It is this that fuels a chain of volcanoes, such as the Aleutian Islands, near Alaska. The hypothesis thus predicts that time-progressive chains of volcanoes are developed on the surface. Examples are Yellowstone, which lies at the end of a chain of extinct calderas, which become progressively older to the west. Another example is the Hawaiian archipelago, where islands become progressively older and more deeply eroded to the northwest.
This effort has been vexed by the lack of very long chains, by the fact that many are not time-progressive e. Figure 2. Kilauea is the most active shield volcano in the world. The volcano has erupted nonstop since and it is part of the Hawaiian-Emperor seamount chain. Skip to main content. Plate Tectonics. Search for:.
Reading: Hot Spots Figure 1. As hotspot volcanoes are transported by plate motion away from the mantle plume, hotspot volcanism ceases. Eventually the hotspot volcanoes become extinct, gradually subside, and are eroded by wave action. Over geologic time, these processes produce lines of islands, atolls, and seamounts known as hotspot tracks , or chains.
The youngest, active volcanoes are located within a region of the plate that overlies the mantle plume. Progressively older volcanoes form linear chains on the surface of the moving tectonic plate, downstream of the hotspot. The Hawaiian Islands and the chain of seamounts that continue their trend for about 6, kilometers 3, miles into the northwest Pacific Ocean are an example of a hotspot track.
According to the United States Geologic Survey, there are approximately 1, potentially active volcanoes worldwide. Most are located around the Pacific Ocean in what is commonly called the Ring of Fire.
A volcano is defined as an opening in the Earth's crust through which lava, ash, and gases erupt. The term also includes the cone-shaped landform built by repeated eruptions over time. Teach your students about volcanoes with this collection of engaging material.
Bob Ballard travels to Hawai'i to explore the terrestrial and deep sea geology of the Mauna Kea, the tallest mountain in the world. The Hawaiian Islands were formed by a volcanic hot spot, an upwelling plume of magma, that creates new islands as the Pacific Plate moves over it. Join our community of educators and receive the latest information on National Geographic's resources for you and your students.
Skip to content. Image hot spot eruption on Mount Kilauea. Photograph by the USGS. Twitter Facebook Pinterest Google Classroom. Encyclopedic Entry Vocabulary. Geologists estimate there are about 40 to 50 hot spots around the world. Yellowstone National Park.
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