Northwest Louisiana recently experienced a 4.9 magnitude earthquake, with residents reporting beds shaking and walls vibrating.
This quake was much more intense than what’s typical in Louisiana, with earthquakes measuring 4.0 or higher in magnitude only occurring once every six years.
Earthquakes with a magnitude from 2.0 to 2.9 are more common, occurring about five times a year on average.
Fault lines, tectonic zones in Louisiana and how they lead to earthquakes
Louisiana is located within the Gulf Coast Basin geological tectonic zone. This area is considered to have low to no seismicity, which refers to the occurrence or frequency of earthquakes.
While Louisiana has low seismic activity and does not rest on a tectonic plate boundary, the state does have shallow growth faults in the northwestern and southern regions, according to Emergency Response Guide.
Growth faults allow for blocks of earth to move over long periods as sediments are deposited on or above the fault, eventually causing a displacement of the land.
This means that seismic activity is more of a gradual creep along faults versus sudden movement along a fault that results in an earthquake, says Emergency Response Guide.
In Louisiana, these growth faults exist within areas in proximity to Caddo Lake, Arcadia, the Toledo Bend Reservoir, Baton Rouge and Lake Pontchartrain, according to a map from Data Basin.
Presley Bo Tyler is a reporter for the Louisiana Deep South Connect Team for USA Today. Find her on X @PresleyTyler02 and email at PTyler@Gannett.com
This article originally appeared on Shreveport Times: Why does Louisiana have earthquakes? Faults in the state cause tremors
