Earthquake Epicenters in North Carolina and Portions of Adjacent States (1698-1997)
This is a map of earthquake epicenters recorded in North Carolina and portions of adjacent states between 1698 and 1997. Epicenters are shown only for labeled states. Major geologic provinces and known major faults exposed at the surface are shown for North Carolina. Faults identified to date in North Carolina are ancient and inactive. The lack of correspondence between the locations of earthquake epicenters and these faults indicates they are not responsible for earthquakes in North Carolina within historical times. The faults beneath the surface that generate earthquakes have yet to be positively identified.
Earthquake data before 1886 are sparse. Seismic instruments were installed in the region in the late 1920's. Prior to that time earthquake data are based on historical records. The distribution of seismograph stations did not allow for location of earthquakes with magnitudes <4 until 1962-1963. Micro-earthquake networks began operating in the region in the mid-1970's.
Geology from North Carolina Geological Survey, 1985, Geologic Map of North Carolina (scale 1:500,000). Earthquake data from 1698-1992 are from Virginia Polytechnical and State University. Data from 1993-1997 are from the U. S. Geological Survey National Earthquake Information Center (http://wwwneic.cr.usgs.gov/).
The map and text above are modified from Geologic Note 7: Map of Earthquake Epicenters in North Carolina and Portions of Adjacent States (1698-1997). To get a copy of Geological Note 7, contact our Sales Office.