Kilauea – Not the Peaceful Volcano We Thought
Kilauea is not what I thought!
All my life, I have been told that Hawaii’s volcanoes are of the peaceful type. They produce breath-taking fountains of lava and flow to the ocean via lava tubes or awe inspiring, cascading rivers of super heated rock towards the sea. Now, I’ve learned that this is not the case.
I just read a report from the annual meeting of the American Geophysical Union, stating that Kilauea actually has a history of prolonged periods of explosive eruptions! As a matter of fact, there are longer periods of explosive eruptions than peaceful interludes, such as Hawaii has experienced for the last couple of hundred years.
They also report that the explosive eruptions could resume at any time because they have no way of predicting any sort of timetable. From 500 to 200 years ago, it was primarily the explosive type of volcanic activity that marked Kilauea’s eruptions.
To quote from an article written by David Perlman and published on SFGate.com (San Francisco Chronicle):
“Eruptions and flows
“The geologic record shows that Kilauea’s activity has been marked by a period dominated by frequent lava flows from about 2,500 to 2,200 years ago, followed by a long period of explosive eruptions that continued for about the next 1,200 years; then another 500 years of lava flows, followed by about 300 years of eruptions, and then by more lava flows that continue today.
More than 100 radiocarbon observations, based on charcoal from the mountain’s burned vegetation, have established the dates, Swanson said.” [Donald Swanson of the U.S. Geological Survey and director of the Hawaii Volcano Observatory.]
The lava flows are building up the volcano’s summit now, he said, and each period of violent eruptions creates and deepens the volcano’s circular crater, called the caldera. When even a small eruption is about to occur, he said, the bottom of the caldera sinks slightly. So its level is recorded daily as a possible sign that an eruption is due.
“The good news is that we are currently in a period of frequent lava flows, and the hazard of explosive eruptions is small,” Swanson said. “The bad news is that we don’t know when the next period of deep caldera and explosive eruptions will start. We know too little to estimate recurrence intervals.”
Image of Kilauea Changed Forever
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