made the assumption in my head that I already calculated the velocities. Great pick up. None of this video matters if those velocities are out of whack. I appreciate the comment and thanks so much for watching kevin!

[@jalthaus80]

I understand your point and I may not know the right answer but there has to be a right answer or some way to find out. If we let people choose a time-zero that is too deep then at some point there will be a chance of cutting out real targets.

[@Learngpr]

Jamie Althauser ultimately they are all the right answers when it comes to depth estimation as long as your ground surface location is consistent with your targets location as it relates to the 3 band signal. In this it is implicit that you identify a ground surface or there can never be a reference for depth. Another issue gets at why all estimates are just that, estimates. There is no exact spot to pick across all circumstances because the fuzzy zone that all antenna carry varies from frequency to frequency. Also the wavelength varies for the same frequency in different material which would change the thickness of the fuzzy zone. So it is always an estimate. Certainly the lower the frequency the more grey area in the interpretation. Thanks so much for the comment. I always appreciate your insights. Hope all is well up in ohio

[@jrglidden]

When you are giving depths of utilities, know your customer / excavator. Sometimes you may benefit from giving a slightly shallower depth. There are excavators that will think they can dig 3 feet down to a utility 3.25 feet deep. Telling them 2.75 feet only protects them and the facilities. *Not always kosher, but definitely a possible help in the right scenario.* Also could help if you are on uneven/inconsistent soils.

[@Learngpr]

Joe Glidden again some great insight. Things are so situational. Knowing your customer and giving them the information based on their behavior is a good.