Magnitude 6.2

Well? That was the strongest shake we have had in a while. Magnitude 6.2 well offshore of the south end of the island.

The whole house rattled for a while, then a few sharp bangs, then it rumbled on for a while longer. Nothing knocked off shelves, just a steady rattle of plates and photos on the wall. The 3D printer took no notice, happily plotting along.

The cats did take notice, Electra disappearing under the bed, not to re-appear for a while. Ras was all perky-eared and vigilant.

For this quake I guessed not only the distance correctly, but the magnitude to within 0.3, (guessed 6.5, USGS revised 6.2). We have plenty of experience with big island shakes at this point. I felt both the S and P waves arrive, that gave me distance. What surprised me is the depth, 21 miles down, that is below the crust, into the mantle.

Magnitude 6.1 Down South
USGS plot of a magnitude 6.1 earthquake off the south end of the island with aftershocks, Oct. 10, 2021

Author: Andrew

An electrical engineer, amateur astronomer, and diver, living and working on the island of Hawaiʻi.

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