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material composition. While it can identify items such as pipes, voids, and soil, it cannot identify the specific materials, such as gold and precious gems. It can, however, be useful in providing subsurface mapping of potential gem-bearing pockets, or "vugs". The readings can be confused by moisture in the ground and they can't separate gem-bearing pockets from non-gem-bearing ones.
112:, and the radiated power all may limit the effective depth range of GPR investigation. Increases in electrical conductivity attenuate the introduced electromagnetic wave, and thus the penetration depth decreases. Because of frequency-dependent attenuation mechanisms, higher frequencies do not penetrate as far as lower frequencies. However, higher frequencies may provide improved
20:
361:, Lawrence Conyers, one of the first archaeological specialists in GPR, described the process. Conyers published research using GPR in El Salvador in 1996, in the Four Corners region Chaco period in southern Arizona in 1997, and in a medieval site in Ireland in 2018. Informed by Conyer's research, the Institute of Prairie and Indigenous Archaeology at the
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demonstrated in 2012 for autonomous vehicle steering and fielded for military operation in 2013. Highway speed centimeter-level localization during a night-time snow-storm was demonstrated in 2016. This technology was exclusively licensed and commercialized for vehicle safety in ADAS and
Autonomous Vehicle positioning and lane-keeping systems by
85:, and detects the reflected signals from subsurface structures. GPR can have applications in a variety of media, including rock, soil, ice, fresh water, pavements and structures. In the right conditions, practitioners can use GPR to detect subsurface objects, changes in material properties, and voids and cracks.
116:. Thus operating frequency is always a trade-off between resolution and penetration. Optimal depth of subsurface penetration is achieved in ice where the depth of penetration can achieve several thousand metres (to bedrock in Greenland) at low GPR frequencies. Dry sandy soils or massive dry materials such as
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for over half a century. Its most widespread uses have been the measurement of ice thickness, subglacial topography, and ice sheet stratigraphy. It has also been used to observe the subglacial and conditions of ice sheets and glaciers, including hydrology, thermal state, accumulation, flow history,
283:
A recent novel approach to vehicle localization using prior map based images from ground penetrating radar has been demonstrated. Termed "Localizing Ground
Penetrating Radar" (LGPR), centimeter level accuracies at speeds up to 100 km/h (60 mph) have been demonstrated. Closed-loop operation was first
155:
The first patent for a system designed to use continuous-wave radar to locate buried objects was submitted by
Gotthelf Leimbach and Heinrich Löwy in 1910, six years after the first patent for radar itself (patent DE 237 944). A patent for a system using radar pulses rather than a continuous wave was
635:
A special kind of GPR uses unmodulated continuous-wave signals. This holographic subsurface radar differs from other GPR types in that it records plan-view subsurface holograms. Depth penetration of this kind of radar is rather small (20–30 cm), but lateral resolution is enough to discriminate
2690:
Jaufer, Rakeeb M., Amine
Ihamouten, Yann Goyat, Shreedhar S. Todkar, David Guilbert, Ali Assaf, and Xavier Dérobert. 2022. "A Preliminary Numerical Study to Compare the Physical Method and Machine Learning Methods Applied to GPR Data for Underground Utility Network Characterization" Remote Sensing
328:
The concept of radar is familiar to most people. With ground penetrating radar, the radar signal – an electromagnetic pulse – is directed into the ground. Subsurface objects and stratigraphy (layering) will cause reflections that are picked up by a receiver. The travel time of the reflected signal
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GPR depth slices showing a crypt in a historic cemetery. These planview maps show subsurface structures at different depths. Sixty lines of data – individually representing vertical profiles – were collected and assembled as a 3-dimensional data array that can be horizontally "sliced" at different
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One of the other main applications for ground-penetrating radars is for locating underground utilities. Standard electromagnetic induction utility locating tools require utilities to be conductive. These tools are ineffective for locating plastic conduits or concrete storm and sanitary sewers.
