No tsunami threat after two 4+ magnitude earthquakes off Hawaiʻi Island within an hour

By Wendy Osher

There is no tsunami threat to Hawaiʻi after a second 4+ magnitude earthquake reported off of Hawaiʻi Island within an hour of a previous quake in the region.

This latest earthquake was measured at a preliminary magnitude of 4.6, and was located at the Kama‘ehuakanaloa (previously known as Loihi) Seamount, south of the Big Island. The quake was reported at 6:28 p.m. on Tuesday, July 26, 2022.

The Pacific Tsunami Warning Center reports that there is no tsunami expected from either incident.

“This second quake is a relatively shallow earthquake that occured in the vicinity of the earthquake swarm that took place within Kamaʻehukanaloa from July 16 to 18 and may represent stress release related to this event.  There is no sign that this is related to renewed magmatic activity.  It is also unusual to have two moderate earthquakes occur so close in time and proximity, but there is no apparent relationship between the two events,” said HVO Scientist-in-Charge Ken Hon in an information statement.

An earlier 4.3 earthquake was reported at 5:46 p.m. on Tuesday, July 26, in the SW rift zone of the Kīlauea Volcano on Hawaiʻi Island, about 30 miles north of the second, unrelated quake.

The USGS Hawaiian Volcano Observatory reports that the first earthquake was part of the seismic swarm under the Pāhala area, which has been going on since 2019. Earthquakes in this region have been observed at least as far back as the 1960s, according to the HVO.

The HVO outlined the five previous most recent Magnitude 4 or greater earthquakes in Hawaiʻi:

• 2022 May 22—Magnitude 4.7—2 mi (3 km) NW of Hōlualoa, Island of Hawaiʻi
• 2022 April 15—Magnitude 4.6—6 mi (9 km) E of Pāhala, Island of Hawaiʻi
• 2022 April 15—Magnitude 4.3—5 mi (8 km) E of Pāhala, Island of Hawaiʻi
• 2022 March 20—Magnitude 4.5—13 mi (21 km) SSE of Waimea, Island of Hawaiʻi
• 2022 Jan. 31—Magnitude 4.0—5 mi (8 km) ENE of Pāhala, Island of Hawaiʻi

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There is no tsunami threat to Hawai’i following a 4.3 (4.1 preliminary) magnitude earthquake reported at 5:46 p.m. on Tuesday, July 26, in the SW rift zone of the Kīlauea Volcano on Hawaiʻi Island.

The USGS Hawaiian Volcano Observatory reports that this earthquake is part of the seismic swarm under the Pāhala area, which has been going on since 2019. Earthquakes in this region have been observed at least as far back as the 1960s, according to the HVO.

The HVO reports the earthquake had no apparent impact on either Mauna Loa or Kīlauea volcanoes.  

The Pacific Tsunami Warning Center says that no tsunami is expected, but some areas may have experienced shaking.

Within the first 20 minutes of the quake, “felt reports” were recorded in multiple locations on Hawaiʻi Island. It was also felt in Kula, Maui, according to reports filed with the USGS.

The HVO reports that there were 130 felt reports within the first half hour of the quake.

The USGS reports that locations near the quake include:

• Pāhala, Hawaiʻi: 6 mi WSW
• Hawaiian Paradise Park, Hawaiʻi: 36.8 mi NE
• Hilo, Hawaiʻi: 39.3 mi NNE
• Kailua-Kona, Hawaiʻi: 48.2 mi NW
• Honolulu, Hawaiʻi: 214.4 mi NW

*This post will be updated with more information as it becomes available.