Hawaii town that has suffered 600 earthquakes a week sits on a chamber of unstable magma

Ignorance is bliss? Hawaii town that has suffered 600 earthquakes a WEEK for the last five years – 192,000 in total – is warned tremors are caused by huge chamber of unstable magma underground

  • Pahala in Hawaii has suffered from around 600 earthquakes a week since 2018
  • Seismologists used new techniques to reveal a web of magma under the town
  • The earthquakes are typically ‘micro’ quakes and not detected by people 

A small town in Hawaii that experiences an astonishing 600 earthquakes a week is being rocked by a concentrated pool of magma directly beneath it, a study has found.

The number of earthquakes recorded in Pahala, a town in the south of the Big Island of Hawaii, has increased 70-fold since 2015, and seismologists have used modern imaging techniques to attribute the sharp rise to a web of magma connected to a nearby volcano.

Pahala is a small town that had a population of around 1,500 at the time of the 2020 census and was once a home to a sugar plantation. According to the United States Geological Survey it is the ‘most seismically active area’ in Hawaii.

January is Volcano Awareness Month for the Island of Hawaii – established in 2010 to improve understanding of Hawaiian volcanoes. 

Pahala suffers an astonishing 600 earthquakes a week and is being rocked by a concentrated pool of magma directly beneath it, a study has found

Each dot on the map represents an earthquake that has been detected in the last month. Pahala is located beneath the cluster of dots at the south of Big Island

Each dot on the map represents an earthquake that has been detected in the last month. Pahala is located beneath the cluster of dots at the south of Big Island

Scientists at the California Institute of Technology have published a paper in the journal Science that provides a map of seismic activity beneath the island connecting Pahala to active volcano Kilauea.

The earthquakes affecting the town on a weekly basis have ranked between 1.7 and 3.0 on the Richter scale. Quakes with a magnitude of 2.0 or less are known as microearthquakes and not usually felt by people, according to the USGS. 

The amount of activity under Pahala increased dramatically in 2018 after a collapse of Kilauea caused a series lava flows that destroyed more than 700 homes. 

Those eruptions in turn triggered powerful earthquakes that saw its crater grow from around 100 to 500 meters deep. Kilauea remains one of the most active volcanos in the world. 

‘We leverage advances in earthquake monitoring with deep learning algorithms to image the structures underlying a major mantle earthquake swarm of nearly 200,000 events that rapidly accelerated following the 2018 Kilauea caldera collapse,’ wrote the scientists.

Footage from a livestream of Kilauea erupting on January 5. It is one of the most active volcanos in the world and about 20 miles from Pahala

Footage from a livestream of Kilauea erupting on January 5. It is one of the most active volcanos in the world and about 20 miles from Pahala

Seismologists have used modern imaging techniques to attribute the sharp rise to a web of magma connected to nearby volcano Kilauea. Black dots on this map denote earthquakes

Seismologists have used modern imaging techniques to attribute the sharp rise to a web of magma connected to nearby volcano Kilauea. Black dots on this map denote earthquakes

Not only that, the seismologists also identified a belt of magma connecting Pahala to another nearby volcano, Mauna Loa

Not only that, the seismologists also identified a belt of magma connecting Pahala to another nearby volcano, Mauna Loa

In 2019 around a year after the collapse there was a surge in the number of earthquakes beneath Pahala.  

‘At depths of 36-43 km, we resolve a 15 km long collection of near-horizontal sheeted structures that we identify as a sill complex. These sills connect to the lower depths of Kilauea’s plumbing by a 25 km-long belt of seismicity,’ they said.

Not only that, the seismologists also identified a belt of magma connecting Pahala to another nearby volcano, Mauna Loa.