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When determining depth capabilities, the frequency range of the antenna dictates the size of the antenna and the depth capability. The grid spacing which is scanned is based on the size of the targets that need to be identified and the results required. Typical grid spacings can be 1 meter,
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The principal disadvantage of GPR is that it is severely limited by less-than-ideal environmental conditions. Fine-grained sediments (clays and silts) are often problematic because their high electrical conductivity causes loss of signal strength; rocky or heterogeneous sediments scatter the GPR
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The speed at which a radar signal travels is dependent upon the composition of the material being penetrated. The depth to a target is determined based on the amount of time it takes for the radar signal to reflect back to the unit’s antenna. Radar signals travel at different velocities through
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is sensitive to changes in material composition; detecting changes requires movement. When looking through stationary items using surface-penetrating or ground-penetrating radar, the equipment needs to be moved in order for the radar to examine the specified area by looking for differences in
88:
GPR uses high-frequency (usually polarized) radio waves, usually in the range 10 MHz to 2.6 GHz. A GPR transmitter and antenna emits electromagnetic energy into the ground. When the energy encounters a buried object or a boundary between materials having different
259:
Military applications of ground-penetrating radar include detection of unexploded ordnance and detecting tunnels. In military applications and other common GPR applications, practitioners often use GPR in conjunction with other available geophysical techniques such as
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introduced legislation to regulate GPR equipment and GPR operators to control excess emissions of electromagnetic radiation. The
European GPR association (EuroGPR) was formed as a trade association to represent and protect the legitimate use of GPR in Europe.
560:
images. Data may be presented as three-dimensional blocks, or as horizontal or vertical slices. Horizontal slices (known as "depth slices" or "time slices") are essentially planview maps isolating specific depths. Time-slicing has become standard practice in
661:
SewerVUE Technology, an advanced pipe condition assessment company utilizes Pipe
Penetrating Radar (PPR) as an in pipe GPR application to see remaining wall thickness, rebar cover, delamination, and detect the presence of voids developing outside the pipe.
373:. By June 2021, the Institute had used GPR to locate suspected unmarked graves in areas near historic cemeteries and Indian Residential Schools. On May 27, 2021, it was reported that the remains of 215 children were found using GPR at a burial site at the
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tend to be resistive rather than conductive, and the depth of penetration could be up to 15 metres (49 ft). However, in moist or clay-laden soils and materials with high electrical conductivity, penetration may be as little as a few centimetres.
642:
In Pipe-Penetrating Radar (IPPR) and In Sewer GPR (ISGPR) are applications of GPR technologies applied in non-metallic-pipes where the signals are directed through pipe and conduit walls to detect pipe wall thickness and voids behind the pipe walls.
392:
Advancements in GPR technology integrated with various 3D software modelling platforms generate three-dimensional reconstructions of subsurface "shapes and their spatial relationships". By 2021, this has been "emerging as the new standard".
233:
Borehole radars utilizing GPR are used to map the structures from a borehole in underground mining applications. Modern directional borehole radar systems are able to produce three-dimensional images from measurements in a single borehole.
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The most significant performance limitation of GPR is in high-conductivity materials such as clay soils and soils that are salt contaminated. Performance is also limited by signal scattering in heterogeneous conditions (e.g. rocky soils).
340:
without any risk of damaging them. Among methods used in archaeological geophysics, it is unique both in its ability to detect some small objects at relatively great depths, and in its ability to distinguish the depth of anomaly sources.
1097:
Lowe, Kelsey M; Wallis, Lynley A.; Pardoe, Colin; Marwick, Benjamin; Clarkson, Christopher J; Manne, Tiina; Smith, M.A.; Fullagar, Richard (2014). "Ground-penetrating radar and burial practices in western Arnhem Land, Australia".
207:. It is of some utility in prospecting for gold nuggets and for diamonds in alluvial gravel beds, by finding natural traps in buried stream beds that have the potential for accumulating heavier particles. The Chinese lunar rover
547:
ice fabric, and bed geology. In planetary science, ice penetrating radar has also been used to explore the subsurface of the Polar Ice Caps on Mars and comets. Missions are planned to explore the icy moons of
Jupiter.
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Seu, Roberto; Phillips, Roger J.; Biccari, Daniela; Orosei, Roberto; Masdea, Arturo; Picardi, Giovanni; Safaeinili, Ali; Campbell, Bruce A.; Plaut, Jeffrey J.; Marinangeli, Lucia; Smrekar, Suzanne E. (18 May 2007).
159:
Further developments in the field remained sparse until the 1970s, when military applications began driving research. Commercial applications followed and the first affordable consumer equipment was sold in 1975.
658:. Police showed how to watch people up to two rooms away laterally and through floors vertically, could see metal lumps that might be weapons; GPR can even act as a motion sensor for military guards and police.
1566:
Schroeder, Dustin M.; Bingham, Robert G.; Blankenship, Donald D.; Christianson, Knut; Eisen, Olaf; Flowers, Gwenn E.; Karlsson, Nanna B.; Koutnik, Michelle R.; Paden, John D.; Siegert, Martin J. (April 2020).
