Education Theme: Seamounts

What is a Seamount?

Fact Sheet. Seamounts rise high off the seafloor, much like mountains do on land, though most are remnants of extinct volcanoes. To be classified as a seamount, the feature must rise at least 1,000 meters (3,300 feet) above the surrounding seafloor.

How Do Seamounts Form?

Fact Sheet. Seamounts are underwater volcanoes found in every ocean. They can form in different ways, but most are remnants of extinct volcanoes. Seamounts are generally found at mid-tectonic plate regions, called hotspots, and near the boundaries of tectonic plates.

Seamounts: Oases of Life

Fact Sheet. Seamounts are hotspots for biodiversity in the deep-sea. They provide a hard substrate for deep-sea organisms to live on and interact with currents driving nutrients up from the seafloor.

Explorations Far Above the Musicians Seamounts

Exploration Note. When NOAA Ocean Exploration explored the Musicians Seamounts, north of the main Hawaiian Islands, they found a high diversity of organisms living on the seamount and in the water column above.

Why Are Seamounts Hotspots for Biodiversity?

Ocean Exploration Fact. With structure for animals to settle and live on and currents supplying food and nutrients, the variety of life, or biodiversity, at seamounts is often rather high.

Geological History of the New England and Corner Rise Seamounts

From the 2021 North Atlantic Stepping Stones expedition. The New England and Corner Rise seamount chains comprise a line of extinct submarine volcanoes that extend from near the Mid-Atlantic Ridge to the eastern continental margin of the United States.

The Monument in Your Backyard

From the 2021 North Atlantic Stepping Stones expedition. Northeast Canyons and Seamounts Marine National Monument Superintendent Brittany Petersen answers questions about this mysterious and fascinating place.

How Did They Get There? Biogeography of Pacific Islands and Seamounts

Marine biogeographers examine the historical, geological, ecological, and environmental factors that influence the distribution of life in the ocean. This research helps to explain why species are found in particular places and not in others.

The Birth, Life, and Death of Pacific Guyot Seamounts

From the 2016 Deepwater Exploration of the Marianas expedition. This essay describes the life cycle of seamounts in the Pacific Ocean in relation to plate tectonics, from birth at a hotspot to death in a subduction zone.

Guyots: Intriguing Flat-topped Seamounts that Host a Diversity of Habitats for Deepwater Animals

From the Deepwater Wonders of Wake expedition. Seamounts that erupt and grow to reach the surface have their conical tops flattened as a result of both erosion and coral reef growth. When these flat-topped seamounts eventually sink back down to deep water, they are called guyots.

Geologic Overview of the West Pacific

From the Deepwater Wonders of Wake expedition. The West Pacific Ocean is underlain by some of the oldest seafloor in the world, and it hosts a large number of submarine volcanoes, referred to as seamounts. These seamounts are typically formed by small extents of melting in the Earth's mantle, which may occur in several different geologic settings. In one of those settings, the so-called hotspots, a chain of volcanoes forms as the Earth's tectonic plates move over areas in the Earth's mantle that are thought to be anomalously hot.

Deep Sea Fauna of the Marianas — Isolated or Connected?

From the Deepwater Wonders of Wake expedition. This mission log explores the large circle of organism distribution and connection among the Mariana region, the Northwest Pacific, the East China Sea, and Japan.

Seamounts: Underwater Islands of the Pacific

From the 2015 Hohonu Moana: Exploring Deep Waters off Hawaiʻi expedition. An overview of seamount age, geology and biological complexity by seamount expert, Dr. Les Watling.