St Helens eruption in 1980 - photo RGBowen / The Oregonian
On May 18, 1980 , Mt St Helens exploded ravaging the countryside.
Photos innédites, recently published by geologist Ricahrd Bowen, taken during an overflight of the volcano , accompanied by his daughter Tara , 11 years old at the time.
As Sam Knapp, the Cessna 172 pilot said : " we were as close as you could be and survive ! "
During this anniversary, St Helens reminds us of its status as an active volcano.
" The One " from The Oregonian newspaper of 19.05.1980 , the day after the eruption - doc. The Oregonian archives
St Helens - a new explosion on 07.22.1980 / 7:02 - R.G. Bowen Photo / The Oregonian
The CVO , in charge of the Cascade Range volcanoes, revealed the results of monitoring at all times, on .
For the period 2004 - 2008 , a new dome was built , and scientists have noticed a " subtle inflation " , along with a minor seismic activity ... the magma chamber of St Helens is held to pressurize slowly again . This phenomenon is caused by an inflow of a small amount of magma at 4-8 km. below the surface.
This does not mean that the volcano is about to erupt ... the re- pressurization of the magma chamber of a volcano is observed on various buildings after an eruption , and may continue for years without eruption .
This summer, field work will include measuring the types and amounts of gases being released, and the strength of the gravity field at the volcano.
Map of horizontal displacements (GPS monitoring) between 2008 and 2014 - doc . CVO / M.Lisowski
Sources :
- The Oregonian - Mount St. Helens eruption: Rare aerial photos never seen before, shot after the 1980 eruption - link
- CVO - Cascades Volcano Observatory / USGS - Monitoring Techniques Provide Insight into Mount St. Helens Behavior - link
- KOIN 6 - The mountain continues to captivate since the 1980 eruption - link
