Three more aftershocks have rocked New Zealand following a 7.8-magnitude earthquake off South Island a few days earlier. The quakes of 4.5, 4.9 and 5.1 magnitude were felt Saturday morning in the Fiorldland district, bringing the number of aftershocks since Wednesday's quake to 16. That quake, the biggest recorded in the world this year, caused no injuries and only minor damage. Scientists said the quake occurred in soft rocks'' between two tectonic plates, muffling its power.