2011 Virginia earthquake
The USGS found that the farthest landslide from the 2011 Virginia earthquake was from the epicenter. This is by far the greatest landslide distance recorded from any other earthquake of similar magnitude. Previous studies of worldwide earthquakes indicated that landslides occurred no farther than from the epicenter of a magnitude 5.8 earthquake. The study suggested that the added information about East Coast earthquakes may prompt a revision of equations that predict ground shaking. "What makes this new study so unique is that it provides direct observational evidence from the largest earthquake to occur in more than 100 years in the eastern U.S. Now that we know more about the power of East Coast earthquakes, equations that predict ground shaking might need to be revised."
1755 Cape Ann earthquake
Modern research has estimated that the quake was between 6.0 and 6.3 on the Richter scale, and the United States Geological Survey lists it as the largest earthquake in the history of Massachusetts. Scientists are unclear on the causes of this and other quakes in the northeastern United States. There are a number of old faults in the region, but none of them are known still to be active. It is possible that the Cape Ann earthquake may have been remotely triggered by a larger earthquake in Lisbon, Portugal, a few weeks prior, although there is not enough evidence to prove that they are linked.