167:(Apollo Lunar Sounder Experiment) in orbit around the Moon. It was able to record depth information up to 1.3 km and recorded the results on film due to the lack of suitable computer storage at the time.
538:. This allows echoes from the base of the ice sheet to be detected through ice thicknesses greater than 4 km. The subsurface observation of ice masses using radio waves has been an integral and evolving
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In the field of cultural heritage GPR with high frequency antenna is also used for investigating historical masonry structures, detecting cracks and decay patterns of columns and detachment of frescoes.
665:
EU Detect Force
Technology, an advanced soil research company, design utilizes X6 Plus Grounding Radar (XGR) as an hybrid GPR application for military mine detection and also police bomb detection.
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Individual lines of GPR data represent a sectional (profile) view of the subsurface. Multiple lines of data systematically collected over an area may be used to construct three-dimensional or
324:
GPR depth section (profile) showing a single line of data from the survey of the historic crypt shown above. The domed roof of the crypt can be seen between 1 and 2.5 meters below surface.
35:
arrivals (arrows) indicate the presence of diffractors buried beneath the surface, possibly associated with human burials. Reflections from soil layering are also present (dashed lines).
93:, it may be reflected or refracted or scattered back to the surface. A receiving antenna can then record the variations in the return signal. The principles involved are similar to
1736:
Bamber, J. L.; Griggs, J. A.; Hurkmans, R. T. W. L.; Dowdeswell, J. A.; Gogineni, S. P.; Howat, I.; Mouginot, J.; Paden, J.; Palmer, S.; Rignot, E.; Steinhage, D. (22 March 2013).
101:
energy, and energy may be reflected at boundaries where subsurface electrical properties change rather than subsurface mechanical properties as is the case with seismic energy.
58:
the subsurface. It is a non-intrusive method of surveying the sub-surface to investigate underground utilities such as concrete, asphalt, metals, pipes, cables or masonry. This
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and cemeteries. GPR is used in law enforcement for locating clandestine graves and buried evidence. Military uses include detection of mines, unexploded ordnance, and tunnels.
332:
GPR can be a powerful tool in favorable conditions (uniform sandy soils are ideal). Like other geophysical methods used in archaeology (and unlike excavation) it can locate
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filed in 1926 by Dr. Hülsenbeck (DE 489 434), leading to improved depth resolution. A glacier's depth was measured using ground penetrating radar in 1929 by W. Stern.
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Kofman, W.; Herique, A.; Barbin, Y.; Barriot, J.-P.; Ciarletti, V.; Clifford, S.; Edenhofer, P.; Elachi, C.; Eyraud, C.; Goutail, J.-P.; Heggy, E. (31 July 2015).
624:
Ground-penetrating radar uses a variety of technologies to generate the radar signal: these are impulse, stepped frequency, frequency-modulated continuous-wave (
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different types of materials. It is possible to use the depth to a known object to determine a specific velocity and then calibrate the depth calculations.
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which used the technology to determine a suitable area for examination by means of excavations. GPR was also used to recover £150,000 in cash ransom that
1618:"Automated monitoring of subglacial hydrological processes with ground-penetrating radar (GPR) at high temporal resolution: scope and potential pitfalls"
1455:
2417:. Code of Practice in respect of the control, use and application of Ground Probing Radar (GPR) and Wall Probing Radar (WPR) systems and equipment.
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different types of landmines in the soil, or cavities, defects, bugging devices, or other hidden objects in walls, floors, and structural elements.
900:
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1508:"A novel approach to 3D modelling ground-penetrating radar (GPR) data – a case study of a cemetery and applications for criminal investigation"
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are generally in contact with the ground for the strongest signal strength; however, GPR air-launched antennas can be used above the ground.
366:
238:
Since GPR detects variations in dielectric properties in the subsurface, it can be highly effective for locating non-conductive utilities.
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In May 2020, the U.S. military ordered ground-penetrating radar system from
Chemring Sensors and Electronics Systems (CSES), to detect
1278:
1068:"MIT Lincoln Laboratory: News: Lincoln Laboratory demonstrates highly accurate vehicle localization under adverse weather conditions"
370:
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indicates the depth. Data may be plotted as profiles, as planview maps isolating specific depths, or as three-dimensional models.
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Conyers, Lawrence (1 October 1996). "Archaeological evidence for dating the Loma
Caldera eruption, Ceren, El Salvador".
925:
Hofinghoff, Jan-Florian (2013). "Resistive Loaded Antenna for Ground Penetrating Radar Inside a Bottom Hole Assembly".
