Content uploaded by Maria S. Sudakova
Author content
All content in this area was uploaded by Maria S. Sudakova on Apr 01, 2019
Content may be subject to copyright.
219
ISSN 0145-8752, Moscow University Geology Bulletin, 2018, Vol. 73, No. 3, pp. 219–228. © Allerton Press, Inc., 2018.
Original Russian Text © M.S. Sudakova, M.L. Vladov, 2018, published in Vestnik Moskovskogo Universiteta, Seriya 4: Geologiya, 2018, No. 2, pp. 3–12.
Modern Directions of Application of Ground-Penetrating Radar
M. S. Sudakovaa, * and M. L. Vladova, **
aDepartment of Geology, Moscow State University, Moscow, Russia
*e-mail: m.s.sudakova@yandex.ru
**e-mail: vladov@geol.msu.ru
Received June 7, 2017
Abstract—Application of ground-penetrating radar in Russia has been addressed in the last decade not only
in scientific publications and production reports, but also in news media articles and TV plots on federal and
local channels. Three directions of using ground-penetrating radar that seem promising for the authors that
will be developed in the future are considered. These include georadar ray tomography, integration of ground-
penetrating radar with other geophysical methods, and the use of ground-penetrating radar for solving
geocryological problems. Examples of using different techniques of collection and processing of the data for
solving geological and technical problems are presented.
Keywords: electromagnetic tomography, integration of geophysical methods, pseudo–3D sur vey, permafrost rocks
DOI: 10.3103/S0145875218030109
INTRODUCTION
Approximately 10 years ago, the method of study-
ing a geological medium using a ground-penetrating
radar was technologically a new method in Russia. It
has gained enormous popularity. This method has
been addressed not only in scientific publications and
production reports, but also has been presented in the
news media articles and TV plots on the federal chan-
nels. The method has been considerably developed,
new procedures for information collection and pro-
cessing appeared or were adapted from the other areas,
laboratory studies that tie the parameters of ground-
penetrating radar data and the mechanical properties
and composition of the studied media were per-
formed, and the equipment was improved.
We focus on the directions that have been success-
ful for the development of ground-penetrating radar
surveying in the recent years and in our opinion, will
continue to increasing the accuracy of determining the
properties and the number of problems that can be
solved.
• Ground-penetrating radar tomography is a new
procedure for obtaining and processing data that was
borrowed from seismic survey. The performance of
measurements at different distances between a source
and a receiver, in particular, ground-penetrating radar
tomography, makes it possible to avoid the interpreta-
tion ambiguity that is typical of ground-penetrating
radar surveying. A tomography result is quantitative:
the values of electromagnetic wave propagation veloc-
ities are used not only to reveal so-called anomalous
zones, but also to determine the importance of layers
and the volumes of voids. The complication of the
procedure leads to a decrease in the survey efficiency
but increases the accuracy of determining both the
properties and sizes of the anomalies.
THE USE OF GROUND-PENETRATING
RADAR SURVEYING TOGETHER
WITH OTHER GEOPHYSICAL METHODS
Despite its popularity, ground-penetrating radar
surveying has not been included thus far in any typical
complex for solving geological problems. There are no
regulatory documents, or methodological guidelines
that could govern the use of ground-penetrating radar
as part of engineering-and-geological research. This is
an omission; therefore, here we consider the issue of
integration, the situations where ground-penetrating
radar can supplement or replace less-effective geo-
physical methods.
• Ground-penetrating radar surveys of a perma-
frost zone are relevant first of all due to the develop-
ment of the zone of permafrost rocks (PRs); the prob-
ability of global warming, the investigation of Mars,
and the development of new oil fields on the Arctic
shelf. The low electrical conductivity of permafrost
rocks contributes to successful use of ground-penetra-
tion radar because of the “increased” depth relative to
an unfrozen section. Studies performed in the winter
are relatively new here and the appearance of equip-
ment that has been operating steadily at low tempera-
tures contributes to the increase in their quantity.
220
MOSCOW UNIVERSITY GEOLOGY BULLETIN Vol. 73 No. 3 2018
SUDAKOVA, VLADOV
GROUND-PENETRATING RADAR
TOMOGRAPHY
The conventional modification of ground-pene-
trating radar application with zero source-receiver dis-
tance is the most cost-effective method and is less
time-consuming; it is consequently used most fre-
quently. However, the interpretation of the obtained
data is ambiguous in many cases and the information
on the internal structure of the studied medium is
qualitative in most cases. The switch from the qualita-
tive to the quantitative level is possible via ground-
penetrating radar tomography that uses a passing sig-
nal to obtain quantitative electromagnetic characteris-
tics at each point of the studied space.
