In the U.S.Pacific Northwest, investigators have observed many silent earthquakes along the enormous Cascadia fault zone between the North American plate and the subducting Juan de Fuca plate.

• 在美国西北环太平洋地区，研究人员曾监测到有许多无声地震发生在卡斯卡迪亚断层带内，也就是位在北美板块和正在隐没的德富卡板块之间。