Mapping Earthquake in Bohol using R

On my previous post a year ago (on mapping earthquake recorded for the Philippines), it can be seen that there were no earthquake (epicenter) recorded for the province of Bohol. But on the 15th of October there were more than 40 quakes recorded that hit the island from early in the morning till late midnight with magnitude ranging from 2.7 to 7.2.

Below is the map, created using R, of earthquakes that hit the province:

Negros Quake Animation in R

Taken from a previous post in other website, maps below show the locations of epicenters and sequence of earthquakes that struck Negros last February 6, 2012. The bottom image is the animation these maps using animation package in R. Data was taken from United State Geological Survey.

Earthquake Density in the Philippines (2011-2012)

Using the same data and package from my previous post, but minor tweak on the code, I produced the map below:

Mapping Global Earthquake using XML and Maptools

Everyday the US Geological Survey (USGS) publish earthquake data (http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/quakes_all.html) all over the globe. Using XML and maptool packages of R I downloaded and map USGS earthquake data using the following codes :

library(XML)
usgseq<-"http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/quakes_all.html"

weq1 = readHTMLTable(usgseq, header=T, which=1,stringsAsFactors=F)
weq2 = readHTMLTable(usgseq, header=T, which=2,stringsAsFactors=F)
weq3= readHTMLTable(usgseq, header=T, which=3,stringsAsFactors=F)
weq4 = readHTMLTable(usgseq, header=T, which=4,stringsAsFactors=F)
weq5 = readHTMLTable(usgseq, header=T, which=5,stringsAsFactors=F)
weq6 = readHTMLTable(usgseq, header=T, which=6,stringsAsFactors=F)
weq7 = readHTMLTable(usgseq, header=T, which=7,stringsAsFactors=F)
weq8 = readHTMLTable(usgseq, header=T, which=8,stringsAsFactors=F)

eq<-rbind(weq1,weq2,weq3,weq4,weq5,weq6,weq7,weq8)


weq<-eq[,c(2,4,5)]
x<-as.numeric(weq[,3])
y<-as.numeric(weq[,2])
z<-as.numeric(weq[,1])

library(maptools)
data(wrld_simpl)
plot(wrld_simpl, col="green4", border="white", axes=T)

plot(wrld_simpl, col="green4", border="white")
points(y~x, cex=(z^2)/12, col=ifelse(z>5,"red","blue"), pch=19)
text(0,101,"Global Earthquake Maps (May 15-23,2012)", cex=1.8)
text(-180,-95,"Data Source: USGS\nCreated by: ARSalvacion", adj=0, cex=0.5)

Mapping Philippines earthquake data from January 2011 to January 2012

Mapping Philippines earthquake data from January 2011 to January 2012 collected by PHIVOLCS using R ggplot package.

I tried to recreate the earthquake map of the Philippines created using maptool and R plot function using ggplot2.

Earthquake map using plot function

Earthquake map using ggplot function