In marine geology, a guyot, also known as a tablemount, is an isolated underwater volcanic mountain (seamount) with a flat top more than 200 m (660 ft) below the surface of the sea. The diameters of these flat summits can exceed 10 km (6.2 mi). Guyots are most commonly found in the Pacific Ocean, but they have been identified in all the oceans except the Arctic Ocean.
A seamount is a large geologic landform that rises from the ocean floor but that does not reach to the water's surface, and thus is not an island, islet or cliff-rock. Seamounts are typically formed from extinct volcanoes that rise abruptly and are usually found rising from the seafloor to 1,000–4,000 m (3,300–13,100 ft) in height. They are defined by oceanographers as independent features that rise to at least 1,000 m (3,281 ft) above the seafloor, characteristically of conical form. The peaks are often found hundreds to thousands of meters below the surface, and are therefore considered to be within the deep sea. During their evolution over geologic time, the largest seamounts may reach the sea surface where wave action erodes the summit to form a flat surface. After they have subsided and sunk below the sea surface such flat-top seamounts are called "guyots" or "tablemounts".
In geology, the places known as hotspots or hot spots are volcanic regions thought to be fed by underlying mantle that is anomalously hot compared with the surrounding mantle. Examples include the Hawaii, Iceland and Yellowstone hotspots. A hotspot's position on the Earth's surface is independent of tectonic plate boundaries, and so hotspots may create a chain of volcanoes as the plates move above them.
The geology of the Pacific Northwest includes the composition, structure, physical properties and the processes that shape the Pacific Northwest region of North America. The region is part of the Ring of Fire: the subduction of the Pacific and Farallon Plates under the North American Plate is responsible for many of the area's scenic features as well as some of its hazards, such as volcanoes, earthquakes, and landslides.
The Bowie hotspot is a volcanic hotspot, located 180 kilometres (110 mi) west of the Queen Charlotte Islands in the Pacific Ocean.
Bowie Seamount is a large submarine volcano in the northeastern Pacific Ocean, located 180 km (110 mi) west of Haida Gwaii, British Columbia, Canada.
The Tuzo Wilson Seamounts, also called J. Tuzo Wilson Knolls and Tuzo Wilson Knolls, are two young active submarine volcanoes off the coast of British Columbia, Canada, located 200 km (124 mi) northwest of Vancouver Island and south of the Haida Gwaii archipelago The two seamounts are members of the Kodiak-Bowie Seamount chain, rising 500 m (1,640 ft) to 700 m (2,297 ft) above the mean level of the northeastern Pacific Ocean and is a seismically active site southwest of the southern end of the Queen Charlotte Fault. They are named after Canadian geologist John Tuzo Wilson.
The Kodiak–Bowie Seamount chain, also called the Pratt–Welker Seamount chain and the Kodiak Seamounts is a seamount chain in the southeastern Gulf of Alaska stretching from the Aleutian Trench in the north to Bowie Seamount, the youngest volcano in the chain, which lies 180 km (112 mi) west of the Queen Charlotte Islands, British Columbia, Canada. The oldest volcano in the chain is the Kodiak Seamount. Although the Kodiak Seamount is the oldest extant seamount in the Kodiak-Bowie chain, the adjacent lower slope contains transverse scars indicating earlier subduction of seamounts.
Hodgkins Seamount is a seamount in the Kodiak-Bowie Seamount chain, located south of Pierce Seamount and north of Bowie Seamount. It has apparently experienced two generically different episodes of volcanism, separated by about 12 million years. Like the rest of the Kodiak-Bowie seamounts, it was formed by the Bowie hotspot.
The Explorer Seamount is a seamount located in the Pacific Ocean off the coast of British Columbia, Canada. It is on the Explorer Ridge, a tectonic spreading centre that separates the Pacific and Explorer plates and so the volcanism is rift-related. It is the namesake of the Explorer Ridge.
The Oshawa Seamount is a seamount located in the Pacific Ocean off the coast of Haida Gwaii, British Columbia, Canada.
The Dellwood Seamounts are a seamount range located in the Pacific Ocean northwest of Vancouver Island, British Columbia, Canada. They are also known as the Dellwood Seamount Range or the Dellwood Seamount Chain.
The Tucker Seamount is a seamount located in the Pacific Ocean off the coast of northern Vancouver Island, British Columbia, Canada.
The Chelan Seamount is a seamount located in the Pacific Ocean off the coast of northern Vancouver Island, British Columbia, Canada.
The Seminole Seamount is a seamount located in the Pacific Ocean off the coast of northern Vancouver Island, British Columbia, Canada.
The Union Seamount is a seamount located in the Pacific Ocean off the coast of northern Vancouver Island, British Columbia, Canada.
The Union Seamount is a seamount located in the Pacific Ocean off the coast of northern Vancouver Island, British Columbia, Canada.
The Heck Seamount is a seamount located in the Pacific Ocean off the coast of central Vancouver Island, British Columbia, Canada.
The Newfoundland Seamounts are a group of seamounts offshore of Eastern Canada in the northern Atlantic Ocean. Named for the island of Newfoundland, this group of seamounts formed during the Cretaceous period and are poorly studied.
