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The visit to Mount St. Helens is actually one of the many optional field trips that is part of the program for the geography module i'm taking. Each field trip is led by one teaching assistant and it is considered 'free' cause transportation and admission charges are covered by the additional course fee (US$40) i had to pay for this course. So if i want, i could attend all the field trips (abt 9 of them) and get to travel for free.. :):)
Met up with the group of students attending the field trip at 7a.m and off we go! Transportation in the form of vans (seating capacity abt 12) were provided by the school and the drivers were students who were also gg for the field trip. But i just went and sat in the van that is driven by the TA.. safer.. :p However from the time we set off, it is obvious that the weather is not very good... black clouds and rain..
After 2+ hours drive, we finally reach the area near Mt. St. Helens. But too bad because of rain, there was a lot of fog and the volcano could not be seen :(:( If the weather was good, i would have taken lots and lots of nice pictures cause we went to a few points that provided excellent views during clear days. So not much pictures were taken (for once..) But i have found some pictures online for your viewing (and mine too!) :):):)
a dome shape volcano
Normally, volcanoes would erupt upwards. But for Mt St. Helen, it erupted sideways. This was due to an earthquake that cause the north side of the mountain (that was already bulging due to magma pushing up within the peak) to collapse resulting in a massive debris avalanche.
This debris avalanche swept away thick forested areas like twigs. The magma inside St. Helens then erupted out and burst forth into a large-scale pyroclastic flow that followed the path of the debris avalanche, going over valleys and into lakes in the area. This formed Lahars (volcanic mudflows consisting of ice, snow, water and any other debris that is picked up along the way) which was very deadly as it could travel for very long distances.
-Toutle River-
This river is 35 miles (56.3km) away from Mt. St. Helens but it was still hit by lahar that arrived 12 hours later after the eruption at 90 degrees.
Sidenote: Lots of salmon swimming upstream here.. cos saw a lot of fishermen with bagfuls of their catch.
Due to the lack of ground cover after the eruption, much more soil particles (as compared to before) were washed into the Toutle River, clogging up the Toutle, Cowlitz and Columbia River. Therefore a Sediment Retention Structure was built along the Toutle River to slow down the water flow so that sediments can be deposited at the small lake that is created at the structure, and the water that flows out would contain lesser sediment. However, this structure would most likely be fulled by 2035.
After entering the Mount St. Helens National Volcanic Monument, an area around the volcano that is preserve to let nature take its own course to return to its original state (even though some trees were planted) and for scientists to do testing, we went to see hummocks. Mounds that have a chunk of volcano inside them, and are caked on the outside with mud. (no pictures though.. it was raining quite heavily then and don't want to wet my camera)
On normal days, Mt. St. Helens would be the backdrop of this picture.
After that, we headed back to UW. The fieldtrip was suppose to end at 7p.m but we ended up reaching school at 4p.m. Lots of hikes could not be done cause the rain was making the place very cold and wet. See the above picture of me, i was wearing 2 more layers of clothes inside! total 5 layers! and was feeling just rite...
Overall, disappointed abt not being able to see the Mt. St. Helen but did learn some stuff. Hope the other field trips would not be that cold and wet!
Photoes courtesy of:
http://vulcan.wr.usgs.gov/Volcanoes/MSH/Images/MSH80/framework.html#spring_1980
https://www.nwp.usace.army.mil/op/srs/srs.asp
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