Any motion against the tectonic ( related
with structure of earth's surface) plate
against the other increases strain hence
store potential energy. The contineous
movements keep increassing the strain to
breaking point. Once the breaking point is
crossed, this energy is released as a combi-
nation of radiated seismic waves, frictional
heating of the fault surface and cracking
of the rock, thus causing a earthquake.
Hence the earthquake is result of energy
in Earth's crust ( hard outer layer) that
create seismic waves. ( connected with or
caused by earthquake).