
Search found 935 matches
- Fri Feb 12, 2021 6:58 pm
- Forum: General Geophysics and Geoscience
- Topic: Magma as a generator of plasma and thermonuclear fusion in the bowels of the Earth
- Replies: 5
- Views: 235
Re: Magma as a generator of plasma and thermonuclear fusion in the bowels of the Earth
You certainly got a lot of new ideas. I will certainly read them when I got time. Currently I am so busy, but good to know there are some interesting ideas out there. I used to think seismology is almost dead: we already got the general idea, we just need to fill in the details. 

- Tue Feb 02, 2021 3:22 pm
- Forum: Near Surface Geophysics
- Topic: Good devices to detect Void/graves
- Replies: 8
- Views: 455
Re: Good devices to detect Void/graves
You might be able to find a 2nd hand ground penetrating radar with that price range.
- Fri Jan 15, 2021 4:47 pm
- Forum: Near Surface Geophysics
- Topic: Archaeologists Are Just Beginning to Unearth the Mummies and Secrets of Saqqara
- Replies: 2
- Views: 346
Re: Archaeologists Are Just Beginning to Unearth the Mummies and Secrets of Saqqara
Anyone has Netflix subscription to share the thoughts about the documentary "Secrets of the Saqqara Tomb"?
- Fri Jan 15, 2021 4:45 pm
- Forum: Near Surface Geophysics
- Topic: Archaeologists Are Just Beginning to Unearth the Mummies and Secrets of Saqqara
- Replies: 2
- Views: 346
Re: Archaeologists Are Just Beginning to Unearth the Mummies and Secrets of Saqqara
Found an article about a GPR survey at Saqqara, don't know whether it's related.
https://www.tandfonline.com/doi/pdf/10. ... 20.1746891
https://www.tandfonline.com/doi/pdf/10. ... 20.1746891
- Sat Jan 02, 2021 3:29 pm
- Forum: General Geophysics and Geoscience
- Topic: Nature and Energy of Earthquakes or Seismology for Dummies
- Replies: 17
- Views: 1195
Re: Nature and Energy of Earthquakes or Seismology for Dummies
Seismologists, like brave liars, lied, and continue to lie. You want to eat, so they lie! Earthquakes are impossible to predict! And to get a piece of the pie, you just need to declare to the whole earthly world that in 100 years, somewhere there will be an earthquake. This is how everyone can make...
- Sat Jan 02, 2021 3:19 pm
- Forum: General Geophysics and Geoscience
- Topic: Water well in limestone enhance production?
- Replies: 3
- Views: 268
Re: Water well in limestone enhance production?
I guess high resistivity zones correspond to fresh water bearing zones? And interestingly these zones have relative "flat" caliper readings. Maybe these zones are plugged?
- Fri Jan 01, 2021 6:05 pm
- Forum: General Geophysics and Geoscience
- Topic: Water well in limestone enhance production?
- Replies: 3
- Views: 268
Re: Water well in limestone enhance production?
I have done some geophysical borehole loggings before, but I am curious how you define plugging the water well. I guess if you plug the well only at the bottom, then you can still do the logging?
- Fri Jan 01, 2021 6:02 pm
- Forum: General Geophysics and Geoscience
- Topic: Nature and Energy of Earthquakes or Seismology for Dummies
- Replies: 17
- Views: 1195
- Fri Jan 01, 2021 5:59 pm
- Forum: Near Surface Geophysics
- Topic: Locating a man made tunnel
- Replies: 28
- Views: 11840
Re: Locating a man made tunnel
It looks like a spammer.99thpercentile wrote: ↑Fri Jan 01, 2021 4:20 pmgopal123
Why did you retype my previous answer in your own words?
- Mon Nov 30, 2020 4:06 pm
- Forum: Near Surface Geophysics
- Topic: Facebook Severs Second Cable; Leaves Debris at Tierra Del Mar
- Replies: 1
- Views: 422
Re: Facebook Severs Second Cable; Leaves Debris at Tierra Del Mar
What do they do ERT survey for?
- Wed Nov 18, 2020 10:30 am
- Forum: Near Surface Geophysics
- Topic: Locating a man made tunnel
- Replies: 28
- Views: 11840
Re: Locating a man made tunnel
How deep was the tunnel? How big was it?
- Wed Oct 21, 2020 1:38 pm
- Forum: Near Surface Geophysics
- Topic: Passive-Seismic and the Fibonacci Sequence
- Replies: 1
- Views: 685
- Sun Oct 11, 2020 1:05 pm
- Forum: Near Surface Geophysics
- Topic: 2D Cemetery mapping with GPR
- Replies: 3
- Views: 2122
Re: 2D Cemetery mapping with GPR
The link doesn't work -> file not found.
