Final answer:
Fault zones are areas around fault traces where tectonic plates move several centimeters per year. The width of these zones can vary and the provided texts do not define a specific measurement in yards.
Step-by-step explanation:
The fault zones are areas surrounding the fault trace, which is the surface representation of a fault in the earth's crust. Active fault zones exhibit movement of tectonic plates relative to one another at a rate of several centimeters per year. This movement is parallel to the fault and is similar to the spreading rates along rifts in the earth's crust. The description provided does not specifically state the defined width of a fault zone in yards on either side of the fault trace; such measurements can vary greatly depending on the context and geographic location. For instance, the San Andreas Fault has different slippage intervals and magnitudes of movement in various segments along its length.