Page 1 of 14

European Journal of Applied Sciences – Vol. 12, No. 3

Publication Date: June 25, 2024

DOI:10.14738/aivp.123.17043

Solarić, N., Solarić, M., Barković, Đ, Zrinjski, M., Bogdanovski, Z., Dimevski, S., & Postalovski, A. (2024). On the Method of

Analysis for Earthquake Forecasting. European Journal of Applied Sciences, Vol - 12(3). 324-337.

Services for Science and Education – United Kingdom

On the Method of Analysis for Earthquake Forecasting

Nikola Solarić

Geodetski fakultet, Zagreb, Hrvatska

Miljenko Solarić

Geodetski fakultet, Zagreb, Hrvatska

Đuro Barković

Geodetski fakultet, Zagreb, Hrvatska

Mladen Zrinjski

Geodetski fakultet, Zagreb, Hrvatska

Zlatko Bogdanovski

Civil Engineering Skopje, S. Makedonija

Sasha Dimevski

Civil Engineering Skopje, S. Makedonija

A. Postalovski

Civil Engineering Skopje, S. Makedonija

Keywords: GNSS (are global navigation satellite system), and there are several types:

GPS, GLONAS, GALILEO, KOMPAS), GPS (USA Global Navigation system), GLONASS

(Russian Global Navigation Satellite System), GALILEO (European global navigation

system, COMPAS (Chinese global navigation system)

INTRODUCTION

Today, larges and compressions of terrain can be measured very precisely using satellites of

the GNSS (global navigation satellite system). GNSS consists of GPS (USA) (Fig. 1.), GLONASS

(Russian), GALILEO (European), and COMPAS (Chinese) system. GPS global positioning

system) satellites orbit (Fig.2.) the Earth at an altitude of 20,200 km from the Earth’s surface

in six orbital planes, so that the GPS receiver on Earth can always receive signals from at least

four satellites.

Page 2 of 14

325

Solarić, N., Solarić, M., Barković, Đ, Zrinjski, M., Bogdanovski, Z., Dimevski, S., & Postalovski, A. (2024). On the Method of Analysis for Earthquake

Forecasting. European Journal of Applied Sciences, Vol - 12(3). 324-337.

URL: http://dx.doi.org/10.14738/aivp.123.17043

Fig 1: GPS (USA)

Fig 2: Trajectories of GPS satellites 20,200 km above the surface of the Earth in 6 orbital planes

so that the GPS receiver on Earth can always receive signals from at least 4 of the satellites.

Fig 3: Precise GPS antenna Zephyr usually on the roof cadastre building. 24 hours/day

By measuring the time of the signal from the satellite to the antenna, the GNSS satellites

coordinates of the antenna aired determined.

Page 3 of 14

Services for Science and Education – United Kingdom 326

European Journal of Applied Sciences (EJAS) Vol. 12, Issue 3, June-2024

3 lengths and a clock correction in the receiver are calculated from the time measurement.

antenna coordinates are calculated by arc section 3 length.

GPS satellites transmit radio signals, and at the moment of transmitting the signal, the satellite

writes the time of the signal on the atomic clock in the satellite and the number of the satellite

that sent the signal. When the signal reaches the Earth to the antenna, the receiver writes the

time from the electronic clock in the receiver into that signal. The distance to the satellite can

be calculated from the time of receiving the signal and the time of sending the signal.

From observations on 4 satellites, 4 lengths to the satellites are obtained, and from them, arc

section, the coordinates of the antenna X Y Z and the correction of the clock U in the receiver

can be calculated. In order to achieve greater accuracy and precision, satellite measurements

are processed with the Bernise program package. The method of determining the coordinates

of the antennas is very precise, including the calculation of the lengths between multiple

antennas.

Today, it is the most precise method of measuring long distances.

GNSS the receiver has its own electronic clock.

Fig 4: Reference station

Page 4 of 14

327

Solarić, N., Solarić, M., Barković, Đ, Zrinjski, M., Bogdanovski, Z., Dimevski, S., & Postalovski, A. (2024). On the Method of Analysis for Earthquake

Forecasting. European Journal of Applied Sciences, Vol - 12(3). 324-337.

URL: http://dx.doi.org/10.14738/aivp.123.17043

Fig 5: Main GPS observation stations

Fig.6: By measuring at least 4 satellites, the coordinates of the XYZ position and the clock

correction in the receiver are determined.

Increase in Accuracy

1955. ± 100 m (triangulation Finland)

1965. ± 10 m - the first global network

1975. ± 1 m - by improving laser measurements

1985. ± 0.1 m - from the modernized TRANSIT system USA).

