Geography 2240A/B Chapter Notes - Chapter 6: Pumice, Seismometer, Eiffel Tower
7 Apr 2015
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Saw cracks that indicated that the volcano was moving (crack gets bigger as the day goes on). Setup time lapse camera on a nearby ridge learned that dome was rising. Oozing sticky gray lava cooling as it reaches the surface. Watched process of dome building in front of their eyes. Set up seismometers to detect tremors placed series of these as close to lava dome as possible. One eq after another, seismic cycle is continuous. lava on and off the move forcing its way through the ground. (couple of days) then eq series would occur. At one time dome reaches 1000 ft. in 1986 seismographs go quiet. Found a flash of colour a prairie lupine plant (usually high slopes of mt st helens) Plant grew b/c special root structure that provides its own fertilizer (nitrogen to plant and plant provides bacteria through sugars done by photosynthesis). Black water with gases. hot springs coming up.
