A Geological Tour - Magnificent Locations of the United States

A Geological Tour: Magnificent Locations of the United States

Introduction

Human interest in nature is not a new concept. This interest has been going on as far back as history is recorded. The natural inquisitiveness of humans has led them to discover many natural geological wonders. These wonders did not have help from humankind nor did they need it. They are part of the earth; created from materials and minerals found just beneath the surface and from depths much greater.

Before we begin please understand that in geology, all things come from the earth in some shape, form, or fashion. As we prepare to embark on our journey it would be prudent for everyone to keep in mind that the places we are going to be visiting were made by the earth without intervention from humans. Hopefully, this tour will provide everyone a better understanding of why the study of geology is important. These locations provide a heartwarming contrast between living with the land and living on the land.

Our tour itinerary consists of three stops at geological wonders in the United States. First we shall travel to the astonishing Cascade Mountains in Washington State home of the active volcano Mount Saint Helens. Then off to the tropical Hawaiian Islands to walk along the black sand beaches of Punalu'u. We will be finishing the tour with a nourishing soak in the historic hot springs of Hot Springs, North Carolina.

Mount St. Helens

Mount St. Helens is located in Washington State nestled within the Cascade mountain range in the southwestern part of the state. The Cascade mountain range extends from Mount Garibaldi, British Columbia, Canada, to Lassen Peak in northern California. Formed from the subduction of the Pacific plate and the North American plate; the Cascades contain a few volcanoes. Of them is the youngest and most famous, Mount St Helens. (Tilling, Topinka, and Swanson, 1990)

Mount St. Helens is a composite volcano or in geologic terminology a stratovolcano. The term stratovolcano means that the mountain is steep-sided and often possesses a symmetrical cone. The cone construction consists of many layers of hardened lava flows, ash and other volcanic debris and tends to erupt violently. (Topinka, 2000) Some Indians of the Pacific Northwest called Mount St. Helens "Louwala-Clough," or "smoking mountain." due to its constant activity throughout history. (Tilling, Topinka, and Swanson, 1990) The mountain was even called the "Fujiyama of America." due to its remarkable resemblance to Mount Fujiyama in Japan. But the name we have come to know it by was given in 1792 by a British Royal Navy Captain by the name of George Vancouver. He named Mount St. Helens in honor of the British Ambassador to Spain, Baron St. Helens. (Tilling, Topinka, and Swanson, 1990)

On May 18, 1980, Mount St. Helens became famous when it awoke from its 123 year sleep. In true composite volcano form, this eruption was the largest of any volcano in the United States in the 20th century. Its Volcanic Explosive Index or VEI as classified as 5. The Volcanic Explosive Index is the measurement index for volcanoes much like the Richter Magnitude Scale is to earthquakes. The VEI scale ranges from 0, which is considered a non-explosive eruption, to 8 which are very large explosion. Although the explosion killed only 57 people the most extensive damage was done to the environment. The eruption created a debris avalanche that was traveling somewhere between 110 -150 mph engulfing 24 square miles of forest, lakes, and valleys. Along with the avalanche of debris, a mushroom cloud of ash was created that extended 12 miles into the sky turning day to night. The total eruption lasted just 9 hours. Another 48 hours passed before the ash clouds defused enough for light to be permitted through. (Tilling, Topinka, and Swanson, 1990)

It has been almost two decades since Mount St. Helens erupted. The tresses have re-grown denser and fuller due to the mineral rich soil that was released during the eruption. The wilderness surrounding the mountain is bustling with wildlife once again. One might find it hard to imagine that even though Mount St. Helens looks dormant it is still very much active. In the report from the United States Geological Survey dated April 1, 2007, the lava dome inside of the crater is growing along with the release of low emissions of steam and gas. Seismic activity has also been recorded from beneath the mountain but currently there are no concrete predictions of when the next eruption will occur. Mount St. Helens remains on the geologists' volcano watch list to establish a pattern of activity in hopes to prevent further loss of life. (United States Geological Survey Recent updates for US volcanoes: Mount St. Helens)

Mount St. Helens is one of the many volcanoes that are present on the Earth. Although it is relatively young, Mount St. Helens has established a place in American Geological history with the eruption of 1980. From "smoking mountain" to today's Mount St. Helens, the beginning points us in the direction to predict the end.

Now it is time to move on to our next wondrous geological location on the lovely Hawaiian Islands.

Black Sand Beaches of Punalu'u

White and light brown are the colors normally associated with beaches. There is another color that is widely frequented by tourist to the Island of Hawaii. The black sand beaches of Punalu'u are a frequent tourist attraction to those visiting the island.

The black rocky cliffs and fine sand beaches were created from lava flows that cooled when they reached the ocean. Punalu'u is located in the Hawaii Volcanoes National Park. This park became the 1st national park of any United States territories in 1916 by President Woodrow Wilson. President Wilson agreed with Congress that "Scientifically and popularly, the volcanoes are a national rather than a local asset, and the opinions of travelers appear to be unanimous that this area is of national importance for park preservation." (Castro, 1953) For the most part, travelers during this time focused on the volcanoes and not the beaches that the lava had created.

When the volcanoes would erupt, the lava would flow to the oceans and instantly cool forming tiny shards of black glass or cliffs of black rock. Over many years erosion from the seas waves created the beaches that we are standing on today. This beach is predominantly composed of the iron rich mafic rock that was once lava. Years of erosion, both chemical and physical, has reduced the mafic rock to sand like particles. With its low silica content, the mafic rock is darker in color than the normal golden brown silica