Sunday, January 11, 2009

Volcano Musings

My husband and I tend to be interested in many things. Volcanoes are amazing things. We've been blessed to see a number of volcanic areas. My fascination with the current Yellowstone earthquake news dates from volcano stories from my childhood.

I grew up on stories of Pompeii. For one thing, my mother visited Pompeii on her trip to Europe in the late 1930's and told me stories of her visit. We had a copy of Richard Haliburton's Book of Marvels." My favorite chapter was the one about Pompeii - the volcano that erupted and buried a city that stayed lost for 1700 years and then only found by accident.

In my growing up year, as we drove to Colorado to spend time in the mountains and visit relatives, we regularly passed by Mount Capulin in New Mexico. It was only as a teenager that I finally took the circular drive to the top of the cinder cone. While taking trips with our children, we would stop and picnic at the Valley of Fire in New Mexico and marvel at the hardened lava flows there. When we lived in South Austin, we often passed by Pilot Knob, the remnants of an old, extinct volcano. The rocks around McKinney Falls were hardened by this volcano's activity creating rock formations that give us these beautiful falls.

In 1980, we listened to the news reports as the earthquake activity increased around Mount St. Helens. It was an amazing opportunity for scientists to study changes in an active volcano. We have so much equipment today to try to understand how volcanoes work and to learn to predict eruptions so we can evacuate people and save lives. While there were obvious expectations that something big was about to happen, when Mount St. Helen erupted, we were awed by the power and devastation we could see with the amazing still photos and the TV coverage. We visited Mount St. Helens in the late 1980's after its eruption in 1980. It was amazing to see how the pyroclastic flow went up and down the hills, knocking down all the trees in its path for miles and miles and miles. When we were there there was a small dome forming in the crater. Flowers were growing in the ash. I would love to go back and see how much vegetation has recovered almost 30 years later. We went to the summit of Mount Ranier and enjoyed seeing the volcanic peaks in northern Washington State.

On our Alaska trip we noted a smoking mountain and identified it as an active volcano even before the road sign noted it as the volcano, Mount Redoubt.

On our 25th anniversary cruise, we stopped on the Caribbean island, St. Lucia and toured the drive through volcano. We noted the similarity the thermal features shared with Yellowstone National Park.

Around the year 2000 we went to Hawaii and included the Big Island. We stayed at a guest house on the slopes of the volcano. We drove to the crater and down to the ocean where the lava hits the sea. We saw ancient lava tunnels and an "eye" into an existing tunnel. We took a helicopter ride over the crater and the red "eye".

On one of our trips to France, we spent the night near the Parc Naturel Regional des Volcans d'Auvergne. Our hotel was built into one of the volcanic cones and overlooked a valley filled with other volcanic cinder cones.

While I am not enough of a volcanologist or a geologist to know exactly what kind of volcano I'm visiting without reading the signs, I do know there are several kinds of volcanoes - cinder cones, composite volcanoes, shield volcanoes,and lava domes. I have not found the reference for it yet, but I suspect that volcanoes that form calderas are probably still a different type of volcano. The USGS webpage, Principal Types of Volcanoes has some great photos and explanation describing the differences between these types of volcanoes.

The term super volcano is relatively new phraseology. A different USGS information page says, "It was used by the producers of a British TV program in 2000 to refer to volcanoes that have generated Earth's largest volcanic eruptions. As such, a supervolcano would be one that has produced an exceedingly large, catastrophic explosive eruption and a giant caldera. Examples of volcanoes that produced exceedingly voluminous pyroclastic eruptions and formed large calderas in the past 2 million years would include Yellowstone, Long Valley in eastern California, Toba in Indonesia, and Taupo in New Zealand. Other "supervolcanoes" would likely include the large caldera volcanoes of Japan, Indonesia, Alaska (e.g., Aniakchak, Emmons, Fisher), and other areas."

One of my nexts posts will be to look at some of these previous "super volcanoes" and how Yellowstone's previous eruptions compare. I really don't believe that the current evidence from the Yellowstone earthquakes is pointing to a super volcanic eruption. I don't want to be a doomsday predictor. But I am fascinated with the natural world that God created. There are so many things in nature - hurricanes, earthquakes, volcanoes, tornadoes, etc over which man has no control. We can study them, we can learn to make some predictions about them, we can take shelter from them, we can run from them, but we can't prevent them. They are more powerful than anything man can make. They remind us of how small we really are in this vast universe. I find it amazing that there are so many different types of volcanoes around the world. There are people whose life work is either studying or photographing volcanic eruptions. And, yes, some of these people die when they end up too close and in the wrong place during an eruption. But they leave a legacy of information that helps us better understand how volcanoes work.

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