Simply defined, a volcanic eruption refers to an eruption of a body’s (such as the earth) crust that is accompanied by things like hot lava, gases, and volcanic ash. Volcanic eruptions on earth take place due to breakages in the tectonic plates floating in the mantle of the earth. For this reason, volcanoes on earth tend to be located in regions with such breakages or places where there is a divergence or a convergence of these plates. A good example of a convergence of tectonic plates is at the famous region known as the Pacific Ring of Fire. A divergence of tectonic plates exists in regions like where there is a mid-oceanic ridge like the Mid-Atlantic Ridge. Other places where volcanoes can form include a stretch in the earth’s crust or a thinning. In the United States, there are approximately 200 active volcanoes located in 12 states. Alaska is home to 141 active volcanoes, the most of any US state. Other states include California, Oregon, Washington, and Hawaii among others.
The state of Hawaii is part of the Hawaiian-Emperor Seamount chain, which extends all across the Pacific Ocean. The chain has three sections namely the Hawaiian archipelago (the Windward isles), the Northwestern Hawaiian Islands (the Leeward isles), and the Emperor seamounts. The state of Hawaii is part of the first section of the chain. Volcanoes in the state of Hawaii include the likes of Haleakalā or East Maui Volcano (10,023 feet), Mauna Loa (13,679 feet), Mauna Kea (13,796 feet), West Maui Volcano (5,788 feet), and others. Active volcanoes include Mauna Loa, Kilauea, and Hualālai. Mauna Loa is arguably the world’s largest active volcano and has been erupting for around 700,000 years. The last major eruption took place between March and April 1984.
Among the active volcanoes, Kilauea is the most active with its eruptions starting from 1983 to this day. Part of the Hawaii Volcanoes National Park, Kilauea has a height of about 4,091 feet and an age that is about 600,000 years. Within the Hawaiian hotspot, this volcano is among the youngest as well as the most eruptive. This shield volcano was once thought to be part of the more prominent Mauna Loa due to its lack of prominence and coinciding volcanic action. Kilauea has caused considerable damage since its eruptions began in 1983. For example, a massive eruption in 1990 destroyed the town of Kalapana while an eruption in 2018 destroyed Vacationland Hawaii. In addition, May 2018 saw the lower Puna eruption that lasted for several weeks and was accompanied by an earthquake of a magnitude of 6.9. About 2,000 people had to evacuate from areas like the Leilani Estates subdivision.
Washington’s volcanoes include the likes of Battle Ground Lake, Marble Mountain-Trout Creek Hill volcanic zone, Mount St. Helens, White Chuck Cinder Cone, and others. Also known as Louwala-Clough, Mount St. Helens is part of the Cascade Volcanic Arc, which is part of the Pacific Ring of Fire. Mount St. Helens is one of the most famous volcanoes after its massive eruption back in 1980. This eruption is the still the most destructive and deadliest in the volcanic history of the US. The final tally of the eruption stood at 57 deaths and destroyed 47 bridges and 250 homes. In addition, about 185 miles of highway and 15 miles of rail were destroyed. The avalanche that came after the eruption led to the reduction of the mountain’s summit from 9,677 feet to 8,363 feet. Recently, between 2004 and 2008, the mountain had some volcanic activity. Data shows that Mount St. Helens is also due for another eruption although not on a smaller scale to that of 1980.
Oregon has more than 30 volcanoes although most of them are dormant having erupted thousands or millions of years ago. These include the likes of Bald Mountain Caldera, Mount Bachelor, Columbia River Basalt Group, Crooked River caldera, Wildcat Mountain Caldera, and others. The most recent eruption came back in 1996 from Gorda Ridge, which has a height of -9,842 feet. Just like California above, the state of Oregon also has a number of high-risk volcanic sites including the Three Sisters, Newberry Volcano, Crater Lake, and Mount Hood. Despite a universal acceptance that the state will definitely experience a volcanic eruption, experts agree that the eruption will not necessarily happen in the near future.
California has plenty of volcanoes (due to the multitude of fault lines on the Pacific Ring of Fire the state sits on) although most of them are dormant. Some of these volcanoes, such as Pinnacles, Malapai Hill, and Round Top, had their last eruptions at least 10 million years ago. Some of the more recent eruptions came from volcanoes such as Lassen Volcanic Center and Lassen Peak, both of which had eruptions in 1917. In the case of the Lassen Volcanic Center, the potential remains for renewed volcanic action that could be potentially destructive to human life.
In 2018, the California Volcano Observatory (CVO) released a report that details the volcanoes in the state with the highest chances of an eruption. Of the nineteen listed volcanoes, the three volcanoes with the highest risk include the aforementioned Lassen Volcanic Center as well as Mount Shasta and the Long Valley Caldera. The CVO further reported that these three blast volcanoes are even more dangerous than Hawaii’s volcanoes, which are not blast volcanoes.
The state of Alaska also has a number of volcanoes. In fact, according to the Alaska Volcano Observatory, Alaska has the largest number of volcanoes in the US that have the potential of becoming active. Fortunately, most of the volcanoes are not located close to populated places so most of these volcanoes pose no real threat to human life.
Some of the more active volcanoes in Alaska include Bogoslof Island (2017), Mount Augustine (2005), Mount Cleveland (2017), Fourpeaked (2006), Kasatochi Island (2008), and others. However, some of them, such as Mount Cleveland, pose a threat to airplanes whose routes are over the mountain.
Mount Okmok, which is also located in a remote area, erupted recently in July 2008 and affected the people of Nikolski some 47 miles away who were stranded for about three weeks. The same eruption also affected the region of Unalaska where flights had to be disrupted frequently.