M6.4 North Slope earthquake evolving content

Recordings from pump station instruments

Lea Gardine made this figure showing ground motion (cm/sec) from the magnitude 6.4 Kaktovik earthquake as recorded by our seismic instruments at pump stations along the Trans-Alaska Pipeline.

Waveforms from selected TA stations

Kasey Aberhold (IRIS) created this figure showing the earthquake as recorded on a selection of Transportable Array seismic stations. The Transportable Array project has dramatically improved our ability to monitor seismicity in Northeast Alaska, as previously there were very few stations in the area. The nearest stations to the epicenter are at the bottom of the figure.

Ground Motion Visualization

30 minutes of ground motion data following the 6.4 earthquake. Included are two aftershocks - a 4.9 at 7:14 am AKDT and a 4.7 at 07:18 AKDT.

Map of the first 8 hours

The M6.4 mainshock plotted along with the first 8 hours of aftershocks. Seismic stations are grey triangles. The light orange line marks the ANWR boundary.

48 hours of reviewed Aftershocks - as of 8/14

Our system is automatically locating many aftershocks, and it will take a few days before our data analysts can review all of the smaller earthquakes and refine their locations. Larger aftershocks are reviewed by our duty seismologist right away. This map shows the first 48 hours of reviewed aftershocks following the Kaktovik M6.4 earthquake on Sunday. We'll update these maps are more aftershocks are reviewed. Also shown on this map are the beachball representations of fault motion from the M6.4 mainshock (left) and M6.0 aftershock (right).