What is Ground Penetrating Radar(GPR)?
Technology has helped in developing equipment and machines to make discoveries easier and more precise. One such technological device in this regard is the Ground Penetrating Radar. Much like the traditional radar systems that we are more familiar with.
Ground Penetrating Radar (also called echo sounding, Georadar, surface penetrating radar, or ground probing radar) is an electromagnetic method used to explore subsurface properties of not too far distances (usually 10s of meters away and within 10-1000 MHz band).
Ground Penetrating Radar exploits the use of radiated electromagnetic waves that have gone into the ground to define the physical boundaries of both natural and man-made surfaces. This technological device is very suitable for ground subsurfaces as they produce a better image representation of the findings within the subsurface than any other method available.
The data from Ground Penetrating Radar (GPR) can be acquired in a number of ways to achieve different results. They include:
- Using a small area for ground-based instrumentation which provides information for a very small ground area.
- Using aircraft-based instrumentation to gather information for a larger area (usually not too far distances)
- Using satellite-based instrumentation to gather regional information about activities within the subsurface of the regional environment.
From this, we can see that GPR can be used at various levels and sizes to gain access to information about the environment concerned.
For Ground Penetrating Radar to yield the desired result, the problem must be defined and the intent of the survey clearly identified. If the intentions of the survey are not clearly defined and the depth to be covered is farther than what GPR can cover, then the whole GPR process is rendered useless.
Therefore, researchers and users of this technology must define their problems and goals in order to know for a fact if GPR is the right solution.
The history of the ground-penetrating radar goes back to 1910. The first recorded patent for a system that utilized a continuous-wave radar to locate objects that have been buried was submitted by Gotthelf Leimbach and Heinrich Löwy. A patent was filed by Hülsenbeck for a radar system that pulses rather than uses a continuous wave. W. Stern used this new system with better depth resolution by measuring the depth of an iceberg in 1929.
Since then many researchers and surveyors have utilized this technology in a number of ways. GPR has been used as a solution in various aspects. It has been used in mining, construction, hydrogeology, archaeology, and many more research areas. This piece will help you understand the uses of GPR in our everyday research and the improvement of our lives.
Uses of Ground Penetrating Radar
Some of the areas that GPR has been utilized over the years include the following:
Archaeology
Ground Penetrating Radar is greatly used in archaeology research since it is a non-destructive method of resolving small objects. Mostly, GPR is used on very old and historical buildings by utilizing a very high frequency which will help in detecting cracks. With the discovery of cracks in these walls, such buildings can be worked on and preserved to stay longer.
Also, GPR has been used in the discovery of artifacts beneath the ground surface. Artifacts that could not be found easily by digging are made visible through the electromagnetic functions of the ground-penetrating radar technology. Underground buildings and ancient buried cities are made visible by the GPR technology.
With the use of GPR, archaeologists have been able to make groundbreaking discoveries over the years. Archaeologists can now penetrate through the ground and view the mysteries that lay beneath us without actually breaking or digging surfaces at all.
Though ground penetrating radar is not used to find buried fossils. Archeologist have attempted to use GPR, the main problem is that fossil bones are usually at the same density as the rocks around them, making it hard to spot a significant difference between them that would indicate where to dig. Furthermore, fossils are frequently tiny, therefore a level of precision isn’t always feasible; and there are plenty of subtle distinctions and quirks in local geology that might cause false negatives.
Ground Penetrating Radar can be used to find tunnels and is potentially going to be used by the U.S. border patrol to help find underground tunnels dug by drug and human smugglers.
The Department of Homeland Security (DHS) is collaborating with Lockheed Martin to create a ground-penetrating radar technology that would be developed particularly for finding subterranean tunnels. If the technique works, it will allow agents to find and seal tunnels at nearly the same speed as they’re created.
Because their tunnels are often much deeper then the typical GPR use their radar will employ the use of much lower frequencies that will allow for deeper penetration.
Construction and Civil Engineering
GPR can be utilized in the areas of construction and engineering by identifying the best areas to build on or not to construct on. Since it is nondestructive, engineers can get information about the subsurface quicker and faster before any form of construction commences.
GPR helps engineers confirm whether or not there are underground power cables along the line of construction, rebars, or conduits before breaking through the ceramic. This simply means that engineers can now easily locate the very best location for construction purposes.
Also, the relocation of underground properties can be quite difficult as they may cause strain, stress, and even heavy traffic if not properly planned. Therefore, GPR helps to identify the particular underground infrastructure to be relocated and helps engineers plan on how best to carry out the relocation exercise.
Security and Military
Ground Penetrating Radar seems to cover all areas of life, including the security aspects. GPR can be used during forensic investigations by non-destructively detecting buried and hidden targets, as well as locating their precise geometries.
Forensics and law enforcement agent utilize GPR in the discovery of graves, hidden or buried evidence as well as stolen goods.
Also, Ground Penetrating Radar is used in the military to help detect unexploded items within the ground surface which enables the men of the force to avert such disasters. Also, GPR is utilized alongside other geophysical methods (as well as GPS) in order to map out underground tunnels for military operations. Therefore, it is safe to say that GPR is utilized even in the security aspects of our lives.
Exploration and Mining
Ground Penetrating Radar has been of great interest in the mining and exploration industry for a long time now especially because of its help in underground mapping and borehole investigations. With the use of GPR technology in the mining sector, the players within the sectors can set mining protocols as a result of the interpretation of the GPR results.
Since GPR provides very accurate information from gauging the mining environment before exploration, the mining agency can therefore employ the relevant risk management unique to the results of the GPR analysis.
Though is it far from a guarantee that you can find gold or silver with ground penetrating radar. Gold is a vein deposit, appearing in small quantities with the host rock. Gold content was 10g/t of ore (median) at KGF mines in India during its hay days. Because of its sparse and vein-like makeup, gold ore’s presence is frequently missed using GPR by conventional reflection approach. GPR cannot be utilized to look for any other metals deposits unless they form sheet deposits.
GPR tomography does show promise in detecting sparse metal deposits. The same may be said regarding gold detection via boreholes.
Hydrogeology
Hydrogeology is that area of geology that deals with the movement and distribution of groundwater within the earth’s crust. In this regard, GPR is used by environmental scientists to discover the measure of movement and size of groundwater.
With this measurement, they have the knowledge as to what quantity of groundwater is available for public use and begin to plan ways by which such groundwater can be utilized.
The ground penetrating radar (GPR) system is used to detect and identify underground bodies of water. GPR can help find and identify aquifer water or nonmetallic mines, which is a very exciting prospect for the future.
Conclusion
Ground Penetrating Radar technology has come to stay and for a long time now, it has proven to be useful in many areas. The listed areas above are just a few of the ways GPR technology can be utilized. Others include radio glaciology, geologic interpretation, etc. Ground penetrating radars uses will continue to expend into the future.