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Predicting Earthquakes question!!

I have a small question about remote sensing.

For Volcanoes remote sensing is used to look at changes in ground temperature, relief and ground movement etc.

Yet my notes say that for Earthquakes remote sensing is used to monitor the electromagnetic disturbance in the atmosphere directly above where an earthquake is about to occur?
Have I written this down wrong - shouldn't it be similar to the definition for Volcanoes?

Also, another method for monitoring earthquakes is monitoring the low-frequency electromagnetic activity.

I think I may have written my definitions wrong but I'm not sure?
Original post by MapleMaypole
I have a small question about remote sensing.

For Volcanoes remote sensing is used to look at changes in ground temperature, relief and ground movement etc.

Yet my notes say that for Earthquakes remote sensing is used to monitor the electromagnetic disturbance in the atmosphere directly above where an earthquake is about to occur?
Have I written this down wrong - shouldn't it be similar to the definition for Volcanoes?

Also, another method for monitoring earthquakes is monitoring the low-frequency electromagnetic activity.

I think I may have written my definitions wrong but I'm not sure?


Did I post this in the correct section?
Original post by MapleMaypole
I have a small question about remote sensing.

For Volcanoes remote sensing is used to look at changes in ground temperature, relief and ground movement etc.

Yet my notes say that for Earthquakes remote sensing is used to monitor the electromagnetic disturbance in the atmosphere directly above where an earthquake is about to occur?
Have I written this down wrong - shouldn't it be similar to the definition for Volcanoes?

Also, another method for monitoring earthquakes is monitoring the low-frequency electromagnetic activity.

I think I may have written my definitions wrong but I'm not sure?


Hi again Maple!

I personally haven't heard of using electromagnetic disturbances in the atmosphere to predict earthquakes, but that doesn't mean that what you've written is wrong. My A Level Geology textbook does however mention using remote sensing methods (tiltmeters, laser technology and GPS) to measure the slope of the ground level, as the area around the focus may tilt and swell slightly due to the formation of microcracks as stress within the rock becomes greater. Strain gauges in boreholes can also be used to measure deformation and therefore any increases in stress levels.

After having a brief look online, there are a few articles on using electromagnetic activity to predict earthquakes, so it looks like that may be correct.

I hope that helps :smile:
Original post by Leviathan1741
Hi again Maple!

I personally haven't heard of using electromagnetic disturbances in the atmosphere to predict earthquakes, but that doesn't mean that what you've written is wrong. My A Level Geology textbook does however mention using remote sensing methods (tiltmeters, laser technology and GPS) to measure the slope of the ground level, as the area around the focus may tilt and swell slightly due to the formation of microcracks as stress within the rock becomes greater. Strain gauges in boreholes can also be used to measure deformation and therefore any increases in stress levels.

After having a brief look online, there are a few articles on using electromagnetic activity to predict earthquakes, so it looks like that may be correct.

I hope that helps :smile:

Thanks!

I'll definitely add tiltmeters and GPS to my list of methods!
I have them both for predicting Volcanoes but didn't think about their use for earthquakes :smile: This is very informative thank you (If I get a good A-Level I'll definitely be thanking you) :tongue:

Are boreholes also used to measure groundwater levels for stress and tension? - we haven't learnt those yet
Original post by MapleMaypole
Thanks!

I'll definitely add tiltmeters and GPS to my list of methods!
I have them both for predicting Volcanoes but didn't think about their use for earthquakes :smile: This is very informative thank you (If I get a good A-Level I'll definitely be thanking you) :tongue:

Are boreholes also used to measure groundwater levels for stress and tension? - we haven't learnt those yet


Haha no problem :tongue:

My textbook refers to changes in water levels in wells rather than boreholes. As groundwater percolates down into the microcracks generated by the increasing stress before an earthquake, the water level in the well will fall :smile:

Annoyingly we've covered earthquakes already in my degree, but didn't go over the methods used to predict them, we focused more on the mechanisms which produce them and the ways in which they are recorded. Therefore I'm having to use my A Level textbook to try and help you :lol:
Original post by Leviathan1741
Haha no problem :tongue:

My textbook refers to changes in water levels in wells rather than boreholes. As groundwater percolates down into the microcracks generated by the increasing stress before an earthquake, the water level in the well will fall :smile:

Annoyingly we've covered earthquakes already in my degree, but didn't go over the methods used to predict them, we focused more on the mechanisms which produce them and the ways in which they are recorded. Therefore I'm having to use my A Level textbook to try and help you :lol:


It's good knowing that A-Level notes are still useful for Uni :smile:
Which course/uni do you go to?
I'm hoping to get the grades for Bristol BSc Geograhy! :smile:
Original post by MapleMaypole
It's good knowing that A-Level notes are still useful for Uni :smile:
Which course/uni do you go to?
I'm hoping to get the grades for Bristol BSc Geograhy! :smile:


I'm in my first year of BSc Geoscience at Keele! :smile:
Original post by MapleMaypole
I have a small question about remote sensing.

For Volcanoes remote sensing is used to look at changes in ground temperature, relief and ground movement etc.

Yet my notes say that for Earthquakes remote sensing is used to monitor the electromagnetic disturbance in the atmosphere directly above where an earthquake is about to occur?
Have I written this down wrong - shouldn't it be similar to the definition for Volcanoes?

Also, another method for monitoring earthquakes is monitoring the low-frequency electromagnetic activity.

I think I may have written my definitions wrong but I'm not sure?


