The LOZA uses for various purposes such as search for hydrogeological objects, paleo- reliefs, kimberlite pipes and fissures, voids in the underlying medium, and geological structures. Some experiments with the DPR were carried out in South Africa in 2018 where traditionally GPR were used only for mine exploration.

1. Abstract, 24th
EM Induction Workshop, Helsingør, Denmark, August 12-19, 2018
1 / 4
Geo-radar LOZA and it application for sounding high resistive sections in South
Africa
A.Berkut1
, P. Morozov2
, N.Uliantszev1
and Hallbauer-Zadorozhnaya3
V.
Stettler E.Co-author4
1
LOZA RADAR (VNIISMI Co). Moscow, Russia, lozaberk@yandex.ru
2
Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation, Moscow, Russia,
pmoroz5@yandex.ru
3
Tshwane University of Technology, Pretoria, South Africa, valeriya.hallbauer@gmail.comn, email contact
4
University of Witwatersrand, Johannesburg, Soutrh Africa,
Keywords: deep ground penetrated radar, dielectric permeability, modeling, kimberlite pipe
INTRODUCTION
The LOZA is the ground penetrated radar
developed and manufactured in Russia (LOZA
RADAR (VNIISMI Co). The LOZA can be used for
small depth but also can reach large depths in wet
soils to delineate low- contrast geological
boundaries: (deep penetrated radar, DPR).
Distinctive features of the LOZA are: enhanced
pulse power, signal energy concentration in the low
part of the frequency band, large dynamic range of
registered echo signals. The DPR allows study
subsurface media and structures previously not
accessible another types of GPR. The LOZA is of
non-invasive instrument and have been
successfully used in the numerous countries
(Russia, Australia, Egypt, USA, UK, Kazakhstan,
Chili etc). The LOZA uses for various purposes
such as search for hydrogeological objects, paleo-
reliefs, kimberlite pipes and fissures, voids in the
underlying medium, and geological structures.
Some experiments with the DPR were carried out in
South Africa in 2018 where traditionally GPR were
used only for mine exploration.
The radar LOZA
Main technical characteristics of standard Loza-N
DPR are:
- Receiver frequency band is 1-50 MHz;
-. Antennas: resistively loaded half-wavelength
dipoles of Wu-King type, central frequencies from
25 MHz (6 meter) to 50 MHz (3 meter long);.
- . Transmitter voltage supplied to antenna are 10
and 21 kV;
-. Pulse repetition rate: 150-200 1/s.
- Radar potential (max transmitted over min
received signal) is not less than 120 dB.
The sketch of the radar LOZA is shown in the
Figure 1.
Figure 1. The sketch of the radar LOZA
Transmitter. Peak power reaches practical limit
allowed by insulating properties of surrounding
matter. Power pulse has generated by a gradually
loaded capacitor, rapidly discharging through a
high-voltage hydrogen key. Pulse’s duration and
shape depend on antenna parameters. Example of
the power pulse is presented in the Figure 2.

2. Abstract, 24th
EM Induction Workshop, Helsingør, Denmark, August 12-19, 2018
2 / 4
Figure 2. Shape of power pulse.
Antennas. Both transmitter and receiver antennas
are non-resonant in order to avoid spurious
“ringing”. Wu-King resistive loading principle is
used, it means energy dissipation gradually
increasing resistors between linear antenna
elements. Both antennas keeping apart (depending
of depth of investigation (Figure 3.)
Figure 3. Field work, antennas keeping 3 m apart.
Frequency band. To reach maximum depth, pulse
spectrum in LOZA-N DPR is shifted to the lower
part of receiver frequency band to 1-50 MHz. Serial
LOZA-N SYSTEM contains 50 MHz (3 m long), 25
MHz (6 m), 15 MHz (10 m) and 10 MHz (15 m)
resistively-loaded antennas mounted on a heavy-
duty nylon band.•.
Receiver, signal digitization. Receiver is a central
unit of the LOZA-N. It registers amplitudes using a
parallel set of high-rate comparators with sampling
frequency: 0.5-1 GHz. By repeating measurements
with input attenuation changing in quasi-logarithmic
scale, LOZA-N processor obtains 256-bit signal
representation in 120 dB dynamic.
Physical theory of deep GPR echoes.
Analytical theory of quasi-1D wave propagation,
based on time-domain version of coupled the
Wentzel-Kramers-Brillouin (WKB) approximation
[1] explains weak backward scattering from
smoothly stratified subsurface medium. The initial
pulse travels from the earth surface z = 0. In
particular, the half-space response to the input
electromagnetic pulse is [2]:
𝑔(𝑠) = −
1
4
∫
𝜀1(𝑧)
𝜀(𝑧)
𝑓[𝑠 − 2 ∫ √𝜀(𝜁)𝑑𝜁
𝑠
0
]
𝑍(𝑠)
0
𝑑𝑧 , (1)
where 𝑓(𝑠) is an initial pulse which travels from
the earth surface ( 𝑧 = 0), than according the
geometrical optics low it reflects from the gradient
𝜀1
(𝑧)/𝜀(𝑧)’ and returns back covering optical path
𝑝(𝑧) = 2 ∫ √𝜀(𝜁)𝑑𝜁
𝑧
0
. Note that 𝜀 is relative
permittivity (dimensionless). The return signal g(s)
produced by partial reflections of the initial EM
pulse 𝑓(𝑠) = 𝑑ℎ(𝑠)/𝑑𝑠 from the gradually varying
dielectric permittivity. Equation (1) is a sum of
partial reflections due to the permittivity gradients, it
can be considered as an integral equation for the
unknown function 𝜀(𝑧). For mathematical
modeling the function 𝜀(𝑧) which can be
presented as example as the function:
𝜀(𝑧) =
𝜀0 + 𝜀1
2
−
𝜀0 − 𝜀1
2
𝑒𝑟𝑓 [
2𝑧 − 𝑧0 − 𝑧1
𝜎(𝑧1 − 𝑧0)
], (2)
The parameters of (2) is shown in the Figure 5.
Figure 4. Geometry of the simulated scenario and
schematic representation of the radar signal
components. aw is a air wave, gw is a direct
(ground) wave, iw is the incident wave, impinging
on the transition layer, rw and tw are the waves
reflected and transmitted by the transmitted layer
respectively.
Example of function described relative chargeability
is shown in the Figure 6a as well as a theoretical
signal for this law of chargeability distribution
(Figure 6b). In the Figure 6c is presented the real
field data and mathematical modeling using (1) and
decreasing 𝜀(𝑧)as shown in the Figure 6a.

