USGS HVO Press Release - Magnitude-4.7 Earthquake Occurs During Swarm beneath Lō‘ihi Seamount

Release Date:

An earthquake of magnitude-4.7 (preliminary) was recorded by the U.S. Geological Survey's Hawaiian Volcano Observatory on December 7 at 1:42 a.m. HST.

The earthquake was centered about 8 km (5 miles) east of Lō‘ihi seamount at a depth of 28 km (17 miles). By the time of this release, no one had called the observatory to report that earthquake was felt or that damage to property was incurred.

The magnitude-4.7 earthquake occurred a few hours after a flurry of earthquakes began on December 6 at about 10:00 p.m. HST. The swarm consisted of a few dozen earthquakes and appeared to have ended by the time of this release.

Lō‘ihi seamount is an active volcano situated on the seafloor south of Kīlauea Volcano about 30 km (19 miles) from the shoreline of Hawai‘i island. The seamount is 969 m (3,180 feet) below sea level.

Two earthquakes occurred earlier this year beneath Lō‘ihi—a magnitude-5.2 earthquake on July 17 and a magnitude-5.1 event on May 13. These two earthquakes are the largest recorded in the general Lō‘ihi region since a magnitude-4.9 earthquake occurred on September 13, 2001.

In July 1996, during a large earthquake swarm, more than a thousand events were located beneath the Lō‘ihi area. Between July 27–28, 1996, nearly 700 events were recorded during a 24-hour period. After the swarm, scientists on submersible dives to Lō‘ihi concluded that the earthquakes were accompanied by a significant collapse of the summit area and an apparent eruption.

Daily updates about ongoing eruptions, recent images and videos of summit and East Rift Zone volcanic activity, maps, and data about recent earthquakes in Hawaii are posted on the HVO website at

USGS provides science for a changing world. Visit, and follow us on Twitter @USGS and our other social media channels

Subscribe to our news releases via RSS, or Twitter

Links and contacts within this release are valid at the time of publication.