1995. ± 0.01 m - IGS network (Intelligence Gathering Satellite)

from GPS measurements

2022. approximately slightly weaker than ± 1 mm

So that surveyors could measure lengths with only one GPS and that they would be

determined, and the compression of the Earth's crust usually set up GNSS permanent

reference stations. Such a network of reference stations in Croatia is called CROPOS, and in

Serbia ARGOS. So that surveyors could measure lengths with only one GPS and that they

would be determined, and the compression of the Earth's crust usually set up GNSS

Page 5 of 14

Services for Science and Education – United Kingdom 328

European Journal of Applied Sciences (EJAS) Vol. 12, Issue 3, June-2024

permanent reference stations. Such a network of reference stations in Croatia is called

CROPOS fig.7., and in Serbia ARGOS. GNSS reference stations in Croatia in the CROPOS

network (marked in black as dots) fig.7. In neighbouring countries, GNSS reference stations

whose measurement data are exchanged with Croatia are marked with various colours.

EARTHQUAKE NEAR KRALJEVO ON NOVEMBER 3. 2010.

Analysis of length changes before and after the magnitude 5.4 earthquake at a depth of 10 km

near Kraljevo in 2010. In the Geodetic Service magazine no. 114 of Bosnia and announced that

the work was published. Then through them we got that work and what are the measured

lengths between GNSS points from 24-hour measurements for each day near the epicentre of

the earthquake.

Fig.7: Netz CROPOS

Fig.8: Reference stations

Page 6 of 14

329

Solarić, N., Solarić, M., Barković, Đ, Zrinjski, M., Bogdanovski, Z., Dimevski, S., & Postalovski, A. (2024). On the Method of Analysis for Earthquake

Forecasting. European Journal of Applied Sciences, Vol - 12(3). 324-337.

URL: http://dx.doi.org/10.14738/aivp.123.17043

They did not observe significant changes in geodetic coordinates for geodetic purposes in

ARGOS's network of reference stations near the epicentre of the earthquake fig. 8.

They chose the 4 closest reference stations near the epicentre of the earthquake and

calculated we have in EXCEL daily length changes for 6 days before the earthquake and 5 days

after the earthquake and showed them graphically as they changed over time.

We calculated the daily length changes in Excel and presented them graphically in time, fig.9.

Fig. 9: Daily length changes, 10.01.2010. almost all lengths were shortened, and in 2 days

there was an earthquake in Kraljevo.

They chose the 4 closest reference stations near the epicentre of the earthquake, and we are

calculated in EXCEL the daily length changes for 6 days before the earthquake and 5 days after

the earthquake and showed them graphically fig. 9. as they changed over time. We calculated

the daily lengths and displayed them on the graph.

We saw that day lengths shortened on 1/11/ 2010, fig.9. especially the length which were

closer to the future epicentre of the earthquake. Based on that, you can approximately

estimate where the future epicentre of the earthquake will probably be, and according to the

size of the compression, the intensity of the future earthquake can also be approximately

estimated.

Then we analysed the daily changes in longitude in Croatia during the earthquake in Drežnica

in 2013. Magnitude 4.6 according to Richter. We chose 4 CROPOS reference stations near the

epicentre of the earthquake fig. 10, in order to analysed daily length changes.

Page 8 of 14

331

Solarić, N., Solarić, M., Barković, Đ, Zrinjski, M., Bogdanovski, Z., Dimevski, S., & Postalovski, A. (2024). On the Method of Analysis for Earthquake

Forecasting. European Journal of Applied Sciences, Vol - 12(3). 324-337.

URL: http://dx.doi.org/10.14738/aivp.123.17043

after the earthquake in Skopje, 19 days before the earthquake and 12 days after the

earthquake fig.12.

After that, we analysed the daily length changes during the 2016 Skopje earthquake [3] of

magnitude 5.2 on the Richter scale. The analysis of daily changes in length during an

earthquake was made with the MAKPOS system. We selected 3 reference stations near the

epicentre and one in Skopje. After that, we calculated the daily length changes before and

after the earthquake in Skopje, 19 days before the earthquake and 12 days after the

earthquake. The compression of the terrain started on 28.07.2013. and the earthquake 3 days

later. The analysis of the daily changes in length during the earthquake using the MAKPOS

system. We chose 3 reference stations near the epicentre and one in Skopje. After that we

calculated the daily length changes before and after the earthquake in Skopje, 19 days before

the earthquake and 12 days after the earthquake. After that, we analysed the daily length

changes during the 2016 Skopje earthquake of magnitude 5.2 on the Richter scale, at a depth

of 4 km. The analysis of the daily changes in length during the earthquake was made using the

MAKPOS system. We chose 3 reference stations near the epicentre and one in Skopje. After

that we calculated the daily length changes before and after the earthquake in Skopje, 19 days

before the earthquake and 12 days after the earthquake. After that, we calculated sex daily

length changes before and after the earthquake in Skopje, 19 days before earthquake and 12

days after the earthquake. The until a small compression occurred on August 24, 2016. and in

2 days until a small earthquake.