The methods of ray tomography have become most
widespread in studying 3D velocity heterogeneities.
The process of solving the inverse problem of ray
tomography is the multiple solution of a direct prob-
lem and consists in selection of a velocity model of a
medium that satisfies the condition of the minimum
discrepancy between the observed and calculated
arrival times of waves at the receiving antenna. The
process of tomographic reconstruction is performed
special software (Reflexw, Geotom CG, etc.).
Due to the great attenuation of high-frequency
electromagnetic waves in a geological section, the dis-
tance between the boreholes that use ground-pene-
trating radar tomography is usually no greater than
10 m and the problems of inter-borehole ground-pen-
etrating radar surveying that are associated with the
state and properties of soils and rocks primarily have a
scientific character: imaging of tree roots (Butnor
et al., 2006), monitoring of quantity of water that pen-
etrates the soil and evaporates in the changing seasons
(Farmani et al., 2007), calculation of the water perme-
ability in the section (Tronicke et al., 2002), etc. The
sites of physical observations are found in the bore-
holes and/or on the surface; the boreholes use special
dipole antennas.
Ground-penetrating radar tomography gives prac-
tical results in nondestructive control of buildings and
engineering structures by using standard high-fre-
quency butterfly-type antennas (Fig. 1) for the search
for air-filled voids (Sudakova et al., 2017). Here, it is
used more successfully than the similar acoustic sur-
veys because an air void for electromagnetic waves is a
high-velocity anomaly, which first, provides a high
density of rays under Fermat’s principle, and second,
according to the procedure of ground-penetrating
radar surveying, a source or a receiver can move con-
tinuously, thus creating an arbitrarily large number of
rays (within a resolving power of the method) in con-
trast to acoustic tomography, where all sources and
receivers hold an assigned position.
The work (Wendrich et al., 2006) compared ultra-
sonic and ground-penetrating radar tomographies for
the detection of small voids (~20 × 10 cm) in a brick
wall. The errors in determining the air velocity as a
result of ultrasonic investigation (2500 m/s against the
actual 330 m/s) are much higher than for radar
(24 cm/ns against the actual 30 cm/ns). Unlike the
ground-penetrating radar results, such low accuracy
may make it difficult or impossible to detect and iden-
tify a velocity anomaly.
In (Sudakova et al., 2017), ground-penetrating
radar tomography was applied for imagery of a cavity
that covers ~20% of the column volume: here, the error
in velocity determination does not exceed 4 cm/ns and
for determination of the void area in plan view is no
greater than 2%. In addition to the cavity characteris-
tics, we also estimated the velocity of electromagnetic-
wave propagation inside the solid segment of the col-
Fig. 1. (A) A photo of the main building of Moscow State
University and (B) a tomographic section in the plane
shown by a white line. A Zond-12e ground-penetrating
radar, 1500 MHz and 2000 MHz antennas (Sudakova
et al., 2017). The location of the known void is designated
by a white square.
1.5
Y
X
30.000
27.770
25.550
23.320
21.100
18.870
16.650
14.420
12.12 0
9.975
7.750
5.525
3.300
1.4
1.3
1.2
1.1
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
0 0.25 0.50 0.75 1.00 1.25 1.50
Velocity, cm/ns
(a)
(b)
MOSCOW UNIVERSITY GEOLOGY BULLETIN Vol. 73 No. 3 2018
MODERN DIRECTIONS OF APPLICATION OF GROUND-PENETRATING RADAR 221
umn. The detailed distribution of the electromagnetic
wave velocity within the structure allows us to calcu-
late physical parameters, including humidity, poros-
ity, and strength, and holds great potential for ground-
penetrating radar tomography.
INTEGRATION OF GROUND-PENETRATING
RADAR WITH OTHER GEOPHYSICAL
METHODS
In the quantity and accuracy of the data, ground-
penetrating radar surveying is similar or surpasses seis-
mic surveying and outperforms all geophysical meth-
ods in the speed of obtaining information on a section,
in labor costs, and consequently, the costs of works. In
most cases, ground-penetrating radar is used together
with artificial geophysical methods: seismic survey
and electric exploration. It is difficult to find common
points for ground-penetrating radar with gravity and
magnetic surveys, nuclear physics, etc. with respect to
both the depth and sizes of the anomalies detected.
