The quakes_1_per, quakes_10_per
and quakes_100_per are 3 modified versions of the earthquake dataset
obtained from Geology Department at University of Houston. These datasets
define the depth of epicenters of different earthquakes in different
locations.
Each of these 3 spatial datasets
consists of 3 attributes containing Longitude and Latitude of the
epicenter of earthquake and the Depth of the earthquake which is shallow
(1), intermediate (2) and deep (3).