Fig.12: MAKPOS near Skopje.

After that, we analysed the daily length changes during the 2016 Skopje earthquake of

magnitude 5.2 on the Richter scale, at a depth of 4 km. The analysis of the daily changes in

lengths during the earthquake were made using the MAKPOS system. We chose 3 reference

stations near the epicentre and one in Skopje. After that we calculated the daily length

Page 10 of 14

333

Solarić, N., Solarić, M., Barković, Đ, Zrinjski, M., Bogdanovski, Z., Dimevski, S., & Postalovski, A. (2024). On the Method of Analysis for Earthquake

Forecasting. European Journal of Applied Sciences, Vol - 12(3). 324-337.

URL: http://dx.doi.org/10.14738/aivp.123.17043

Fig. 15: Earthquake analysis in Zagreb and the surroundings we did using 3 quadrilaterals with

diagonals and one triangle with central point.

Fig 16: Earthquake in Zagreb

Page 11 of 14

Services for Science and Education – United Kingdom 334

European Journal of Applied Sciences (EJAS) Vol. 12, Issue 3, June-2024

From the graph, we can see that after greater compressions of the terrain, there were

earthquakes for 2 days or 3 days fig.16. Based on this result of the analysis, the Crisis

Commission, with a short consultation with seismologists, can very carefully announce that an

earthquake could occur in the next few days and that people should beware of the collapse of

buildings. Most seismologists think that it is impossible to predict the arrival of an

earthquake. At the Department of Geophysics in Zagreb, several papers were published which

at that time established that earthquakes cannot be predicted (Prof.Ph.D. Snježana Markušić,).

Today with satellites it is possible to forecast an earthquake.

In Zagreb, we examined the daily changes in longitude in the blue quadrangle and graphically

presented how they changed over time. Before the main earthquake, there was a minor

compression on 03/12/2020. and a minor earthquake after 2 days. The main compression

was on 03/20/2020. and after 2 days main earthquake.

We analysed 4 major earthquakes.

From the graph, we can see that after greater compressions of the terrain, there were

earthquakes for 2 days or 3 days. Based on this result of the analysis, the Crisis Commission,

with a short consultation with seismologists, can very carefully announce that an earthquake

could occur in the next few days and that people should beware of the collapse of buildings.

Most seismologists think that it is impossible to predict the arrival of an earthquake. At the

Department of Geophysics in Zagreb, several papers were published which at that time

established that earthquakes cannot be predicted (Prof. Ph. D Snježana Markušić.). Today with

satellites it is possible to predicted earthquake ahead.

After that, we analysed the daily length changes during the 2016 Skopje earthquake of

magnitude 5.2 on the Richter scale. The analysis of the daily changes in length during the

earthquake was made using the MAKPOS system. We chose 3 reference stations near the

epicentre and one in Skopje. After that we calculated the daily length changes before and after

the earthquake in Skopje, 19 days before the earthquake and 12 days after the earthquake.

Table 3: Earthquakes that we analysed using our method.

Page 13 of 14

Services for Science and Education – United Kingdom 336

European Journal of Applied Sciences (EJAS) Vol. 12, Issue 3, June-2024

The prosecution, on the other hand, claimed that the seismologists made their assessment

without a deeper analysis. They didn't have any measuring method back then to predict an

earthquake. The unsubstantiated information from the experts led the victims to stay in their

homes, and if they had only mentioned the possibility of a stronger earthquake, probably

many people would have been more careful and survived the disaster, had there not been 300

victims of the earthquake.

Members of the Crisis Commission were tried for manslaughter, destruction of buildings and

causing serious injuries because a week before the earthquake, hey made a statement that

there was no danger of a major earthquake in L'Aquila, and they eliminated the possibility of a

strong earthquake.

A major earthquake occurred in L’Aquila in 2009 with magnitude of 6.3 on the Richter scale.

300 people died. The court was initiated against the members of the Crisis Commission,

because they gave false information that there would be no major earthquake. At the next

session of the court, with a long session, they were still released. If they had made a statement

that there probably wouldn't be a big earthquake, they wouldn't have been judged, because

people would still have been careful and there wouldn’t have been so many 300 dead people.

