Earthquake Map Plot: 2001-2022

# Load necessary libraries
pacman::p_load(pacman, readr, ggplot2, maps, mapdata)

# Load the CSV file 
earthquake_1995_2023 <- read_csv("earthquake_data.csv")

## Rows: 782 Columns: 19
## ── Column specification ────────────────────────────────────────────────────────
## Delimiter: ","
## chr  (8): title, date_time, alert, net, magType, location, continent, country
## dbl (11): magnitude, cdi, mmi, tsunami, sig, nst, dmin, gap, depth, latitude...
## 
## ℹ Use `spec()` to retrieve the full column specification for this data.
## ℹ Specify the column types or set `show_col_types = FALSE` to quiet this message.

# Basic World Map using ggplot2
world_map <- map_data("world")

# Create a plot
ggplot() +
  # Draw the world map with green land
  geom_polygon(data = world_map, aes(x = long, y = lat, group = group), 
               fill = "#66cc33", color = "#666666") +
  # Plot earthquake data points
  geom_point(data = earthquake_1995_2023, 
             aes(x = longitude, y = latitude, size = magnitude, color = depth), 
             alpha = 0.6) +
  # Customise size scale
  scale_size_continuous(name = "Magnitude", range = c(1, 5)) +
  # Customise colour scale for depth
  scale_color_gradient(name = "Depth (km)", low = "#ffff99", high = "#cc0033") +
  # Add labels and title
  labs(title = "Earthquakes from 2001 to 2022",
       x = "Longitude", 
       y = "Latitude") +
  # Set theme
  theme() +
  # Map appearance
  theme(panel.background = element_rect(fill = "#99ccff"),  # Blue water
        panel.grid.major = element_blank(),
        panel.grid.minor = element_blank(),
        plot.background = element_rect(fill = "#cccccc"))   # grey plot background