Map showing epicenter of a magnitude 3. Associated Press graphic. I lived in California for a while where I taught kids about earthquakes at the Birch Aquarium at Scripps. Fault lines and tectonic plates were familiar terms to people out there, as were the feelings of the floor rumbling and bookshelves shaking. But here in Maine, those are not such common words or sensations.
Last week, however, there were three earthquakes back to back β and all of them happened offshore, underwater. The quakes all centered about 10 miles off the shores of York Harbor. The waters closer to shore are familiar to me from graduate school as a site we commonly used for SCUBA training. I wondered, however, what it would be like to be underwater during an earthquake. If people felt this quake as far south as Connecticut, then certainly there must have been impacts on the marine environment and the creatures that live there.
Earthquakes impact marine life in a variety of ways. These can include literally shaking sediment loose from the seafloor, making the water more cloudy. It can be just sediment in some cases but can also include breaking up seafloor habitat in others. For the mobile and more sensory creatures, the seismic waves can result in changes in pressure. This is something that many fish and marine mammals are very sensitive to and use for hearing and for navigation. The changes in pressure may temporarily scramble these senses.
The biggest impact of an earthquake underwater can be a tsunami. This is a giant wave that is generated by the upheaval of the seafloor. However, the size of the quakes in Maine were not strong enough to create a tsunami. The first quake, which occurred on Jan. The quakes that we have in Maine are predominantly in this lower range.
Instead, the earthquakes are caused by a buildup of pressure as the land mass moves on top of the North American Tectonic Plate.
