Which seismic zone triggered the 2010 Indiana earthquake?
2010 Indiana earthquake The 2010 Indiana earthquake registered 3.8 on the moment magnitude scale and struck near Greentown and Kokomo on December 30, 2010 at 12:55:21 UTC at a depth of 3 mi. The quake occurred approximately 50 miles north of Indiana's capital, Indianapolis. It joins only three other earthquakes that have affected the northern Indiana area since 1999. The “extremely rare and unprecedented” earthquake had the largest magnitude of a northern Indiana earthquake in 175 years. Despite being considered a rare occurrence, the affected region of northern Indiana lies near many fault lines including the Wabash Valley Seismic Zone and the New Madrid Seismic Zone. Both zones are hotspots for tectonic activity, with the Wabash Valley Fault Zone reaching earthquake depths up to 18 km (11.4 mi.) deep. It was incorrectly recorded by nearby stations as a 4.2 magnitude before being downgraded to 3.8. No significant damage was reported from the incident, but the quake was felt by thousands, spanning across multiple cities and states. Towns as far away as Kalamazoo, Michigan and states as far as Wisconsin and Kentucky reported the earthquake.
2001 Nisqually earthquake The 2001 Nisqually earthquake (also commonly referred to as "The Ash Wednesday earthquake") occurred at on February 28. The intraslab earthquake had a moment magnitude of 6.8 and a maximum Mercalli intensity of VIII ("Severe"). The epicenter was in the southern Puget Sound, northeast of Olympia, but the shock was felt in Oregon, Canada, eastern Washington, and Idaho. This was one of several large earthquakes that occurred in the Puget sound region in the prior 52 years and caused property damage valued at between one and four billion dollars. One person died of a heart attack and several hundred were injured.