3. Berkut A. et al., 2018, Short title comes here …
Abstract, 24th
EM Induction Workshop, Helsingør, Denmark, August 12-19, 2018 3 / 4
a
b
c
Figure 6. Model of vertical distribution of relative
dielectric permeability (a), received signal in
quasi-logarithmic scale (c) and mathematical
modeling using (1).
RESULTS AND DISCUSSION
Experiments with the deep geo-radar LOZA have
been carried out in high resistive settlements in
South Africa for different purposes. The LOZA N
has been used. The frequency band is 1-50 MHz,
transmitter power 10 kW, length of antennas are
3m (50 MHz), distance between the antennas is 3
m, accuracy of the receiver (sensitivity? Noise
level? ) is 100 𝜇𝑉, time interval 512𝑛𝑠, time step
(discretization) 1𝑛𝑠 distance between reading is 40
cm.
1. Paleoriver. Figure 7 demonstrates the
radiogram along the profile crossing a paleoriver.
The altitudes of the reading are taking account.
Figure 7. Geo-radar crossing the paloeriver.
The paleoriver strongly observes between 154 -273
m (right part of profile, blue and purple colour), the
borders of the paleoriver are vertical. The bottom of
the paleoriver is located at the depth of about 45 m.
An old alluvial diamonds takes place 200-300 m
away (Figure 8). It is possible that the observed
object is a part of the complicate paleoriver system
wildly distributed in the Nord West province in
South Africa. .
Figure 8. Plan of the profile located close to the old
alluvial mine.
Void. The target is to define a possible void in an
old and partially destroyed mine. According to the
LOZA N data a void is observed along the profile
between stations 40-48 m at the depth 12-13 (black
ring). The anomaly is very contrast compare to
surrounding rocks.

4. Berkut A. et al., 2018, Short title comes here …
Abstract, 24th
EM Induction Workshop, Helsingør, Denmark, August 12-19, 2018 4 / 4
Figure 9. Void is observed at the depth 12-13 m.
Kimberlite pipe. The kimberlite pipe was observed
in ………area in South Africa. It is known by drilling
pipe and was found at the depth of 65 m. However
it take 30 minutes for fieldwork and in the screen of
the instrument LOZA N the shape of this pipe was
discovered.
Figure 10. Kimberlite pipe discovered using the
LOZA N. Shape of kimberlite pipe is shown by red
colour.
Interpretation of the radar data showed very
contrast local object with sub vertical borders. Objet
locates between 30 and 140 m of profile. Top
surface of this object is covered by 60 m layered
sediments. Amplitudes and phases of this object
showed the highest values of dielectric permittivity
𝜀 and conductivity 𝜎 than surrounding rocks.
In the Figure 12 is shown a kimberlite observing in
Australia in 2016 which has the same shape as
described above. .
Figure 11. Kimberlite pipe in Australia
CONCLUSIONS
New principles of Loza GPR series allows to reach
electromagnetic wave penetration to depth up to
100-200 m. New features of the weak echo signals
coming from these depths can be interpreted using
a time-domain version of coupled WKB theory.
Experiments with geo-radar LOZA in South Africa
showed good results for searching several object
hiding in high resistive surroundings. We delimited
a paleoriver, the void in old partially destroyed mine
and kimberlite pipe. We expect that the instrument
LOZA N surely steps into the country
References
Bremmer H (1958) Propagation of Electromagnetic
Waves, Handbuch der Physik / Encyclopedia of
Physics, v. 4/16, pp. 423-639. Springer
Prokopovich I, Popov A, Pajewski L, Marciniak M
(2018) Application of coupled-wave Wentzel-
Kramers-Brillouin approximation to ground
penetrating Radar. Remote Sens. 2018, 10, 1-20;
doi:10.3390/rs10010022 ID