This data set is a reduced version of the full data set in Scott (1992). It contains the first three variables.
data(earthquake)
A matrix with 3 columns and 510 rows. Each row corresponds to the measurements of an earthquake beneath the Mt St Helens volcano. The first column is the longitude (in degrees, where a negative number indicates west of the International Date Line), the second column is the latitude (in degrees, where a positive number indicates north of the Equator) and the third column is the depth (in km, where a negative number indicates below the Earth's surface).