When integrated, a ground-penetrating radar can be
used for solving problems confined to the depths of
15–20 m, i.e., in engineering geology, geocryology,
glaciology, archaeological excavations, and engineer-
ing research.
Combined Use of Ground-Penetrating Radar
and Seismic Surveys
Ground-penetrating radar and seismic surveying
are two deterministic methods that use the ray approx-
imation. The temporary ground-penetrating radar and
seismic sections may be fully identical or differ in
detail due to the different natures of the field. The pro-
cedure of seismic surveying suggests the operation
with different distances between a source and a
receiver, which provides not only delineation of the
borders, but also estimation of their depth and identi-
fication by the velocity. The clear advantage of
ground-penetrating radar to seismic surveying is its
mobility, lower labor intensity, and the simpler proce-
dure of surveying. In planning an effective combina-
tion, it is expedient to perform seismic surveying opera-
tions at the reference segments for accurate mapping
and identification of ground-penetrating radar bound-
aries with respect to depth. The second advantage of the
ground-penetrating radar method is the shorter wave-
length, which enables one to characterize a section, for
example, to separate it into facies and to study the
internal structure of deposits and unevenness of
boundaries.
Figure 2 presents an example of effective integra-
tion of ground-penetrating radar and seismic survey-
ing using the method of refracted waves to study a sec-
tion of permafrost rocks (PRs) in the summer in the
area of the Kumzhin deposit in the Pechora River
delta (Sadurtdinov et al., 2016). The ground-penetrat-
ing radar section clearly shows a continuing series of
phase coincidence of axes in the reflected waves. To
obtain the data on the depth of major reflecting
boundaries and to identify them, we performed seis-
mic investigations on the typical segments of the pro-
file. We mapped the boundaries in the section that are
unambiguously identified by the velocities of seismic
waves as the roof of the PRs and the roof of the zone
of complete water saturation. The obtained data are
confirmed by the drilling data. In addition to the
boundaries mapped from the seismic data, the bottom
of oil contamination in sands is detected at a depth
throughout the entire ground-penetrating radar pro-
file; several boundaries can be identified at separate
segments of the profile in the thawed rock mass; the
reflection corresponding to a physical or lithological
boundary is recorded in the permafrost rock mass. As
a result, the integrated application of ground-pene-
trating radar and seismic surveys showed high effi-
ciency in studying the features of the geological sec-
tion and identifying the nature of the boundaries con-
sidered.
The Combined Use of Ground-Penetrating Radar
and Electrical Surveys
Ground-penetrating radar and electrical surveys
use the same f ield, but fundamentally different models
of its distribution in a medium: in most cases, electri-
cal surveying employs a quasi-stationary approxima-
tion, whereas ground-penetrating radar employs a ray
approach. In the case of a ground-penetrating radar,
there is no principle of equivalence, the dimensions of
an objec t in the georada r data depend only on its phys-
ical dimensions and geometry and do not depend on
the contrast of properties. When combined, ground-
penetrating radar can be used to determine the depth
of electromagnetic boundaries and dimensions of
local objects, in order to specify the values of resistivity
obtained from the electrical survey data.
The work (Elsayed et al., 2014) presented an exam-
ple of the integrated application of electrical resistivity
tomography and ground-penetrating radar surveying
for the search for archaeological objects in the territory
of the Old Luxor monument (Egypt) behind the so-
called “singing” statues of Memnon. According to the
results of electrical resistivity tomography, a high-
resistivity anomaly (up to 2000 Ω m) is imaged on sev-
eral neighboring profiles at the studied ~150 × 150 m
segment, which can be interpreted as a buried archae-
ological object (Fig. 3a). At the second stage of inves-
tigation, ground-penetrating radar surveying was per-
formed for a dense profile network (a total of 81 pro-
files) in a region with a high-resistivity anomaly of
40 × 30 m. As a result, a diffraction object with a typ-
ical “clinking” record was detected and a 20 × 30 m
anomalous zone that was found by electrical surveying
was reduced to 3 × 2 m (Fig. 3b). A 130-m-high statue
of a pharaoh with a hippo’s head was found on this
segment at a depth of ~3 m. The large contrast in the
222
MOSCOW UNIVERSITY GEOLOGY BULLETIN Vol. 73 No. 3 2018
SUDAKOVA, VLADOV
resistivity of the alabaster of the statue and the host soil
caused the excess in the size of the anomaly on the
electrical resistivity tomography image cross-sections
over the size of its source by more than an order of
magnitude. The problem was solved using ground-
penetrating radar, which made it possible to locate the
archaeological object in plan and in depth; thus, the
volume of archaeological work was considerably
decreased.