Remote sensing is essentially observing a system remotely, i.e. no actual physical contact between the sensor and system. For example, Interferometric Synthetic Aperture Radar (InSAR) is used to measure the motion of the surface of the Earth. The idea is to difference the phase component of two radar images taken at two different times to obtain the ground motion that has occurred during the time interval. You might use this to possibly predict a volcanic eruption if you observe things like inflating/deflating of the volcanic edifice or changes of the flank perhaps, maybe observing some subsidence/uplift?

Light Detection and Ranging (LIDAR) is used in terrain mapping and to measure absorption (atmospheric purposes, things like volcanic emissions). It takes the form of satellite, airbourne or ground-based systems.

In terms of predicting an earthquake, it's, at our current level of understanding, impossible. We observe trends and at best, can forecast. Have a look at radon gas emissions, electromagnetic anomalies etc but I cannot stress enough (pun intended) that all these techniques have a very large degree of uncertainty.
(edited 7 years ago)
@Plagioclase might have some ideas
Original post by MapleMaypole
I have a small question about remote sensing.

For Volcanoes remote sensing is used to look at changes in ground temperature, relief and ground movement etc.

Yet my notes say that for Earthquakes remote sensing is used to monitor the electromagnetic disturbance in the atmosphere directly above where an earthquake is about to occur?
Have I written this down wrong - shouldn't it be similar to the definition for Volcanoes?

Also, another method for monitoring earthquakes is monitoring the low-frequency electromagnetic activity.

I think I may have written my definitions wrong but I'm not sure?


I have heard of people trying to use electromagnetic waves to predict earthquakes but this is a very contentious area of research and I think most seismologists would probably currently dismiss it as an academic curiosity at best, but more likely just pseudoscience. With the present state of science, there is no way of predicting earthquakes. We can make hazard maps estimating the earthquake risk to different areas based on things like past seismic history, strain build-up etc. but that's not really earthquake prediction.

Just accidentally deleted a bunch of stuff that I wrote about remote sensing of earthquakes and volcanoes. Basically, @hezzlington mentioned the important things, the one extra thing I'd say is that RADAR is more widely used than LiDAR because all the satellites use RADAR (LiDAR is used more for higher resolution terrestrial and airborne missions). For Volcanoes, I believe that there are seismic arrays around active volcanoes because rising magma is often accompanied by very characteristic seismic waves.
(edited 7 years ago)
Original post by hezzlington
Remote sensing is essentially observing a system remotely, i.e. no actual physical contact between the sensor and system. For example, Interferometric Synthetic Aperture Radar (InSAR) is used to measure the motion of the surface of the Earth. The idea is to difference the phase component of two radar images taken at two different times to obtain the ground motion that has occurred during the time interval. You might use this to possibly predict a volcanic eruption if you observe things like inflating/deflating of the volcanic edifice or changes of the flank perhaps, maybe observing some subsidence/uplift?

Light Detection and Ranging (LIDAR) is used in terrain mapping and to measure absorption (atmospheric purposes, things like volcanic emissions). It takes the form of satellite, airbourne or ground-based systems.

In terms of predicting an earthquake, it's, at our current level of understanding, impossible. We observe trends and at best, can forecast. Have a look at radon gas emissions, electromagnetic anomalies etc but I cannot stress enough (pun intended) that all these techniques have a very large degree of uncertainty.


Wow this is very in depth! :smile:
I might have to read more about LiDAR as that sounds very interesting.
Data can be gathered about what occurs when earthquakes are about to happen, but it varies between earthquakes and they're still very unpredictable.
Original post by Plagioclase
I have heard of people trying to use electromagnetic waves to predict earthquakes but this is a very contentious area of research and I think most seismologists would probably currently dismiss it as an academic curiosity at best, but more likely just pseudoscience. With the present state of science, there is no way of predicting earthquakes. We can make hazard maps estimating the earthquake risk to different areas based on things like past seismic history, strain build-up etc. but that's not really earthquake prediction.

Just accidentally deleted a bunch of stuff that I wrote about remote sensing of earthquakes and volcanoes. Basically, @hezzlington mentioned the important things, the one extra thing I'd say is that RADAR is more widely used than LiDAR because all the satellites use RADAR (LiDAR is used more for higher resolution terrestrial and airborne missions). For Volcanoes, I believe that there are seismic arrays around active volcanoes because rising magma is often accompanied by very characteristic seismic waves.


If this comes up in the exam I think I'll mention low-frequency electromagnetic disturbances, then link it to how earthquakes are hard to predict etc and there are a variety or methods which may/may not be useful.

I'll also have to look into seismic arrays more, that sounds very useful to put into an exam! :smile:

Thank you for the help, I'm a lot less confused now
Original post by Leviathan1741
I'm in my first year of BSc Geoscience at Keele! :smile:


Ooohhh, Keele is very nice! I almost put them as a choice :smile:
Original post by MapleMaypole
If this comes up in the exam I think I'll mention low-frequency electromagnetic disturbances, then link it to how earthquakes are hard to predict etc and there are a variety or methods which may/may not be useful.

I'll also have to look into seismic arrays more, that sounds very useful to put into an exam! :smile:

Thank you for the help, I'm a lot less confused now


If you do mention it (which I honestly wouldn't recommend) then please make sure you mention the actually scientifically valid methods of remote sensing first!
Original post by Plagioclase
If you do mention it (which I honestly wouldn't recommend) then please make sure you mention the actually scientifically valid methods of remote sensing first!


I will :smile: It'll most likely come up as a 40 marker so I'll mention remote sensing, seismic activity, groundwater levels etc

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