"Last week’s powerful earthquake in Chile may have shifted the Earth’s axis and changed the length of a day, according to NASA researchers. The magnitude 8.8 quake of February 27 was powerful enough to alter the position of the planet’s figure axis, an imaginary line around which the mass of the planet rotates, by about 3 inches. That adds up to an Earth day that lasts about 1.26 microseconds less than it did before the earthquake. We’ll talk about how geological processes can effect the planet’s rotation, and how researchers model planetary movements."
Incidentally, this also mentions Charles Darwin & the Beagle’s assistance and observations of a Chilean earthquake in the same spot as the recent one. It mentions how that quake shaped Darwin’s geologic interests that helped shape his theory of evolution. Great stuff. Also mentions FitzRoy, the captain of the Beagle. The same story is fictionalized (but still historical in inspiration) in "This Thing of Darkness" which I highly, highly recommend.
From http://www.sciencefriday.com/program/archives/201003051