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Mt. St. Helens Explosion ~ 40 years ago !!!

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  • Mt. St. Helens Explosion ~ 40 years ago !!!

    March 27, 1980 = 40 years ago, and on this Friday, the start of a sequence such that on May 18th .... the 40th year "anniversary" of such eruption/explosion!!!.

    Likely means little to nothing to the majority of members here whom don't live on the "Pacific Rim"/"Ring of Fire" within a State that contains a few volcanoes, most classified as "Dormant" --- BUT---

    ... If you happened to have been around in this area of the PNW about 40 years ago this was an item of concern, a sort of "Emergency Management" potential ~~~~~ which became an EM actual for many locals here abouts.

    Fortunately I lived a few score miles North and prevailing winds of the time blew towards the East, so smoke, dust, etc. flew and fell that way; still it was an impact that was/ and could have been; of more significant impact than the current pandemic and the sort of "Natural Disaster" that has dominated "Emergency Management" thinking and contingencies ever since ~~~ FWIW.

    1980 eruption of Mount St. Helens

    The 1980 eruption of Mount St. Helens was a series of volcanic explosions and pyroclastic flows from Mount St. Helens in Skamania County, U.S. state of Washington, that began on March 27, 1980. It initiated as a series of phreatic blasts from the summit then escalated on May 18, 1980, as a major explosive eruption. The eruption, which had a Volcanic Explosivity Index of 5, was the most significant to occur in the contiguous 48 U.S. states since the much smaller 1915 eruption of Lassen Peak in California.[2] It has often been declared the most disastrous volcanic eruption in U.S. history. The eruption was preceded by a two-month series of earthquakes and steam-venting episodes, caused by an injection of magma at shallow depth below the volcano that created a large bulge and a fracture system on the mountain's north slope.

    An earthquake at 8:32:17 a.m. PDT (UTC−7) on Sunday, May 18, 1980, caused the entire weakened north face to slide away, creating the largest landslide ever recorded. This allowed the partly molten, high-pressure gas- and steam-rich rock in the volcano to suddenly explode northwards toward Spirit Lake in a hot mix of lava and pulverized older rock, overtaking the avalanching face.

    An eruption column rose 80,000 feet (24 km; 15 mi) into the atmosphere and deposited ash in 11 U.S. states[3] and significant ash in two Canadian provinces.[4] At the same time, snow, ice and several entire glaciers on the volcano melted, forming a series of large lahars (volcanic mudslides) that reached as far as the Columbia River, nearly 50 miles (80 km) to the southwest. Less severe outbursts continued into the next day, only to be followed by other large, but not as destructive, eruptions later that year. Thermal energy released during the eruption was equal to 26 megatons of TNT
    TANSTAAFL = There Ain't No Such Thing As A Free Lunch

  • #2
    I bring up and remind of this sort of subject because for those of us* actually involved in and active with local "Emergency Management" structures such as C.E.R.T. or 'FEMA' ... we already have a "triage" of response prepossesses in place and pandemics tend to be a few down the list because the "others"** can be more sudden/unexpected and have greater and more quick impact and results whereas "pandemics" usually have a longer timeline of impact and result containment***.

    * = As I've mentioned a few times in past sub-forums/threads here; I've been througha few training programs with local EM agencies and their versions of CERT. Best I've noticed, few to none others on this forum/board have similar training/linkage/involvement in actual 'Emergency Management' structures/organizations.

    ** = "Others" being either "Natural Causes" such as eruptions/earthquakes/Tsunamis/Etc. ; or "human caused" such as Global Warfare/Nuclear Strikes/EMPs/Civil Disruptions/Etc. ...

    *** = Pandemics usually occur over a span of days-to weeks-to months rather than within seconds to minutes; hence the assessment and response structures time-frames are far more 'stretched out' and able to be more accurate and tailored.
    TANSTAAFL = There Ain't No Such Thing As A Free Lunch


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