In all cases of stronger earthquakes that we analysed, two to three days after stronger

compression of the Earth's crust, a larger earthquake occurred. After minor compressions,

minor.

Earthquakes occurred several days later.

If an earthquake like the one in 1880 were to occur in Zagreb today, 1⁄4 of the city would be

razed to the ground, and 3,000 inhabitants would die (according to the internet).

If an earthquake of the same intensity as in Petrinja had occurred today in Zagreb, 1⁄4 of the

city would have been razed to the ground, and 3,000 inhabitants would have died (according

to the internet).

They would suggest that the director of the State Geodetic Administration, which has

expensive equipment, Ph.D. Marijan Marjanović, the dean of the Faculty of Geodesy, and the

director of the Geophysical Department and the Crisis Staff and agree on how to finance it.

Thanks: We are very grateful to Professor Ph. D Eugen Prelogović for his advice. We hope that

during the next major earthquake in Zagreb, if this method is applied, there will be fewer dead

and injured citizens. Zagreb, not like in 1880 and in other poor areas of Croatia and the world

on compression Faults.

We would like to thank all our colleagues for their help.

We would also like to thank Antica Roka Solarić, and architect Sanja Veršić, who encouraged

us to work in this area, even though we did not have this project financed.

Page 14 of 14

337

Solarić, N., Solarić, M., Barković, Đ, Zrinjski, M., Bogdanovski, Z., Dimevski, S., & Postalovski, A. (2024). On the Method of Analysis for Earthquake

Forecasting. European Journal of Applied Sciences, Vol - 12(3). 324-337.

URL: http://dx.doi.org/10.14738/aivp.123.17043

Some colleagues told me why I was getting involved in seismic. We have seen today that this

method is the pure state-of-the-art geodetic method of measuring great length. Today, various

branches of science are intertwined. Prof. Ph.D. Nikola Čubranić Some colleagues told me why

I was interfering in seismic. We have seen today that this method is the pure most modern

geodetic method of measuring a large length.

Some colleagues asked me how I came up with the idea of prediction earthquakes? Prof. Ph.D.

Nikola Neihardt (Faculty of Forestry) announced in the 1960s that surveyors had discovered

that are also Earth's tides crusts. That's why I tried to look at how the Earth's crust behaves

before an earthquake.

References

Solaric N., Solaric M. (2012): Prijedlog da se u Zagrebu i okolici uz CROPOS-ove stanice postavi nekoliko GPS

(GNSS) permanentnih stanica za geodinamiku i moguću najavu većeg zemljotresa u slijedećem periodu vremena

(Proposal for Zagreb and Surroundings a few GNSS permanent stations for geodynamics and possibility the

announcement of larger earthquake in the future period), Geodetski list, Vol. 66 (92, 149-164(Croatia).

http://hrcak.srce.hr/95827.

Solaric N., Solaric M., Pejakovic M. (2017): Dva dana prije potresa u Drežnici 2013. godine došlo je do kompresije

terena (Two days before the Earthquake in Dreznica 2013 there has been compression of terrain), Geodetski list,

Vol. 71 (94), No. 3, 203-214. (Croatia) https://hrcak.srce.hr/index.php?show=clanak&id

Solaric N., Solaric M., Bogdanovski Z., Dimeski S. (2018): Three days before the Earthquake in Skopje there was a

compression of the Earth's crust, Geodetski list, Vol. 72 (95), No. 1, 15-35 (2018), https://hrcak.srce.hr/200222.

Solaric N., Solaric M. (2020): Proposal for Zagreb and Surroundings a few GNSS permanent stations for

geodynamics and possibility the announcement of larger earthquake in the future period), Geodetski list, Vol. 66

(92, 149164 (Croatia). http://hrcak.srce.hr/95827.

We have a reviewed chapter of the book published in Intechopen.com.

The Possibility of Earthquake Forecasting, A Few Days before the Earthquake using GNSS Satellites, WRITTEN

BY Nikola Solarić and Miljenko Solarić the Possibility of Earthquake Forecasting, a Few Days before the

Earthquake Using GNSS Satellites, December 2022

In book: Earthquakes - Recent Advances, New Perspectives and Applications [Working Title] OI:

10.5772/intechopen.10884 Reviver Dr Walter Salazar write „The Chapter written by Solaric brothers present a

fantastic application of GPS satellites for, analysing the distance changes amongst different Earth stations before

and after an occurrence”. Hower, I would like to write soma comments that might improve the quality of the

manuscript.