- Wed Oct 07, 2020 6:17 pm
- Forum: Near Surface Geophysics
- Topic: UgCS GeoHammer webinar
- Replies: 2
- Views: 954
- Wed Oct 07, 2020 6:16 pm
- Forum: Near Surface Geophysics
- Topic: The fusion of the results of aerial photogrammetry, magnetic and GPR surveys
- Replies: 4
- Views: 1300
- Wed Oct 07, 2020 6:15 pm
- Forum: Near Surface Geophysics
- Topic: 10 vs 3.5 kHz SBP system for shallow water
- Replies: 2
- Views: 855
Re: 10 vs 3.5 kHz SBP system for shallow water
10KHz gives you better resolution and 3.5KHz gives you better penetration depth. I prefer 10Khz since clayey and silt sediments are more friendly than sands for penetration.
- Tue Sep 15, 2020 5:18 pm
- Forum: Near Surface Geophysics
- Topic: The fusion of the results of aerial photogrammetry, magnetic and GPR surveys
- Replies: 4
- Views: 1300
Re: The fusion of the results of aerial photogrammetry, magnetic and GPR surveys
6pm in your local time? What's your time zone?
- Sat Sep 12, 2020 12:07 pm
- Forum: Near Surface Geophysics
- Topic: a strange GPR anomaly
- Replies: 4
- Views: 1126
Re: a strange GPR anomaly
I took another look at the file. Now I realize it might be an underground wall with a slope. I think it's safe to say the mystery is mostly solved.
- Sat Sep 12, 2020 10:12 am
- Forum: Near Surface Geophysics
- Topic: Locating a man made tunnel
- Replies: 28
- Views: 11840
Re: Locating a man made tunnel
Kknq, please see a void model and its gpr data simulation below. You can see there are apparent different responses between the two sides and the middle of the void. When the void spacing (depth wise) is small, you can easily get the "ringing" effect as shown at the two sides due waves bouncing betw...
- Wed Sep 09, 2020 6:55 pm
- Forum: Near Surface Geophysics
- Topic: a strange GPR anomaly
- Replies: 4
- Views: 1126
Re: a strange GPR anomaly
I still tend to believe it might be some kind of diffraction from something close to the ground surface, but it doesn't look like any diffractions I usually see. I haven't really think it through.
- Tue Sep 08, 2020 5:47 pm
- Forum: Near Surface Geophysics
- Topic: a strange GPR anomaly
- Replies: 4
- Views: 1126
a strange GPR anomaly
This is a GPR profile I collected close to a storm drain catch basin. The catch basin is at the ground surface between 13 to 16 ft in this profile. The strong "slope" signals to its left look very unusual. 270 MHz antenna.
- Tue Sep 08, 2020 3:35 pm
- Forum: Near Surface Geophysics
- Topic: Guess what's in the GPR profile
- Replies: 11
- Views: 3445
Re: Guess what's in the GPR profile
Shielded or not, aboveground objects can show up in GPR data. GPR waves will be bounced back to the ground surface anyway -- they will keep travelling upward and then coming back down if there are aboveground objects.
- Tue Sep 08, 2020 3:28 pm
- Forum: Near Surface Geophysics
- Topic: Locating a man made tunnel
- Replies: 28
- Views: 11840
Re: Locating a man made tunnel
To be honest, the anomalies do look like voids. I just realize that your tunnel might not be in a regular shape. I mean the top and walls of the tunnel might not be smooth at all. The GPR signals will bounce around inside the tunnel and show the signatures like the anomalies shown in your GPR profil...
- Mon Sep 07, 2020 1:31 pm
- Forum: Near Surface Geophysics
- Topic: Locating a man made tunnel
- Replies: 28
- Views: 11840
Re: Locating a man made tunnel
At least you can see some anomalies. If the anomalies were caused by a tunnel, the tunnel might have collapsed. I think the more important question is, how large the area have you scanned. If you see this kind of anomalies everywhere, it's probably not a tunnel. If it's the only anomaly area you see...
- Sat Sep 05, 2020 4:56 pm
- Forum: General Geophysics and Geoscience
- Topic: wavefront vs wavefield
- Replies: 2
- Views: 609
Re: wavefront vs wavefield
If you drop a rock into a lake, the whole surface of the water becomes the wavefield as the water wave propagates. Each circle around the center where the wave starts is a wavefront. A wavefront is an interface (a straight line, a plane, a circle (as in this case)) or a ball, etc in the wavefield, o...