Two 4+ earthquakes overnight on Hawaiʻi Island, likely part of “seismic swarm”

Two 4+ magnitude earthquakes that occurred within seconds of each other overnight on Hawaiʻi Island, were likely part of the seismic swarm under the Pāhala area, which has been going on since 2019, scientists say.

In an information statement, the HVO notes that the first 4.3 earthquake occurred on Friday, April 15, at 1:58 a.m., about five miles NE of Pāhala at a depth of 21 miles. Then, eight seconds later, a magnitude-4.6 earthquake occurred slightly to the SE of the first one, at a depth of 20 miles.

Both occurred in the southwest rift zone of the Kīlauea volcano.

US Geological Survey’s Hawaiian Volcano Observatory geophysicist, Jefferson Chang said these earthquakes had no apparent effect on Kīlauea or Mauna Loa volcanoes.

“Earthquakes in this region have been observed at least as far back as the 1960s. We see no detectable changes in activity at the summits or along the rift zones of Mauna Loa or Kīlauea as a result of these earthquakes,” Chang said.

According to the USGS “Did you feel it?” service more than 400 felt reports were received within the first hour of the earthquakes from people who felt the tremors.  The second, larger earthquake, had “felt reports” logged in both Wailuku and Kula on Maui, as well as Honolulu on Oʻahu.

The Pacific Tsunami Warning Center in Honolulu quickly issued a statement following the events, saying that no tsunami was expected, and no action was required.