Mount St Helens 18 May 1980 eruption Mount St Helens 18 May 1980 eruption.

Slides:



Advertisements
Similar presentations
1980 Eruption Before, During and After
Advertisements

MEDC Case Study - Mount St.Helens, USA
Volcanoes Welcome to Washington - the 42 nd State.
Mount St. Helens By Annie Crutchley.
The Eruption of Mount St Helens, 18 th May The Cascade Range is a volcanic chain stretching from northern California to British Columbia.
The Mt St Helens Eruption May 18, 1980 Where is it? Mount St Helens in the USA has been one of the most covered volcanoes in recent years. In 1980, witnesses.
May 18, 1980 Eruption. Before May 18, 1980 Spirit Lake.
Mt. Pinatubo By: Kirsti Max Max Shelby Shelby Mt. Pinatubo.
Mount St. Helens Washington State
VOLCANOES Mt. Arenal – Costa Rica. It’s all in the magma… Mafic or Felsic ? Mafic – rich in ferromagnesian minerals, flows easily (low viscosity), gas.
Volcanic Hazards Landslides Ash fall Pyroclastic flow Lahar Lava flow.
Mount St Helens by Alice Graham. Location of the volcano and background history A volcanic peak, 2,549 m (8,363 ft) high The mountain is 6 miles (9.5.
Mount St. Helens By: Chuck Wolfe Chris LaPlante Matt ‘Chang’ Madden.
1. One half of the radioactive potassium-40 (K 40 ) in an igneous rock has decayed to argon-40 (Ar 40 ). According to the ESRT, about how many years ago.
Volcaniclastic Sedimentation and Facies. The Interaction between Volcanism and Sedimentation Active volcanism produces abundant sediment that is rapidly.
Volcanic processes. Pyroclastic deposits & lava flows.
Today: Chapter 6 Volcanism
Volcanoes A Hot Topic.
Volcanoes A Hot Topic. What is a volcano? A mountain formed by lava and/or pyroclastic material.
Volcanic Hazards in the U.S.. Outline Cascades –Mt. St. Helens –Mt. Rainier –Crater Lake –Mt. Shasta –Lassen Other eruptions –Yellowstone –Long Valley.
Volcanoes.
Mount St Helens, USA, 1980.
The Eruption of Mount Saint Helens Made by Electra Nicolaysen Fernando III El Santo Monday, 16 December 2013.
Let’s Learn More About Pompeii Click on the images below!
Mount Pinatubo, Philippines Zoe Rose. Causes of the volcanic eruption On July 16, 1990, a magnitude 7.8 earthquake (comparable in size to the great 1906.
And other Plinian Eruptions
Volcanic Hazards p , web reading
Lecture 5 Volcanism. Lecture Outline ICharacteristics of Volcanoes IITypes of Volcanoes A)Shield Volcanoes i.Description ii.Composition iii.Eruption Features.
Volcanoes and Other Mountains
Volcano Eruptions ~ What comes out of a volcano when it erupts?
Mt. St Helens Eruption and present day activity
Mount St. Helens April 10, On March 20, 1980, after a quiet period of 123 years, earthquake activity once again began under Mt. St. Helens. March.
Volcanoes. Parts of a Volcano magma chamber: a large reserve of magma that collects deep underground central vent: long tunnel which lava is pushed through.
VOLCANOES Chapter 13 Part 2. IV. Types of Volcanoes e.g. Hawaiian Islands are examples of Shield Volcanoes A. Shield Volcanoes 1. Eruption: Non-explosive.
MAGMA is molten rock, but is not just liquid - also contains bits of rock crystals and gas. It ranges in consistency from wet concrete to thick oatmeal.
Volcanoes. l Evidence that we live in an active planet l The gods of the underworld l Millions of people live near active volcanoes –The greatest geological.
MOUNT SAINT HELENS BY SHANJESSICA PRINCESS KHALIA.
Volcano Types and Volcanic Eruptions.
Mount St. Helens We are here.
Volcanoes & Volcanic Activity By Philipp S., 3 rd hour.
Lesson 27 What are volcanoes?.
Tuesday: bring calculator. Mt. St. Helens: A Case Study from 1980 Photo pre-eruption.
Tectonic Activity Volcanoes –Cone Volcanoes –Shield Volcanoes –Composite Volcanoes –Human effect of Volcanoes.
The Eruption of Mount Pinatubo June The second-largest volcanic eruption of the last century, and by far the largest eruption to affect a densely.
Mount St Helens By Ashleigh and Abi!. Mount St Helens March 1980 sign that the volcano was going to erupt. Earthquakes alert positive eruption. USGS.
Mount St. Helen’s By: Stephanie Graves Mount St. Helen’s is located in the state of Washington.
Rock melts when the temperature within the earth (geotherm) exceeds the melting point (solidus) of rock. This happens for different reasons at (1) subduction.
Mt. St. Helens, Washington. Plug Cascades Bomb Aerodynamically shaped.
Mount St. Helens The Eruption. Where is Mount St. Helens? Mt. St Helens is in Washington state 96 miles (154km) south of Seattle and 50 miles (80km) north.
BY RHIANNON AND RACHAEL. An eruption of hot volcanic ash rose 80,000 feet (24,400m) into the sky. At the same time, ice, snow and several glaciers which.
Before the May 18, 1980, eruption, the streams on Mount St. Helens were crystal clear. After the eruption, streams were choked with rock.
Volcanic Hazards. LAVA Lava often poses the least risk in an eruption Lava often poses the least risk in an eruption It is partly the thickness of the.
Lava flow Lahar Volcanic Hazards Landslides Ash fall Pyroclastic flow.
1 Natural Disasters Volcanoes: Materials & Effects.
Earth Science Introduction
Warm Up: Copy the question in your warm up section of your binder. 1
Mt. Rainier Tectonic Setting
Mt. Rainier.
Tectonic Activity Volcanoes Cone Volcanoes Shield Volcanoes
ERUPTION OF MT. MAYON The Philippines May 7, 2013
VOLCANIC ACTIVITY Unit 2 - Ch 10.
Cascade Volcanoes There are 13 potentially active volcanoes in the Cascade Range of the northwest-ern United States.
Volcanic Hazards! Volcanic Hazards!.
What Makes an Eruption Explosive?
Volcanic processes.
Tectonic Activity Volcanoes Cone Volcanoes Shield Volcanoes
VOLCANOES.
What determines the Characteristics of lava?
Volcanoes Mt. Etna, Sicily, Italy August 5, 1997 with city lights.
Mt. Rainier Tacoma, Washington in the foreground – 211,000 people.
Presentation transcript:

