Search found 27 matches

by idawg
Sun May 31, 2020 11:41 am
Forum: General Geophysics and Geoscience
Topic: Guess geophysics terms
Replies: 9
Views: 1113

Re: Guess geophysics terms

First one, free air?
by idawg
Sun May 31, 2020 11:08 am
Forum: Near Surface Geophysics
Topic: Guess what's in the GPR profile
Replies: 11
Views: 1737

Re: Guess what's in the GPR profile

For the first anomaly, it looks like the soils above it are different from its surroundings. There must be some digging or excavation there before.
by idawg
Mon Jun 09, 2014 3:59 pm
Forum: Near Surface Geophysics
Topic: GPR for railways
Replies: 3
Views: 1021

Re: GPR for railways

viewtopic.php?f=2&t=2003

It sounds like you can contact GSSI.
by idawg
Thu Jan 31, 2013 11:09 pm
Forum: Near Surface Geophysics
Topic: Engineering Geophysics for Rail Engineers
Replies: 8
Views: 10449

Re: Engineering Geophysics for Rail Engineers

It's all about name selling :D
by idawg
Thu Jan 31, 2013 11:07 pm
Forum: Near Surface Geophysics
Topic: National GPR Service Inc. Announces New Brand Licensing Program
Replies: 3
Views: 4340

Re: National GPR Service Inc. Announces New Brand Licensing Program

I don't know exactly how rules are played with all these licensing things, but as far as I know, brand licensing is very liberal. Any company can do this. Basically it's about selling their names, and you don't need any official recoginition. In fact, they are their own "official" while doing these ...
by idawg
Fri Jan 25, 2013 9:55 am
Forum: Near Surface Geophysics
Topic: Dual frequency ground penetrating radar for underground utility locating
Replies: 37
Views: 18911

Re: Dual frequency ground penetrating radar for underground utility locating

Thanks for the links! What have you used them for so far? I am trying to decide whether I should get one and what system I should choose.
by idawg
Wed Jan 16, 2013 12:31 pm
Forum: Near Surface Geophysics
Topic: Dual frequency ground penetrating radar for underground utility locating
Replies: 37
Views: 18911

Re: Dual frequency ground penetrating radar for underground utility locating

It looks like it's really fun. Is it much more expensive than regular utility locating GPRs?
by idawg
Sat Jan 05, 2013 5:00 pm
Forum: Near Surface Geophysics
Topic: Dual frequency ground penetrating radar for underground utility locating
Replies: 37
Views: 18911

Dual frequency ground penetrating radar for underground utility locating

How do you guys feel about using dual frequency ground penetrating radar for underground utility locating? Is it necessary?
by idawg
Tue Jun 12, 2012 12:04 pm
Forum: Near Surface Geophysics
Topic: Type of GPR antennas for underground utility locating
Replies: 3
Views: 4307

Re: Type of GPR antennas for underground utility locating

So the easy locator from Mala uses dipole antennas?
by idawg
Sun Jun 10, 2012 4:22 pm
Forum: Near Surface Geophysics
Topic: Type of GPR antennas for underground utility locating
Replies: 3
Views: 4307

Type of GPR antennas for underground utility locating

I heard there are different types of GPR antennas such as step-frequency and horn antennas. What are the main differences among them and what's the best type of antennas for underground utility locating? Thanks!
by idawg
Fri Mar 02, 2012 2:05 pm
Forum: Near Surface Geophysics
Topic: Acoustic pipe locator
Replies: 1
Views: 3245

Re: Acoustic pipe locator

Radiodetection RD500, best acoustic tool I have ever used.
by idawg
Sun Feb 26, 2012 3:28 pm
Forum: Near Surface Geophysics
Topic: methods to mark underground power lines
Replies: 4
Views: 4199

Re: methods to mark underground power lines

They can be shallower than 3 feet especially where it comes down the pole or close to your house, you need to be really carefully while digging.
by idawg
Sat Feb 25, 2012 7:34 am
Forum: Near Surface Geophysics
Topic: methods to mark underground power lines
Replies: 4
Views: 4199

Re: methods to mark underground power lines

The cable is generally located with a cable locating unit. It's usually very accurate for residential houses as along as the utility locator does his diligence.
by idawg
Fri Feb 24, 2012 8:16 pm
Forum: Near Surface Geophysics
Topic: Clay pipe locator
Replies: 3
Views: 4000

Re: Clay pipe locator

Most of these clay or ceramic pipes are storm drains, you should be able to see the openings such as catch basins and manholes. Usually they are pretty straight between openings.
by idawg
Wed Feb 15, 2012 4:59 pm
Forum: Near Surface Geophysics
Topic: Concrete X Ray V.S. GPR
Replies: 6
Views: 4777

Re: Concrete X Ray V.S. GPR

I didn't know concrete x ray services really exist. I thought it's only a sort of expression for concrete GPR...
by idawg
Mon Feb 13, 2012 8:55 am
Forum: Near Surface Geophysics
Topic: How to locate buried fiber optic cables
Replies: 14
Views: 29634

Re: How to locate buried fiber optic cables

They should install trace wires as they did for the gas pipes. Breaking fiber optic cables would not cause immediate danger, but could cause severe financial damages. Breaking one of the fiber optic cables in Verizon switch centers could cost millions of dollars.
by idawg
Sun Mar 06, 2011 11:16 am
Forum: Near Surface Geophysics
Topic: GPR 400MHZ for fiber optic
Replies: 21
Views: 8778

Re: GPR 400MHZ for fiber optic

Fiber optic cables are usually wrapped up with rubber and plastic layers. What you see in the GPR transects are mostly likely from the outside layers instead of the fiber optic cables themselves. Yeah, I agree that the their signals would look like those from PVC pipes.
by idawg
Sat Jul 24, 2010 5:39 pm
Forum: General Geophysics and Geoscience
Topic: Geophysical courses
Replies: 18
Views: 24463

Re: Geophysical courses

Which universities have the best geophysics programs? I want to check courses they offer and what textbooks they usually use.
by idawg
Sun Jul 18, 2010 10:05 am
Forum: General Geophysics and Geoscience
Topic: Geophysical courses
Replies: 18
Views: 24463

Re: Geophysical courses

Thanks, Guys! I only have a high school diploma. Do you get some trainings in the computer skills in these courses? I am tired of doing utility locating everyday. I want to do those cool things like EM mapping, landfill delineation, seismic surveys and other geophysical surveys. I have been assistin...
by idawg
Sat Jul 17, 2010 8:18 am
Forum: General Geophysics and Geoscience
Topic: Geophysical courses
Replies: 18
Views: 24463

Re: Geophysical courses

I want to be a geophysical technician instead of utility locator. I want to learn some basic theories about geophysics and maybe something about georadar and electromagnetic.
by idawg
Fri Jul 16, 2010 1:59 pm
Forum: General Geophysics and Geoscience
Topic: Geophysical courses
Replies: 18
Views: 24463

Geophysical courses

What are the typical courses in geophysics? I want to register some classes in the local community college. Please advise, thank you!
by idawg
Wed Feb 24, 2010 9:45 pm
Forum: Near Surface Geophysics
Topic: Subsurface utility locating
Replies: 10
Views: 7449

Re: Subsurface utility locating

I don't think TW-6 and FX3 work well in subsurface utility locating. They might help to find some pipes which you would miss otherwise, but this kind of situations are rare and they are waste of time in most cases.