Combined Application of Seismic Surveying,
Ground-Penetrating Radar, and Gravity Surveying
The scientific work (Hausman et al., 2007)
describes an infrequent integration of ground-pene-
trating radar, gravity, and seismic surveying. The task
was to construct a model of a glacier in the Austrian
Alps (the city of Innsbruck), including its structure,
thickness, ice content, and density in order to calcu-
late the velocity of its movement.
According to the results of seismic surveying, three
layers were identified in the medium (Fig. 4, model М0):
the upper weathered layer (a velocity of longitudinal
waves of 950 m/s), the body of the glacier with a veloc-
ity of longitudinal waves of 3100–3500 m/s and the
bottom layer, which is represented by the rocky base of
the glacier composed of weathered gneisses with a
velocity of 4100 m/s. The georadar studies showed the
occurrence of a “strong” R1 reflector, that is, the
reflection from the water layer beneath the glacier.
There was a considerable discrepancy in the depth of
the imaged boundaries from the seismic survey data
and the R1 reflector. According to the seismic explo-
rations performed according to the t0 method, the
thawed layer cannot be distinguished: a “lost-layer”
effect occurs. A new four-layer model was constructed
taking the ground-penetrating radar and seismic sur-
vey data into account; it included a layer with a veloc-
ity of 1500 m/s, whose roof coincided with the posi-
tion of the R1 boundary with a slight error. This four-
Fig. 2. Deep sections: (a) by a ground-penetrating radar with interpretation and (b) seismogeocryological. A 300 MHz antenna,
a Zond-12e georadar: (1) the boundary of contamination in sands; (2) the level of ground water; (3) the roof of permafrost rocks
(PRs); (4) the boundary in the PR stratum according to (Sadurtdinov et al., 2016).
Distance, m
Depth, m
Aeration zone
Vp0 = 350 ÷ 400 m/s
VpZCWS = 1650 m/s
VSH0 = 220 ÷ 230 m/s
VSHDS = 1750 m/s
VSH0 = 220 ÷ 230 m/s
Zone of complete
water saturation
Roof of permafrost
rocks
(a)
(b)
1
200 210 220 230 240 250 260 270 280 290 300 310
0
2
4
6
8
10
Depth, m
0
2
4
6
8
10
12
14
2
3
4
210 220 230 240
MOSCOW UNIVERSITY GEOLOGY BULLETIN Vol. 73 No. 3 2018
MODERN DIRECTIONS OF APPLICATION OF GROUND-PENETRATING RADAR 223
layer structural model of the glacier was used for filling
it with gravimetric information on the density of the
layers, content of pure ice in the glacier, and construc-
tion of the composite geological-geophysical cross-
section (Fig. 4c). Using the Glenn formula, the veloc-
ity of glacier movement was estimated at ~3 m per
year, which was equal to that one calculated earlier by
the air and satellites photographs.
Each method was necessary to determine the inde-
pendent characteristics of the glacier that together
helped solve the complicated geological problem.
STUDYING THE PERMAFROST ZONES
USING A GROUND-PENETRATING RADAR
The region of permafrost rocks (PRs) occupies a
broad area of our planet. Almost 40% of the dry land
and shelf is covered by the cryolitic zone. In Russia, it
takes up ~65% of the territory, including many major
mining, oil, coal, and other areas of prospecting,
development, and extraction of minerals. This puts
forward the study of frozen rocks and ices into the
number of the most crucial scientific and practical
global problems. There are not only scientific goals
related to the study and monitoring of permafrost
rocks, but also a set of practical problems caused by
construction and laying of roads and pipelines, drilling
of exploratory and production wells in the zone of per-
mafrost rocks development, etc. In the recent decades,
permafrost degradation resulting from global climate
change has been an issue.