386:
374:
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218:(NDT) of structures and pavements, locating buried structures and utility lines, and studying soils and bedrock. In
875:
297:
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GPR is used on vehicles for close-in high-speed road survey and landmine detection as well as in stand-off mode.
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3 ft, 5 ft, 10 ft, 20 ft for ground surveys, and for walls and floors 1 inch–1 ft.
378:
2439:
1795:
Fretwell, P.; Pritchard, H. D.; Vaughan, D. G.; Bamber, J. L.; Barrand, N. E.; et al. (28 February 2013).
508:. This technique is also commonly referred to as "Ice Penetrating Radar (IPR)" or "Radio Echo Sounding (RES)".
840:
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272:
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GPR is used by criminologists, historians, and archaeologists to search burial sites. In his publication,
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978:"Army orders ground-penetrating radar system from CSES for detecting hidden IEDs in $ 200.2 million deal"
655:
2519:
Ivashov, S. I.; Razevig, V. V.; Vasiliev, I. A.; Zhuravlev, A. V.; Bechtel, T. D.; Capineri, L. (2011).
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Wall-penetrating radar can read through non-metallic structures as demonstrated for the first time by
629:
562:
265:
223:
219:
63:
868:"A review of the alluvial diamond industry and the gravels of the North West Province, South Africa"
1481:"Saskatchewan First Nation discovers hundreds of unmarked graves at former residential school site"
676:
1506:
Kelly, T. B.; Angel, M. N.; O’Connor, D. E.; Huff, C. C.; Morris, L.; Wach, G. D. (22 June 2021).
1383:
1000:"Localizing ground penetrating RADAR: A step toward robust autonomous ground vehicle localization"
433:
2815:
2803:
1865:
1168:"Application of Neural Network Enhanced Ground-Penetrating Radar to Localization of Burial Sites"
511:
105:
1693:
Remote Sensing of Glaciers: Techniques for Topographic, Spatial and Thematic Mapping of Glaciers
2584:
2464:
Zhuravlev, A.V.; Ivashov, S.I.; Razevig, V.V.; Vasiliev, I.A.; Türk, A.S.; Kizilay, A. (2013).
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382:
333:
301:
261:
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59:
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A general overview of geophysical methods in archaeology can be found in the following works:
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Considerable expertise is necessary to effectively design, conduct, and interpret GPR surveys.
565:, because horizontal patterning is often the most important indicator of cultural activities.
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1796:
362:
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305:
227:
222:, GPR is used to define landfills, contaminant plumes, and other remediation sites, while in
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74:
2046:"Accidents and opportunities: a history of the radio echo-sounding of Antarctica, 1958–79"
1866:"Investigations of the form and flow of ice sheets and glaciers using radio-echo sounding"
1041:
Enabling autonomous vehicles to drive in the snow with localizing ground penetrating radar
8:
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55:
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1390:. SpringerBriefs in Geography. Cham: Springer International Publishing. pp. 75–90.
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Mazurkiewicz, Ewelina; Tadeusiewicz, Ryszard; Tomecka-Suchoń, Sylwia (20 October 2016).
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1955:
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950:
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113:
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Principles, methods and results of electrodynamic thickness measurement of glacier ice
1889:
998:
Cornick, Matthew; Koechling, Jeffrey; Stanley, Byron; Zhang, Beijia (1 January 2016).
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First Nation land in British Columbia. In June 2021, GPR technology was used by the
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Srivastav, A.; Nguyen, P.; McConnell, M.; Loparo, K. N.; Mandal, S. (October 2020).
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Turchetti, Simone; Dean, Katrina; Naylor, Simon; Siegert, Martin (September 2008).
1986:
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site, which had been in operation for a century until it was closed down in 1996.
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781:(2nd ed.). Knoval (Institution of Engineering and Technology). pp. 1–4.
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Relatively high energy consumption can be problematic for extensive field surveys.
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505:
457:
403:
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140:
133:
2719:
Introduction to ground penetrating radar: inverse scattering and data processing
2547:
2528:
IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing
2341:
Bruzzone, L; Alberti, G; Catallo, C; Ferro, A; Kofman, W; Orosei, R (May 2011).
