Volcanoes usually occur at fault lines. Fault lines are where tectonic plates push together, pull apart and slide past each other. The energy created here forms volcanoes and causes eruptions. This isnt the only way volcanoes form though. Some volcanoes, like those found in Hawaii, occur over hot spots. Hot spots are portions of the mantle at which the temperature is abnormally high. These high temperatures cause magma to rise and break through Earths crust. This type of volcano often forms a seamount. A seamount is an undersea mountain that becomes an island if it surpasses sea level. While a seamount is over a hot spot, it remains volcanically active. But over the course of millions of years, as tectonic plates shift and the seamount moves, the volcano eventually becomes extinct.When is a seamount volcanically active?

VOLCANOES

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Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]

Volcanoes usually occur at fault lines. Fault lines are where tectonic plates push together, pull apart and slide past each other. The energy created here forms volcanoes and causes eruptions. This isn’t the only way volcanoes form though. Some volcanoes, like those found in Hawaii, occur over hot spots. Hot spots are portions of the mantle at which the temperature is abnormally high. These high temperatures cause magma to rise and break through Earth’s crust. This type of volcano often forms a seamount. A seamount is an undersea mountain that becomes an island if it surpasses sea level. While a seamount is over a hot spot, it remains volcanically active. But over the course of millions of years, as tectonic plates shift and the seamount moves, the volcano eventually becomes extinct.When is a seamount volcanically active?

A	while it is over a hot spot
B	when it surpasses sea level
C	when it occurs at a fault line
D	when tectonic plates move it

Explanation:

Detailed explanation-1: -Sixty percent of all active volcanoes occur at the boundaries between tectonic plates. Most volcanoes are found along a belt, called the “Ring of Fire” that encircles the Pacific Ocean. Some volcanoes, like those that form the Hawaiian Islands, occur in the interior of plates at areas called “hot spots.”

Detailed explanation-2: -Deep within the Earth it is so hot that some rocks slowly melt and become a thick flowing substance called magma. Since it is lighter than the solid rock around it, magma rises and collects in magma chambers. Eventually, some of the magma pushes through vents and fissures to the Earth’s surface.

Detailed explanation-3: -Volcanoes are most common in these geologically active boundaries. The two types of plate boundaries that are most likely to produce volcanic activity are divergent plate boundaries and convergent plate boundaries.

Detailed explanation-4: -Constructive plate boundary volcanoes At constructive plate boundaries, the tectonic plates are moving away from one another. The Earth’s crust is pulled apart to create a new pathway for rising hot magma to flow on to the surface. Volcanoes can sometimes form in these setting; one example is Iceland.

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GEOLOGY

EARTH SCIENCE

VOLCANOES