When the rock temperature passes through 0°С,
deep quality transformations occur and physical and,
consequently, geophysical properties change. In par-
ticular, conductivity drops by several orders of magni-
tude, while dielectric permeability decreases by a few
times.
Due to the differences in the electric properties of
ice, water, air, and soil, ground-penetrating radar can
be successfully used in studying the upper 30 m of the
cryolitic zone section; in some cases, this layer can be
thicker if the frequency decreases. The boundary of
the water-phase transition is very contrasting for high-
frequency electromagnetic waves; due to the isolating
properties of ice, an electromagnetic signal penetrates
at great depth with small losses.
A ground-penetrating radar is applied in the area of
the cryolitic zone to successfully solve problems
related to the location of the frozen-thawed zone
boundary and its monitoring. In most cases, these
works address mapping of the roof of permafrost
rocks, which is consistent with high-amplitude reflec-
tion, below which no continuous reflectors are
recorded. In addition to the problems of mapping,
ground-penetrating radar can be used for the search of
local objects, e.g., frozen mammoths (Makino and
Miura, 2005).
Fig. 3. (a) The result of electrical resistivity tomography and (b) a radargram obtained on the central part of the profile. A Sir–2000 geo-
radar with a 200 MHz antenna was used (Elsayed et al., 2014).
0 24
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
48 72 96 120 14 4 m
Depth, m
Distance, m
0.750
3.82
7.46
11. 9
17. 2
20.3
23.6
0 0
1
2
3
4
5
6
7
8
9
20
40
60
80
100
120
140
160
180
(a)
Time, ns
Depth at a velocity of 10 cm/ns
(b)
0.262 0.922 3.25 11.4 40.3 142 501 1764
Layer 1 Layer 1 Layer 1 Layer 1 Layer 1
Layer 2 Layer 2
Layer 2
Anomaly
Resistivity, Ω m
224
MOSCOW UNIVERSITY GEOLOGY BULLETIN Vol. 73 No. 3 2018
SUDAKOVA, VLADOV
When space programs on the study of Mars began,
a role of ground-penetrating radar for them was dis-
cussed, where the major goal of its application is the
search for water in a frozen state. Terrestrial perma-
frost rocks can be studied as an analog of works on
Mars for testing special equipment (Berthelier, 2003).
In most cases, geocryological problems are solved
when a ground-penetrating radar method is integrated
with electrical surveying methods (Fortier, 2010), less
frequently, when it is combined with seismic surveying
(Sadurtinov et al., 2016).
The restrictions for ground-penetrating radar do
not depend on where it is used. It is difficult or impos-
sible to determine the location of the active layer base
in the case it is represented by soils with increased con-
ductivity, that is, clayey or saline soils. The boundary
of the frozen–thawed zone in the area of island per-
mafrost may have a complex 3D form; therefore, the
Fig. 4. (a) Glacier models: seismic (М0) and plotted with respect to the joint interpretation by the ground-penetrating radar and
seismic surveys (М1). An example of radargrams on one of the profiles performed along the glacier. (b) A Sir–2000 ground-pen-
etrating radar and a 35 MHz antenna. (c) Integrated geological-geophysical profile of the glacier from the data of seismic survey,
ground-penetrating radar, and gravimetric survey (Hausman etc., 2007).
0
10
20
30
40
Velocity, m/s
Depth, m
Surface moraine
1000 2000 3000
(a)
Thawed layer
Glacier’s base
M1
MO
Permafrost rocks
with high
ice content
R1
010 20 30 40 50 60 70 80 90 100 110 120 13 0 17 0140 150 160 18 0
Distance, m
N
N
Old layer roof
Glacial base (seismic survey)
Permafrost rocks with high
53%(39%)ice content (gravimetric survey)
S
S
R1R1R1
0 0
10
20
30
40
50
60
70
80
100
300
200
400
500
700
800
800
900
1000
110 0
Time, ns
Depth, m
(b)
2360
2400
(c)
53%(39%)
56%(42%)
66%(52%) 59%(45%)
360270198 Distance, m
Elevation, m
(ground-penetrating radar)
ice content (seismic survey)
MOSCOW UNIVERSITY GEOLOGY BULLETIN Vol. 73 No. 3 2018
MODERN DIRECTIONS OF APPLICATION OF GROUND-PENETRATING RADAR 225
interpretation of the data obtained in the area of island
permafrost may require additional information. Many
works in the area of permafrost rocks have been non-
trivial for ground-penetrating radar thus far. In partic-
ular, these include 3D (or pseudo-3D) survey and
mapping the boundaries of phase transition, evalua-
tion of humidity in an active layer and ice content in
frozen rocks, and monitoring of changes in physical
properties. Winter works are performed infrequently.