2217:"Properties of the 67P/Churyumov-Gerasimenko interior revealed by CONSERT radar"
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82:
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1991:
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28:
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Proceedings of the 15th International Conference on Ground Penetrating Radar
2466:"Holographic subsurface imaging radar for applications in civil engineering"
2274:
2241:
2216:
2184:
2159:
1368:
1127:"Some examples of GPR prospecting for monitoring of the monumental heritage"
830:"The Apollo Lunar Sounder Radar System" - Proceedings of the IEEE, June 1974
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Glaciers are particularly well suited to investigation by radar because the
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1541:
731:
515:
248:
208:
90:
70:
2800:"Short movie showing acquisition, processing and accuracy of GPR readings"
2656:"International No-Dig Meets in Singapore - Trenchless Technology Magazine"
2521:"Holographic Subsurface Radar of RASCAN Type: Development and Application"
2520:
2465:
1824:
1797:"Bedmap2: improved ice bed, surface and thickness datasets for Antarctica"
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has a GPR on its underside to investigate the soil and crust of the Moon.
2480:
2299:
1642:
1617:
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Kulessa, B.; Booth, A. D.; Hobbs, A.; Hubbard, A. L. (18 December 2008).
1294:"Ground-Penetrating Radar Techniques to Discover and Map Historic Graves"
535:
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had buried in a field, following his 1992 kidnapping of an estate agent.
200:
163:
In 1972, the Apollo 17 mission carried a ground penetrating radar called
144:
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An overview of scientific and engineering applications can be found in:
2682:"Receiver Design for a Directional Borehole Radar System (dissertation)"
2126:
1593:
1568:
1279:
10.1002/(SICI)1520-6548(199610)11:5<377::AID-GEA1>3.0.CO;2-5
2475:. IET International Radar Conference. Xi'an, China: IET. p. 0065.
1959:
1935:
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Ground-penetrating Radar and Magnetometry for Buried Landscape Analysis
1309:
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The "Mineseeker Project" seeks to design a system to determine whether
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Interpretation of radar-grams is generally non-intuitive to the novice.
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543:
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481:
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signal, weakening the useful signal while increasing extraneous noise.
311:
94:
47:
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2135:
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1431:"Geophysics and Unmarked Graves: a Short Introduction for Communities"
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179:
Ground penetrating radar in use near Stillwater, Oklahoma, USA in 2010
2692:
2070:
1975:"Radio-Echo Sounding: Glaciological Interpretations and Applications"
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485:
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method similar to ground-penetrating radar and typically operates at
465:
243:
121:
109:
98:
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32:
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1951:
1923:. University of Cambridge, Scott Polar Research Institute Cambridge.
1456:"Remains of 215 children found at former residential school in B.C."
1701:
632:(DSP) to process the data during survey work rather than off-line.
473:
187:
Ground penetrating radar survey of an archaeological site in Jordan
125:
23:
A ground-penetrating radargram collected on a historic cemetery in
320:
97:, except GPR methods implement electromagnetic energy rather than
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196:
117:
24:
16:
Geophysical method that uses radar pulses to image the subsurface
577:
Other disadvantages of currently available GPR systems include:
415:
2843:
2518:
2463:
732:"A Highly Digital Multiantenna Ground-Penetrating Radar System"
143:
to be a valuable means of assessing the presence and amount of
2415:
Electromagnetic compatibility and Radio spectrum Matters (ERM)
1794:
1735:
729:
300:. GPR can be used to detect and map subsurface archaeological
241:
GPR was often used on the Channel 4 television programme
183:
680:
591:
477:
51:
2742:
Ground-penetrating radar: an introduction for archaeologists
1351:
Ground-penetrating radar: an introduction for archaeologists
997:
2792:"GprMax – GPR numerical simulator based on the FDTD method"
2733:
Seeing Beneath the Soil. Prospecting Methods in Archaeology
2340:
1690:
Pellikka, Petri; Rees, W. Gareth, eds. (16 December 2009).
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from the original on 22 December 2021 – via YouTube.
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from the original on 22 December 2021 – via YouTube.
2275:"SHARAD sounding radar on the Mars Reconnaissance Orbiter"
2214:
2043:
2783:
1936:"Airborne Radio Echo Sounding of the Greenland Ice Sheet"
385:
in Saskatchewan to locate 751 unmarked gravesites on the
78:
19:
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2769:
Revealing the Buried Past: Geophysics for Archaeologists
2271:
1615:
1213:
191:
GPR has many applications in a number of fields. In the
2585:"Ground Penetrating Radar(GPR) Systems – Murphysurveys"
2433:"An impulse generator for the ground penetrating radar"
2343:"Subsurface Radar Sounding of the Jovian Moon Ganymede"
1921:
Antarctica: Glaciological and Geophysical Folio, Vol. 2
1788:
1096:
1505:
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Ground penetrating radar survey is one method used in
2107:
Journal of Environmental & Engineering Geophysics
1859:
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1731:
1729:
1561:
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1424:
1422:
1226:
Interpreting Ground-penetrating Radar for Archaeology
1159:
866:
Wilson, M. G. C.; Henry, G.; Marshall, T. R. (2006).
