EARTHQUAKES AT GRONINGEN

Earthquakes at the province of Groningen are induced by the mining of natural gas since the sixties. The KNMI has recorded and collected the data of the quakes. Inspired by Maarten Lambrechts I loaded the data into a template at Flourish gives the following time chart:

Next I loaded the data into R studio to detail the analysis.

Aardbevingen in R

b<-read.csv("beving.csv")
> str(b)
'data.frame':   1478 obs. of  11 variables:
 $ YYMMDD  : int  19861226 19871214 19891201 19910215 19910425 19910808 19911205 19920523 19920524 19920611 ...
 $ TIME    : num  74751 204948 200917 21117 102632 ...
 $ LOCATION: Factor w/ 160 levels "Alkmaar","Amen",..: 8 53 64 33 32 8 78 43 8 103 ...
 $ LAT     : num  53 52.9 52.5 52.8 53 ...
 $ LON     : num  6.55 6.55 4.97 6.91 6.58 ...
 $ DEPTH   : num  1 1.5 1.2 3 3 3 3 3 3 1.5 ...
 $ MAG     : num  2.8 2.5 2.7 2.2 2.6 2.7 2.4 2.6 1.6 2.7 ...
 $ jaar    : num  1986 1987 1989 1991 1991 ...
 $ maand   : num  12 12 12 2 4 8 12 5 5 6 ...
 $ dag     : int  26 14 1 15 25 8 5 23 24 11 ...
 $ DATE    : Factor w/ 1209 levels "01/01/2003","01/01/2009",..: 1029 545 33 549 967 303 183 880 931 417 ...

summary(b$MAG)

Magnitude
   Min. 1st Qu.  Median    Mean 3rd Qu.    Max.    NA's 
  0.000   0.800   1.100   1.204   1.500   3.600      32 

plot(density(b$MAG,na.rm=TRUE))
abline(v=mean(b$MAG,na.rm=TRUE, color="red"))

summary(b$DEPTH)

Depth

   Min. 1st Qu.  Median    Mean 3rd Qu.    Max.    NA's 
  1.000   3.000   3.000   2.963   3.000   3.500      14 

plot(density(b$DEPTH,na.rm=TRUE))
abline(v=mean(b$DEPTH,na.rm=TRUE, color="red"))

j<-table(b$jaar)
j=as.data.frame(j)
j

4    1987    1
5    1989    1
6    1991    4
7    1992    6
8    1993   16
9    1994   29
10   1995   18
11   1996   41
12   1997   42
13   1998   23
14   1999   31
15   2000   26
16   2001   23
17   2002   25
18   2003   57
19   2004   31
20   2005   36
21   2006   56
22   2007   32
23   2008   49
24   2009   91
25   2010   41
26   2011   93
27   2012  102
28   2013  130
29   2014   85
30   2015  122
31   2016  118
32   2017  127
33   2018   11

str(j)
'data.frame':   33 obs. of  2 variables:
 $ Var1: Factor w/ 33 levels "7.021","53.224",..: 1 2 3 4 5 6 7 8 9 10 ...
 $ Freq: int  9 1 1 1 1 4 6 16 29 18 ...
qplot(j$Var1,j$Freq)