=Paper=
{{Paper
|id=Vol-2030/HAICTA_2017_paper32
|storemode=property
|title=A Statistical Investigation of Earthquakes in Greece and the Effect of the Lunar Triggering
|pdfUrl=https://ceur-ws.org/Vol-2030/HAICTA_2017_paper32.pdf
|volume=Vol-2030
|authors=Stavros Fatouros,Evangellia Kossieri,Miltiadis Chalikias,Perikles Papadopoulos
|dblpUrl=https://dblp.org/rec/conf/haicta/FatourosKCP17
}}
==A Statistical Investigation of Earthquakes in Greece and the Effect of the Lunar Triggering==
https://ceur-ws.org/Vol-2030/HAICTA_2017_paper32.pdf
A Statistical Investigation of Earthquakes in Greece and
the Effect of the Lunar Triggering
S. Fatouros1, E. Kossieri2, M. Chalikias3, P. Papadopoulos4
1
Department of Computer Systems Engineering, Piraeus University of Applied Sciences,
email: fatouros@puas.gr
2
Department of Accounting and Finance, Piraeus University of Applied Sciences, email:
kossieri@puas.gr
3
Department of Business and Administration, Piraeus University of Applied Sciences, email:
mchalikias@hotmail.com
4
Department of Electronics Engineering, Piraeus University of Applied Sciences, email:
ppapadop@puas.gr
Abstract. The aim of this paper is to investigate the influence of the lunar
period in Greek earthquakes. All earthquakes of magnitude >4 within the
decade 2000-2009 have been classified according to their time distance from
the full moon and studied with statistical methods.
Keywords: Greek Earthquakes, Lunar Triggering, independent Samples T-
Test.
1 Introduction
Lunar gravity force as a triggering factor of earthquakes is an hypothesis of
discussion statistically examined in the seismological society since the end of the
19th century (Knott 1896; Schuster, 1897), in many different geographical regions as
in (Allen, 1936; Lin et.al 2003). The geological form is dominated by alpine
(marbles, schists, limestones and sandstones) and post-alpine rocks (Neogene and
loose Quaternary formations) (Diakakis et al., 2016).
Greece is located at the front of the collision between two tectonic plates, the
Eurasian and the African, the front part of which is sinking under the former. As a
result although Greece covers 0.09% of the global area it accounts for the 2% of the
global seismicity (Bath, 1983) and it is by far the most seismic country in Europe
(Chalikias, 2012).
In the present paper we investigate whether there exists a statistic significant
correlation between the seismic phenomena in Greece and their distribution in the
lunar time. Data of earthquakes in Greece were used and the correlation was proved
by the usage of statistical Tests.
2 Research Methodology
The data of this researched have been obtained from the detailed catalogue of
earthquakes in Greece and adjacent areas in (Makropoulos et al, 2012). Due to the
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hundreds of the earthquakes that take place every year we constrained our sample on
the ones of magnitude 4 or higher that took place within the ten year period 2000-
2009.
We classified the sample according to the daily distance from the date and
accurate time of the nearest full moon. We defined as 0-day the period consisted of
the 12 hours prior and 12 hours after the earthquake. For the processing of the data
we have used the IBM SPSS Statistics Software Package. With Kolmogorov
Smirnov Test the normality of the data were examined and one sample T-Test were
used to demonstrate the correlation of earthquakes and the effect of Lunar
Triggering.
3 Statistical Analysis
From earthquake data collected from the period 2000-2009, we observe that 59%
of the earthquakes occur during the period beginning 6 days before and ending 6
days after the day of the full moon (Table 1), while a large majority, 81.3% of the
earthquakes occur during the period beginning10 days before and ending 10 days
after the day of the full moon (Table 2).
Table 1. Time distance between earthquakes and the full moon
Cumulative
Time Distance from Count of Percent of
percent of
Daylight Saving Day earthquakes earthquakes
earthquakes
(counted in days)
7 and more 53 39,6 40,2
Up to 6 79 59,0 100,0
Total 132 98,5
Missing 2 1,5
Total 134 100,0
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Table 2. Time distance between earthquakes and the full moon
Cumulative
Time Distance from Count of Percent of
percent of
Daylight Saving Day earthquakes earthquakes
earthquakes
(counted in days)
11 and more 23 17,2 17,4
Up to 10 days 109 81,3 100,0
Total 132 98,5
Missing 2 1,5
Total 134 100,0
The normality test for the time distance between earthquakes and the full moon
was then performed. The test revealed that the time distance variable follows the
normal distribution with mean time distance -0.34 days and standard deviation of
7.34 days.
The t-test, performed for the time distance of 6 day had the results shown in Table
3.
Table 3. t-Test
Test Value = 6
t Df Sig. (2-tailed) Mean Difference 95% Confidence Interval of the
Difference
Lower Upper
V16 ,147 131 ,883 ,05303 -,6594 ,7654
From the results of this statistical analysis we cannot exclude the research
hypothesis that the average time distance between earthquakes and the full moon is 6
days.
4 Conclusions
Although there is not a satisfactory model on the effect of lunar triggering the
discussion has come recently to the surface due to results that relate statistically
earthquakes of high magnitude with the lunar phases (Ide et.al. 2016). It is easy to
conclude that except the wavelet analysis (Haigh et.al., 2002) statistical methods can
be used in order to examine the connection between the earthquakes and the effect of
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the Lunar Triggering. The present work focuses on the large-scale earthquakes that
took place within a decade in Greek territories. The result proves a connection
between the time that earthquakes take place and the effect of the Lunar Triggering
(more earthquakes take place near Lunar Triggering days. Furthermore it is of
interest the distribution of the intense of the earthquakes to be examined.
References
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