PASSIVE/CONSERVATIVE BOUNDARY
This occurs when two plates are forced to slide past one another so that crust is neither created nor destroyed. As the two sections of the crust slide or grind past one another, pressure builds up in the rocks which may be released suddenly and last only a few seconds, resulting in the jerking forward of rocks on either side of the boundary line and thus violent earthquakes occur.
Volcanoes are NOT found at passive plate boundaries because there is no subduction and therefore no magma or volcanic eruption.