628:), and noise. Systems on the market in 2009 also use
359:
Interpreting Ground-penetrating Radar for Archaeology
139:
Cross borehole GPR has developed within the field of
1675:
Bogorodsky, VV; Bentley, CR; Gudmandsen, PE (1985).
736:
IEEE Transactions on Instrumentation and Measurement
275:(IEDs) buried in roadways, in $ 200.2 million deal.
865:
2824:"GPR Electromagnetic Emissions Safety Information"
2315:
1854:
1726:
1556:
1419:
285:
2766:
2613:
1848:"A Brief History Of Radio – Echo Sounding Of Ice"
2854:
2710:Ground Penetrating Radar Theory and Applications
806:"History of Ground Penetrating Radar Technology"
2419:European Telecommunications Standards Institute
2101:Bingham, R. G.; Siegert, M. J. (1 March 2007).
1863:
1344:
1342:
1285:
1044:(video). MIT Lincoln Laboratory. 24 June 2016.
613:European Telecommunications Standards Institute
2739:
2679:
2322:Blankenship, DD (2018). "Reasons for Europa".
2100:
2050:The British Journal for the History of Science
1348:
288:and marketed as Ground Positioning Radar(tm).
2016:Radar Methods for the Exploration of Glaciers
927:IEEE Transactions on Antennas and Propagation
2784:"EUROGPR – The European GPR regulatory body"
2735:. London, United Kingdom: B.T. Batsford Ltd.
1864:Dowdeswell, J A; Evans, S (1 October 2004).
1689:
1473:
1375:
1339:
1250:
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367:National Centre for Truth and Reconciliation
2740:Conyers, Lawrence B; Goodman, Dean (1997).
2321:
2160:"Radar Soundings of the Subsurface of Mars"
2103:"Radio-Echo Sounding Over Polar Ice Masses"
1738:"A new bed elevation dataset for Greenland"
1349:Conyers, Lawrence B; Goodman, Dean (1997).
833:
440:to it so that it can be better illustrated.
2812:"FDTD Animation of sample GPR propagation"
2614:Ékes, C.; Neducza, B.; Takacs, P. (2014).
2389:"Gems and Technology – Vision Underground"
2018:(PhD). California Institute of Technology.
1933:
1499:
1229:. Routledge & CRC Press. p. 220.
924:
776:
2421:. September 2009. ETSI EG 202 730 V1.1.1.
2298:
2240:
2183:
2134:
2069:
1990:
1823:
1771:
1761:
1651:
1641:
1592:
1523:
1429:Wadsworth, William T. D. (22 July 2020).
1428:
1292:Conyers, Lawrence B. (1 September 2006).
1150:
1015:
369:, have been using GPR in their survey of
2381:
2033:. Zeitschrift für Gletscherkunde 18, 24.
2013:
1846:Allen, Christopher (26 September 2008).
1125:Masini, N; Persico, R; Rizzo, E (2010).
800:
798:
319:
310:
182:
174:
18:
2716:
2473:IET International Radar Conference 2013
2157:
1381:
1291:
1256:
1222:
619:
278:
2855:
2595:from the original on 10 September 2017
2565:from the original on 29 September 2013
2500:from the original on 29 September 2013
1918:
1223:Conyers, Lawrence B. (1 April 2014) .
108:of the ground, the transmitted center
2730:
2395:from the original on 22 February 2014
2028:
1972:
1845:
1131:Journal of Geophysics and Engineering
993:
991:
795:
2744:. Walnut Creek, CA: AltaMira Press.
1353:. Walnut Creek, CA: AltaMira Press.
1048:from the original on 19 January 2017
982:Military & Aerospace Electronics
812:from the original on 2 February 2017
701:"How Ground Penetrating Radar Works"
409:
371:Indian Residential Schools in Canada
2767:Gaffney, Chris; John Gater (2003).
2707:
845:Lunar and Planetary Institute (LPI)
606:
13:
2698:
2693:https://doi.org/10.3390/rs14041047
2445:from the original on 18 April 2015
988:
425:needs additional or more specific
387:Marieval Indian Residential School
375:Kamloops Indian Residential School
14:
2879:
2776:
2771:. Stroud, United Kingdom: Tempus.