Mount St Helens 18 May 1980 eruption Mount St Helens 18 May 1980 eruption

The beast sleeps...

On 20 March 1980, after a quiet period of 123 yr, earthquake activity resumed. Small phreatic (steam) explosions began 7 days later.

Bulge developed as magma pushed up within the peak. It grew at up to 1.5 m/day. By May 17th it had inflated by 135 m.

at 08:32, 18 May …B A N G ! (get out now)

Ash plume erupted for > 9 hours Reached miles high Rolled east, averaging 60 mph.

5 miles

Horseshoe crater from NE

Volcanic ash deposited several 100 miles downwind. Noticeable ash fell in 11 states. Total volume of ash ~1 cubic km before compaction by rainfall.

Trees flattened by lateral blast

Debris avalanche travelled ~24 km downstream at >150 mph. It left behind 2.3 cu km of a hummocky deposit with avg. thickness of 45 m and max thickness of 180 m.

Mudline left by lahars (volcanic mudflows)

Lahar from 19 March 1982 eruption

More than 200 homes and over 185 miles of roads were destroyed by the 1980 lahars.

At least 17 separate pyroclastic flows descended the flanks of Mount St Helens during the 18 May eruption. Typical flow speed > 60 mph, Typical temperature > 400°C.

Pumice blocks at toe of pyroclastic flow

The action continued... 5 more explosive eruptions during

After the May 1980 eruption... Activity continues, erupting DOMES

300 m wide 34 m high (9 storeys) 1980

Dome growth via stubby lava lobe, extruding from a “spreading centre”. Lobe growth rate 1-3 m/hr. 1981

400 m wide 163 m high (44 storeys) 1981

By 1990, the dome had replaced 3% of the volume removed by the 18 May 1980 eruption. At this rate it will take over 200 years to rebuild Mount St Helens to its pre-1980 size. 1983

1984

800 m wide 230 m high (66 storeys) 1985

…dome glowing in the moonlight 1986

Before…

…after

Seattle and Mt Rainer Who’s next?