However, taking the great depth in the winter into
account (when a “strong” boundary such as a thawing
base is absent), ground-penetrating radar could be
used to locate the permafrost base.
Inclusion of ground-penetrating radar surveying
into the obligatory set of studies would considerably
simplify the determination of the thickness of the
active layer at scientific stations, where this is done at
present using direct methods (with a probe), as in in
the previous century, and would significantly expand
the monitoring scope, where due to a great depth of
thawing, it can’t be done with a probe or by drilling
using a fine grid.
Search for Regions with Increased Ice Content
The work (De Pascale et al., 2008) describes the
search for regions with increased ice content in loams
in the winter; its authors focused attention on the
advantages of searching in the season of negative tem-
peratures when not only are the energy losses lower,
but the surface where the researchers and equipment
move is also harder. This work presents an example of
integration of ground-penetrating radar and electrical
surveys; the authors note that the equipment operated
steadily until –40°С. The obtained radargrams show
the regions of increased amplitude that correspond to
regions of increased resistivity and can be confidently
interpreted as massive ice or regions with increased ice
content. At the segments of the sections where the
decreased values of resistivities were recorded, the
amplitude anomalies are absent. Here, a typical
decrease in the topography is observed. According to
all indications, this region of subsidence resulted from
thawing (a thermokarst) in the previous geological
epoch.
Estimation of the Humidity in the Active Layer
Control of water content in soil using direct meth-
ods, including direct gravity measurements, is labori-
ous; it provides the values of humidity only at separate
points of the medium and characterizes only the near-
surface layer. Dielectric permeability is a function of
water content; therefore, the temporal and lateral
changes in soil humidity can be found using ground-
penetrating radar. To do this, we need to know the
velocity of electromagnetic-wave propagation, which
can be recalculated later to volume humidity using an
appropriate correlation dependence. The work (Suda-
kova et al., 2017) compared the maps of volume
humidity in the active layer obtained from the ground-
penetrating radar data and gravimetric humidity in the
near-surface layer at a depth of 20 cm measured by the
gravity method (Fig. 5). At the segment of the works, the
thickness of the active layer varies from 20 to 140 cm.
The typical segments of high and low humidity
almost coincide: on both maps, the northwestern part
of the segment is characterized by the highest values of
humidity. The values of the volume humidity are
greater than those of the gravimetric humidity, which
is correct in principle, since gravimetric humidity
characterizes only the near-surface layer, and that
Fig. 5. Maps of the humidity for an active layer. (a) Gravimetric humidity, direct observations, depth of 20 cm and (b) volume
humidity (the result of using ground-penetrating radar, a depth of 20–140 cm) (Sudakova et al., 2017).
(a)
0 102030405060708090 100
90
80
70
60
50
40
30
20
10
90
80
70
60
50
40
30
20
10
0
(b)
0 102030405060708090 100
90
80
70
60
50
40
30
20
10
90
80
70
60
50
40
30
20
10
0
226
MOSCOW UNIVERSITY GEOLOGY BULLETIN Vol. 73 No. 3 2018
SUDAKOVA, VLADOV
obtained from the ground-penetrating radar data
describes the entire active layer, including the zone of
complete water saturation. The similarity of the
humidity maps constructed based on the ground-pen-
etrating radar data and from direct observations shows
the expedient use of a ground-penetrating radar for
evaluation of aerial variation in rock humidity in a
thawed layer. In this case, we can avoid direct mea-
surements of gravimetric humidity in the near-surface
layer or decrease their volume.
Application of 3D Visualization
In some cases, 3D visualization of ground-pene-
trating radar data can significantly facilitate interpre-
tation and analysis of structural and stratigraphic fea-
tures of a studied medium. For 3D imaging, relatively
small areas (from 5 to 50 m2) are covered by a network
of closely-located (as a rule, from 0.2 to 1 m) parallel
ground-penetrating radar profiles. The dense network
of profiles is necessary for accurate imaging of the
geometry and the sizes of different features of the sec-
tion and a decrease in ambiguity and the probable
appearance of artefacts related to incorrect interpola-
tion. When the data of pseudo-3D surveying are inter-
preted, the amplitude features on the horizontal plane
are analyzed; these indicate the changes in soil prop-
erties or occurrence of some characteristics of a sec-
tion (discontinuities, unconformities, local objects,
inclusions, etc.).
