Monday, July 16, 2012

Mt. St. Helen's photos -- May 2012

We visited Mt. St. Helen's in southwestern Washington in May.  This is what the mountain looks like now. The entire top third of the mountain came off.  It used to be a perfect volcano cone.  The main portion of the top slid down at over 150 miles per hour, and slid up to seven miles away. Hot gasses, pulverized rock and lava were blown beyond the mountain top.




Here we are at the Visitor's Center, which was built after the eruption. David Johnston, the vulcanologist who was killed was monitoring the steaming and smoking volcano at this site which is 6 miles from the volcano. He was one of the principal scientists on the monitoring team and was manning an observation post here. He was the first to report the eruption, transmitting the message "Vancouver! Vancouver! This is it!" before being swept away by the lateral blast created by the collapse of the mountain's north flank. The Visitor's Center is named in his honor.

This is a tree trunk on display in the Visitor's Center.  The power and force of the blast killed everything in its path.  This tree remained rooted but its top was broken off and hurled down the mountain.  The bark still remained on the side away from the blast, but was completely stripped on the blast side.

The force of the blast buried this tree in the ground miles away.  Looking at the hillsides in the blast area in the 7 mile range from the mountain, trees were neatly blown over so that they all lay with their tops pointing away from the blast.  Nature can be unbelievable powerful.  The town of Valdez, Alaska which we visited in June was completely wiped out by the 1964 earthquake.  It leaves us in awe.

FYI: Here is an abbreviated Wikipedia description of the eruption:

The 1980 eruption of Mount St. Helen was a major volcanic eruption. An earthquake on Sunday, May 18, 1980, caused the entire weakened north face to slide away, suddenly exposing the partly molten, gas- and steam-rich rock in the volcano to lower pressure. The rock responded by exploding a hot mix of lava and pulverized older rock toward Spirit Lake so fast that it overtook the cascading north face. An eruption column rose 80,000 feet (24,400 m) into the atmosphere and deposited ash in 11 U.S. states. At the same time, snow, ice and several entire glaciers on the volcano melted, forming a series of large volcanic mudslides that reached as far as the Columbia River, nearly fifty miles (eighty kilometers) to the southwest. Fifty-seven people and thousands of animals were killed. Hundreds of square miles were reduced to wasteland. Mount St. Helen's was left with a crater on its north side.


Sally & Bill

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