The U.S Geological Survey has already issued an informative poster on the Chile earthquake, which can be downloaded here.
Here is the first part of the poster:
subduction zone (hatched line), where the Nazca plate on the left dives beneath the South American plate on the east. The epicenter of yesterday's quake (star) is not far from the largest earthquake ever measured, from 1960. The colors denote the depth of the hypocenters.
We'll look at other parts of the poster in upcoming posts.