Load a table of earthquakes around Japan as a pandas.Dataframe.
Data is from the NOAA NGDC database. This is the
@tut_quakes.ngdcdataset used in the GMT tutorials.
The data are downloaded to a cache directory (usually
~/.gmt/cache) the first time you invoke this function. Afterwards, it will load the data from the cache. So you’ll need an internet connection the first time around.
The data table. Columns are year, month, day, latitude, longitude, depth (in km), and magnitude of the earthquakes.