text: what does a good transmit of seismic waves have to do with an earthquake affecting a large region? oops i put hurricane  on my old question there i meant earthquake earth quake energy is seimic waves.    if the composite of the region is dense and solid these waves can travel further and effect a much larger area.  conversely, if the region is less dense and not solid, these waves will be absorbed and the range of the earth quake will be limited.  to test this, use a table, a large book, a glass of water and a box of cat litter.  set the box of cat litter on the next to the glass, and slam the book as hard as you can into the kitty litter while your partner watches the water.  now switch remove the cat litter and repeat with the book hitting the solid table.  you should see the the water was more disrupted in the second experiment than in the first.