Magnitude 4.2 Earthquake Strikes South of Kaktovik on Eastern North Slope

A magnitude 4.2 earthquake rattled the eastern North Slope early Wednesday morning, with its epicenter recorded at coordinates 69.433°N, 143.562°W, placing it roughly 43 to 48 miles south of Kaktovik. The U.S. Geological Survey logged the event at approximately 15:59:58 UTC on March 11, 2026, which translated to 6:59 a.m. local Anchorage time. USGS assigned the quake event ID aka2026exwycc and the data was confirmed through manual revision using readings from 59 seismic stations.

The quake registered at a very shallow depth of 5.2 kilometers, or about 3.2 miles beneath the surface. Shallow earthquakes typically radiate energy more intensely at ground level than deeper events of comparable magnitude, though seismic monitoring data showed intensity reaching only moderate levels near the epicenter. Despite that classification, no felt reports were submitted to seismic monitoring networks as of the time of publication.

Conditions at the epicenter at the time of the quake included overcast skies, a temperature of -20.6°C (-5°F), humidity at 94 percent, and a light southwest wind. The remote stretch of tundra sits approximately 100 kilometers from the Canadian border.

The eastern North Slope carries a documented history of seismic activity. In August 2018, a magnitude 6.4 earthquake struck roughly 52 miles southwest of Kaktovik, a separate and far larger event that the Alaska Earthquake Center described as the most powerful ever recorded north of the Brooks Range. That 2018 sequence, which included a magnitude 6.0 aftershock, prompted seismologists to note that the eastern Brooks Range sits within a seismic zone spanning roughly 240 miles long and 120 miles wide, from the Beaufort Sea south to the Tintina fault. The Alaska Earthquake Center reported more than 4,400 earthquakes recorded in the area since 1970 prior to that 2018 event.

The March 11 magnitude 4.2 event is considerably smaller in scale. No damage reports or emergency declarations from North Slope Borough officials have been issued in connection with the quake. Anyone who felt shaking in Kaktovik or surrounding areas can submit a report directly to the USGS event page using event ID aka2026exwycc, which remains the authoritative record for this earthquake.