The work (Munroe et al., 2007) presented an
example of using a pseudo-3D survey to determine the
spatial-depth location of polygonal-wedge ices in
Alaska. Its authors noted that the ice wedges covered
under a vegetation layer cannot be identified on 2D
radar profiles; in this research, the methods of 3D
Fig. 6. (a) A photo of a wedge-shaped ice vein and the view of the region of polygonal-wedge ices (PWI) at the top. The 3D data
cube obtained at the PWI segment. A Sir–3000 ground-penetrating radar and a 400 MHz antenna. The average velocity in the
section is 13 cm/ns. (b) The distance is plotted along the axes in meters (Munroe etc., 2007).
(a) (b)
(b)
0
1
2
40
30
20
10
0
m/m
10 20 30 40
MOSCOW UNIVERSITY GEOLOGY BULLETIN Vol. 73 No. 3 2018
MODERN DIRECTIONS OF APPLICATION OF GROUND-PENETRATING RADAR 227
visualization helped to reduce interpretation uncer-
tainty and define the geometry of the network of ice-
wedge occurrence.
The works were performed in the winter to decrease
attenuation in the near-surface layer. Figure 6 presents
a data cube obtained at one of the segments under
study. The 2D profiles shows the section structure: the
first axis of phase coincidence at the top corresponds
to the bottom of the snow cover; the next one corre-
sponds to the bottom of the organic layer. Under-
neath, a layer of sand lacustrine deposits occurs that is
characterized by a wave pattern with subhorizontal or
weakly inclined axes of phase coincidence. The pres-
ence of a set of diffraction hyperbolas in the bottom
part of the radargrams indicates a large amount of
gravel material at the base of this layer. The interpreta-
tion results are confirmed by the data of drilling that
was performed to a depth of 110 cm. For 2D sections,
the ice veins and wedges are not identified; however,
for the sections in the horizontal plane, the boundaries
of the polygons, that is, reflections from ice wedges
(black stripes) are clearly seen.
This example illustrates the successful use of 3D
ground-penetrating radar surveying to solve the prob-
lem of imaging of ice structures in the near-surface
layer under the conditions of a cryolitic zone.
CONCLUSIONS
The ground-penetrating-radar method has been
steadily developing towards refinement of the proce-
dure for collection and processing of data to obtain
information on not only the section structure, but also
on the distribution of its electromagnetic and mechan-
ical properties.
Whether ground-penetrating radar is a major or
auxiliary method in a set of geophysical investigations,
the proper arrangement of the procedure makes the
entire set more effective or it becomes fully successful
due to it. In the problems where a greater depth is
required, ground-penetrating radar can be used for the
detailed study of the upper part of the segment.
To solve the problems of studying a cryolitic zone,
it is quite expedient to use a ground-penetrating radar
as a major or additional tool for studying engineering–
geocryological conditions. Compared to other geolog-
ical or geophysical methods, ground-penetrating
radar surveying allows imaging of the geometry of geo-
logical boundaries, the section structure, and physical
properties in more detail.
The method of ground-penetrating radar tomogra-
phy has been developed for nondestructive control,
which helps one to obtain data not only on the pres-
ence and sizes of voids, but also on the physical prop-
erties of an object. The information obtained using
ground-penetrating radar tomography is more reliable
than that obtained during the work with a coupled
source and receiver. The results of these studies
allowed us to conclude that the ground-penetrating
radar method should be used during the reconstruc-
tion and repair of structures to provide safe operation
of industrial facilities and civilian objects.
REFERENCES
Berthelier, J.J., Ney, R., Ciarletti, V., Reineix, A., et al.,
GPR, a ground-penetrating radar for the Netlander mis-
sion, J. Geophys. Res., 2003, vol. 108, no. 4, pp. 5–18.
Butnor, J.R., Johnsen, K.H., Lundmark, T., et al., Imaging
tree roots with borehole radar, 11th Int. Conf. on Ground
Penetrating Radar, June 19–22, 2006, Columbus Ohio,
USA. Columbus Ohio, 2006.
