It’s been a busy week for seismometers. This morning, at 12:49 a.m. Michigan time, GRCC’s seismic station (GRMI) recorded a magnitude 8.1 earthquake (see red arrow in image below) off the Pacific Coast of Mexico. See the United States Geological Survey’s shake map below for location of the main shock and shaking intensity. This was the largest earthquake ever recorded on our station. Preliminary reports are that there are casualties and building collapses in communities closer to the earthquake. Mexico City appears to have sustained little damage or injuries thanks to strong building codes (since the devastating 1985 earthquake) and an early warning system that gave residents about 40 seconds to move to a place of safety. See the New York Times article for updates on the impact and the USGS website for additional information about the earthquake and aftershocks.