Watch the explosion in the video player above.An "experimental explosion" triggered by the Navy about 100 miles off the Florida coast registered as a 3.9 magnitude earthquake on Friday. The blast is known as a "shock trial," an explosion meant to test a ship's ability to withstand nearby detonations. The Navy was testing its new aircraft carrier — the USS Gerald R. Ford.These types detonations have been purposely triggered for decades after the Navy discovered nearby explosions could knock out key systems on its vessels, even when they don't cause physical damage.This marks the first time the Navy has conducted shock trials since it tested the USS Theodore Roosevelt aircraft carrier in 1987.Military officials say the tests are in compliance with environmental requirements that consider the migration patterns of marine life.