Magnitude-4 shaker strikes south of Mauna Loa’s Northeast Rift Zone

Doug Enz didn’t immediately put two and two together when the ground shook under him Saturday morning at his Volcano home. He instead thought he’d be making a call about an issue in his garage.

“It happened exactly when I was opening my garage door,” wrote Enz in a reply to a post in the Hawai‘i Tracker group on Facebook. “I was like, ‘Dang … gonna have to call the repair man.'”

Enz shared a laugh in his comment, too, since soon after he realized it might be jumping the gun with the repair man as it was actually an earthquake that rattled him and his garage.

More than 180 people — most from around the Big Island and one from as far away as Honolulu — had reported feeling the magnitude-4 quake by 12:50 p.m. Saturday.

Hawaiian Volcano Observatory said the temblor struck the island at 8:40 a.m. Saturday, 11 miles west-northwest of Volcano Village at a depth of 13 miles below sea level.

The epicenter was near the top of Mauna Loa Road, which reopened this week from Kīpukapuaulu to the 6,667-foot Mauna Loa Lookout inside Hawai‘i Volcanoes National Park.

Hawaiian Volcano Observatory reported the quake happened south of Mauna Loa volcano’s Northeast Rift Zone, adding it was unrelated to magmatic activity and also had no apparent impact on either Mauna Loa or Kīlauea volcanoes.

Only light shaking was reported by the community and seismic instruments. No damage to buildings or infrastructure was expected.

Aftershocks are possible in the coming days and weeks.

Stephanie Muller Terlep told her fellow Hawai‘i Tracker group members that it was a brief shaker, only her bed moved. Jo Piltz of Waimea added in a comment to the group that he heard it more than she felt it.

Lauren Butcher of Pa‘auilo replying to a comment by Judy Henkel on a post in the Waimea Insiders group on Facebook group said the quake “just rolled through” and was very short in outer Pa‘auilo.

“We’re having earthquakes and a lot of them,” wrote Christine Inserra of Kaʻū, administrator and a top contributor of the Hawai‘i Storm Chasers group on Facebook, mentioning Saturday morning’s shaker as a magnitude-3.9 quake before it was updated to a magnitude-4. “Almost around the entire mother mountain [Mauna Loa].”

Inserra added that quakes have happened often during the past couple of days in the Volcano-to-Pāhala and Nāpōʻopoʻo areas.

Hawaiian Volcano Observatory does indeed show as of 2:15 p.m. Saturday there had been at least 36 temblors of various magnitudes in various locations on the Big Island during the past 2 days.

That includes one near Hōnaunau-Nāpōʻopoʻo, several around Pāhala and several around Volcano other than Saturday’s magnitude 4.

Earthquake rates during the past week beneath Kīlauea volcano’s summit and upper East Rift Zone also more than doubled this week from the previous week.

Hawaiian Volcano Observatory’s weekly “Volcano Watch” article reported in its volcano activity update this week that About 100 earthquakes were located beneath the summit and about 226 in the upper East Rift Zone.

Data from the volcano observatory showed that from Oct. 1 through 1:45 p.m. Nov. 30, a total of at least 481 earthquakes of varying magnitudes had happened on or around the Big Island at various locations and depths.

Here’s a breakdown of those earthquake numbers by magnitude:

• Less than magnitude-1: 10.
• Magnitude-1 to magnitude-2: 256.
• Magnitude-2 to magnitude-3: 204.
• Magnitude-3 to magnitude-4: 8.
• Magnitude-4 to magnitude-5: 3.

Hawaiian Volcano Observatory continues to monitor Hawai‘i volcanoes for any changes.

Click here to find additional information from the U.S. Geological Survey about Saturday’s earthquake and others.