1569:"Five decades of radioglaciology"
214:Engineering applications include
2158:Picardi, G. (23 December 2005).
1934:Gudmandsen, P. (December 1969).
1459:The Canadian Press via APTN News
906:from the original on 5 July 2013
876:South African Journal of Geology
414:
402:This section is an excerpt from
2648:
2607:
2577:
2512:
2457:
2425:
2407:
2334:
2324:42nd COSPAR Scientific Assembly
2279:Journal of Geophysical Research
2265:
2151:
2094:
2037:
2022:
2007:
1966:
1927:
1912:
1839:
1683:
1668:
1609:
1525:10.1016/j.forsciint.2021.110882
1448:
1172:Applied Artificial Intelligence
1118:
1090:
1060:
1032:
970:
352:
170:
2660:Trenchless Technology Magazine
1870:Reports on Progress in Physics
1512:Forensic Science International
961:
918:
859:
824:
770:
723:
693:
654:in 1984 while surveying an ex
568:
291:
1:
2844:"Utility mapping with 3D GPR"
2826:. 17 May 2016. Archived from
1382:Conyers, Lawrence B. (2018).
1184:10.1080/08839514.2016.1274250
686:
396:
1622:Geophysical Research Letters
365:, in collaboration with the
273:improvised explosive devices
7:
2548:10.1109/JSTARS.2011.2161755
1890:10.1088/0034-4885/67/10/R03
1396:10.1007/978-3-319-70890-4_7
672:are present in areas using
656:Russian Embassy in Canberra
563:archaeological applications
254:
10:
2884:
2731:Clark, Anthony J. (1996).
2717:Persico, Raffaele (2014).
2684:. University of Wuppertal.
2624:10.1109/ICGPR.2014.6970448
2359:10.1109/JPROC.2011.2108990
1384:"Medieval Site in Ireland"
841:"Lunar Sounder Experiment"
401:
150:
2062:10.1017/S0007087408000903
1992:10.3189/S0022143000034262
1696:(0 ed.). CRC Press.
1152:10.1088/1742-2132/7/2/S05
1004:Journal of Field Robotics
630:Digital signal processing
552:Three-dimensional imaging
298:archaeological geophysics
266:electromagnetic induction
220:environmental remediation
132:Ground-penetrating radar
64:electromagnetic radiation
2721:. John Wiley & Sons.
2708:Jol, H. M., ed. (2008).
2391:. The Ganoksin Project.
1973:Robin, G. de Q. (1975).
1940:The Geographical Journal
947:10.1109/TAP.2013.2283604
897:10.2113/gssajg.109.3.301
808:. Ingenieurbüro obonic.
779:Ground Penetrating Radar
756:10.1109/TIM.2020.2984415
677:synthetic aperture radar
514:, imaginary part of the
40:Ground-penetrating radar
2680:Borchert, Olaf (2008).
2589:www.murphysurveys.co.uk
2347:Proceedings of the IEEE
2242:10.1126/science.aab0639
2185:10.1126/science.1122165
1679:. D. Reidel Publishing.
847:. Apollo 17 Experiments
228:archaeological features
226:it is used for mapping
106:electrical conductivity
1298:Historical Archaeology
1100:Archaeology in Oceania
526:resulting in low loss
383:Cowessess First Nation
379:Tk’emlúps te Secwépemc
325:
317:
262:electrical resistivity
216:nondestructive testing
188:
180:
36:
2014:Steenson, BO (1951).
1979:Journal of Glaciology
1825:10.5194/tc-7-375-2013
1763:10.5194/tc-7-499-2013
520:dielectric absorption
478:ice penetrating radar
363:University of Alberta
323:
314:
186:
178:
22:
2830:on 13 September 2018
2814:. 22 November 2011.
2618:. pp. 368–371.
2481:10.1049/cp.2013.0111
2300:10.1029/2006JE002745
1643:10.1029/2008GL035855
1573:Annals of Glaciology
1056:– via YouTube.
620:Similar technologies
522:of ice are small at
279:Vehicle localization
195:it is used to study
81:frequencies) of the
2868:Geophysical imaging
2540:2011IJSTA...4..763I
2291:2007JGRE..112.5S05S
2233:2015Sci...349b0639K
2176:2005Sci...310.1925P
2170:(5756): 1925–1928.
2127:10.2113/JEEG12.1.47
2119:2007JEEG...12...47B
1919:Drewry, DJ (1983).