Elsayed, I.S., Alhussein, A.B., Gad, E., and Mahfooz, A.H.,
Shallow seismic refraction, two-dimensional electrical
resistivity imaging, and ground penetrating radar for
imaging the ancient monuments at the western shore of
old Luxor city, Egypt, Archaeological Discovery, 2014,
no. 2, pp. 31–43.
Farmani, M.B., Keers, H., and Kitterod, N.-O., Time-
lapse GPR tomography of unsaturated water f low in an
ice-contact delta, Vad o s e Z o n e J., 2007, vol. 6, no. 4,
pp. 1–12.
Fortier, R. and Savard, C., Engineering geophysical investi-
gation of permafrost conditions underneath airfield
embankments in Northern Quebec (Canada), Proc.
Conf. Geo 2010, Calgary: Canada, 2010, pp. 1307–1316.
Hausmann, H., Krainer, K., Bruckl, E., and Mostler, W.,
Internal structure and ice content of Reichenkar rock
glacier (Stubai Alps, Austria) assessed by geophysical
investigations, Permafrost and Periglacial Processes,
2007, no. 18, pp. 351–367.
Makino, K.-I. and Miura, H., Location of Mammoth
remains in permafrost of Northern Siberia using GPR
and multifrequency EM, 18th EEGS Symp. on the Appli-
cation of Geophysics to Engineering and Environmental
Problems. Extended Abstract. 2005.
Munroe, J.S., Doolittle, J.A., Kanevskiy, M.Z., et al.,
Application of ground penetrating radar imagery for
three-dimensional visualisation of near surface structures
in ice-rich permafrost, Barrow, Alaska, in Permafrost and
Periglacial Processes, 2007. www.interscience.wiley.com.
doi 10.1002/ p.59410.1002/ p.594
De Pascale, G.P., Pollard, W.H., and Williams, K.K., Geo-
physical mapping of ground ice using a combination of
capacitive coupled resistivity and ground-penetrating
radar, Northwest Territories, Canada. J. Geophys. Res.
Earth Surface (2003–2012), 2008, vol. 113, no. F2,
no. 1–15.
Sadurtdinov, M.R., Malkova, G.V., Skvortsov, A.G., et al.,
The current state of insular permafrost in the Pechora
River floodplain (Nenets Autonomous Okrug) based
on the results of integrated geocryological and geophys-
ical surveys, in Mater. 5-i Konf. geokriologov Rossii
“Geotekhnika v kriolitozone” 14–17 iyunya 2016, MGU,
Moskva (Proc. 5th Conf. Geocryologists of Russia
“Geotectonics in Cryozone”, June 14–17, 2016, MSU,
Moscow), Moscow, 2016.
228
MOSCOW UNIVERSITY GEOLOGY BULLETIN Vol. 73 No. 3 2018
SUDAKOVA, VLADOV
Sudakova, M.S., Kalashnikov, A.Yu., and Terentieva, E.B.,
Studying the possibilities of georadar tomography in
searching for air cavities in engineering constructions,
Russ. J. Nondestructive Testing, vol. 52, no. 9, 2016,
pp. 520–527.
Sudakova, M.S., Terentieva, E.B., and Kalashnikov, A.Yu.,
Searching and measurement of functional voids by
means of GPR tomography by the example of two col-
umns, Int. J. for Computational Civil and Structural
Engineering, 2017, vol. 13, no. 1, pp. 94–109.
Sudakova, M.S., Kalashnikov, A.Yu., Vladov, M.L., et al.,
Detection of voids in engineering structures using GPR
method, Geotekhnics, 2017, no. 2, pp. 30–37.
Sudakova, M.S., Sadurtdinov, M.R., Skvortsov, A.G.,
et al., Ground penetrating radar applications to perma-
frost investigations, Kriosfera Zemli, 2017, vol. 21, no. 3,
pp. 62–74.
Tronicke, J., Dietrich, P., Wahlig, U., and Appel, E., Inte-
grating surface georadar and crosshole radar tomogra-
phy: a validation experiment in braided stream depos-
its, Geophysics, 2002, vol. 67, no. 5, pp. 1516–1523.
Wendrich, A., Trela, C., Krause, M., et al., Location of
Voids in Masonry Structures by Using Radar and Ultra-
sonic Traveltime, Berlin: ECNDT, 2006.
Translated by L. Mukhortova
SPELL: 1. OK
