Mount Dana (Alaska) facts for kids
Quick facts for kids Mount Dana |
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Crater of Mount Dana
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| Highest point | |
| Elevation | 1,354 m (4,442 ft) |
| Listing | List of volcanoes in the United States |
| Geography | |
| Location | Alaska Peninsula, United States |
| Geology | |
| Mountain type | Stratovolcano |
| Volcanic arc/belt | Aleutian Arc |
| Last eruption | 1890 BCE (?) |
Mount Dana is a small but interesting stratovolcano located on the Alaska Peninsula in the United States. It sits near Canoe Bay and the top of Pavlof Bay. About 3,840 years ago, Mount Dana had a huge eruption. This eruption sent a fast-moving mix of hot gas and rock, called a pyroclastic flow, down its sides. This flow filled valleys and even reached the sea at Canoe Bay.
What is Mount Dana?
Mount Dana is a type of volcano called a stratovolcano. These volcanoes are cone-shaped and built up over time by many layers of hardened lava, ash, and rocks. Mount Dana is found northeast of the Canoe Bay inlet. It is about 555 miles (893 kilometers) from Anchorage, Alaska's largest city.
The United States has many active volcanoes, especially in Alaska. In fact, about 80% of all volcanoes in the U.S. are in Alaska. This includes those found in the Aleutian Islands. These islands are part of the Pacific Ring of Fire. This is an area around the Pacific Ocean where many earthquakes and volcanic eruptions happen. This is because huge pieces of the Earth's crust, called tectonic plates, are constantly moving and crashing into each other.
How Mount Dana Formed
Mount Dana is made of special volcanic rocks called calc-alkaline rocks. These rocks form from magma (melted rock) deep inside the Earth. The volcano also has parts of an old lava dome made of andesite. A lava dome is a round mound that forms when thick, sticky lava slowly oozes out of a volcano. This dome is located near the western side of Mount Dana's main crater.
The volcano sits on top of older rocks like sandstone and shale. These rocks formed during the Jurassic and Cretaceous periods, which were millions of years ago. Mount Dana rises 1,354 meters (4,442 feet) high. Its top has a large crater that is about 1.5 kilometers (0.9 miles) high and 2 kilometers (1.2 miles) wide. On the southwest side of the volcano, you can see layers of sedimentary rock from the Mesozoic Era. These are rocks formed from bits of older rocks, minerals, or living things that settled and hardened over time.
Mount Dana is easy to reach from Canoe Bay. You can visit it at any time of the year.
When Did Mount Dana Erupt?
There are no written records of Mount Dana erupting in recent history. However, scientists can see signs that it erupted in the past. For example, there is a flow of blocky lava and tephra on the side of the volcano. Blocky lava is a type of lava flow that breaks into rough, jagged chunks as it cools. Tephra is a general term for all the bits of rock, ash, and dust that are thrown into the air during a volcanic eruption. This flow of lava and tephra stretches all the way down to Canoe Bay.
Also, there are cold springs and a very large hill made of tufa near the volcano. Tufa is a type of rock that forms when minerals build up around hot springs. These features suggest that Mount Dana has erupted before, even if we don't have written records of it.