1882:2004RPPh...67.1821D
1816:2013TCry....7..375F
1754:2013TCry....7..499B
1634:2008GeoRL..3524502K
1594:10.1017/aog.2020.11
1585:2020AnGla..61....1S
1271:1996Gearc..11..377C
1143:2010JGE.....7..190M
939:2013ITAP...61.6201H
889:2006SAJG..109..301W
777:Daniels DJ (2004).
748:2020ITIM...69.7422S
711:on 23 November 2021
2802:. 24 August 2009.
2662:. 30 December 2010
1310:10.1007/BF03376733
536:attenuation values
326:
318:
308:, and patterning.
189:
181:
37:
2751:978-0-7619-8927-1
2691:14, no. 4: 1047.
2633:978-1-4799-6789-6
2490:978-1-84919-603-1
2227:(6247): aab0639.
2029:Stern, W (1930).
1876:(10): 1821–1861.
1711:978-0-429-20642-9
1405:978-3-319-70890-4
1360:978-0-7619-8927-1
1112:10.1002/arco.5039
1017:10.1002/rob.21605
933:(12): 6201–6205.
788:978-0-86341-360-5
742:(10): 7422–7436.
679:units mounted on
652:Australian Police
524:radio frequencies
455:
454:
50:method that uses
2875:
2847:
2846:. 28 April 2021.
2839:
2837:
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2020:
2019:
2011:
2005:
2004:
1994:
1970:
1964:
1963:
1931:
1925:
1924:
1916:
1910:
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1492:
1477:
1471:
1470:
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1466:
1452:
1446:
1445:
1443:
1441:
1435:ArcGIS StoryMaps
1426:
1417:
1416:
1414:
1412:
1379:
1373:
1372:
1346:
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1334:
1332:
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1163:
1157:
1156:
1154:
1122:
1116:
1115:
1094:
1088:
1087:
1085:
1083:
1074:. Archived from
1064:
1058:
1057:
1055:
1053:
1036:
1030:
1029:
1019:
995:
986:
985:
974:
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821:
819:
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793:
792:
774:
768:
767:
727:
721:
720:
718:
716:
707:. Archived from
697:
607:Power regulation
504:portions of the
480:. It employs a
460:is the study of
450:
447:
441:
418:
410:
2883:
2882:
2878:
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2798:
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2779:
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2701:
2699:Further reading
2676:
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2430:
2426:
2413:
2412:
2408:
2398:
2396:
2387:
2386:
2382:
2339:
2335:
2330:. and 5 others.
2320:
2316:
2270:
2266:
2213:
2209:
2156:
2152:
2099:
2095:
2042:
2038:
2027:
2023:
2012:
2008:
1971:
1967:
1952:10.2307/1795099
1932:
1928:
1917:
1913:
1862:
1855:
1844:
1840:
1830:
1828:
1799:
1793:
1789:
1734:
1727:
1712:
1688:
1684:
1677:Radioglaciology
1673:
1669:
1614:
1610:
1564:
1557:
1504:
1500:
1490:
1488:
1479:
1478:
1474:
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1038:
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996:
989:
976:
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967:Birmingham Mail
966:
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907:
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728:
724:
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699:
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694:
689:
622:
609:
571:
554:
549:
548:
458:Radioglaciology
451:
445:
442:
431:
419:
407:
404:Radioglaciology
399:
355:
294:
281:
257:
173:
153:
141:hydrogeophysics
17:
12:
11:
5:
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2871:
2870:
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2777:External links
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2534:(4): 763–778.
2511:
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2380:
2353:(5): 837–857.
2333:
2314:
2285:(E5): E05S05.
2264:
2207:
2150:
2093:
2056:(3): 417–444.
2036:
2021:
2006:
1965:
1946:(4): 548–551.
1926:
1911:
1853:
1838:
1804:The Cryosphere
1787:
1748:(2): 499–510.
1742:The Cryosphere
1725:
1710:
1702:10.1201/b10155
1682:
1667:
1628:(24): L24502.
1608:
1555:
1498:
1487:. 23 June 2021
1472:
1447:
1418:
1404:
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1359:
1338:
1284:
1265:(5): 377–391.
1259:Geoarchaeology
1249:
1235:
1212:
1178:(9): 844–860.
1158:
1117:
1106:(3): 148–157.
1089:
1078:on 31 May 2017
1072:www.ll.mit.edu
1059:
1031:
987:
984:. 13 May 2020.
969:
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883:(3): 301–314.
858:
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674:ultra wideband
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506:radio spectrum
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193:Earth sciences
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91:permittivities
83:radio spectrum
60:nondestructive
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611:In 2005, the
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