Which of the following statements are correct with reference to the Circum-Pacific Belt?

A. The Circum-Pacific Belt accounts for about 80% of the active volcanoes in the world.
B. This belt is also called the 'Fire Girdle' of the Pacific Ocean.
C. Here, volcanoes are primarily caused by the collision of convergent plates along the Benioff zones.
D. This zone is also known for divergent plate margins.

Choose the most appropriate answer from the options given below:

Correct option is A

B. This belt is also called the 'Fire Girdle' of the Pacific Ocean. This is also correct. The region is frequently referred to as the 'Ring of Fire' or the 'Fire Girdle' because of its high level of volcanic and seismic activity around the Pacific Ocean basin.

C. Here, volcanoes are primarily caused by the collision of convergent plates along the Benioff zones. This statement is correct. The Benioff zones are areas where one tectonic plate is forced under another (subduction zones), leading to volcanic activity.

Information Booster:

The Circum-Pacific Belt, also known as the Ring of Fire, is a geologically active region that encircles the Pacific Ocean, extending through the coastlines of the Americas, Asia, and Oceania. This area is characterized by high levels of volcanic activity and earthquakes, making it one of the most seismically active regions on Earth. The concept of the Circum-Pacific Belt involves understanding the tectonic interactions that drive these phenomena.

1. Tectonic Plate Interactions:
   The primary reason for the geologic activity in the Circum-Pacific Belt is the presence of convergent plate boundaries, where tectonic plates collide, and one is forced beneath another in a process called subduction. At these convergent boundaries, oceanic plates are usually subducted beneath continental plates because oceanic plates are denser. As the oceanic plate descends into the mantle, it melts, and the magma rises to the surface, forming volcanoes.

   The Benioff zone is a seismic zone formed along these subduction boundaries, where the descending plate causes deep-focus earthquakes. The subduction zones along the Circum-Pacific Belt create not only volcanoes but also deep earthquake activity, which further contributes to the region’s geologic volatility.

2. Volcanic Arcs and Earthquakes:
   The volcanic activity in the Circum-Pacific Belt is mainly due to the subduction of oceanic plates. As the oceanic crust subducts beneath continental or other oceanic plates, the pressure and heat cause it to melt and form magma. This magma, being less dense than the surrounding rock, rises to the Earth's surface, forming volcanic arcs. These arcs are typically located at convergent boundaries and form chains of volcanoes, which are part of the "Ring of Fire."

   This volcanic activity is not limited to oceanic plates; in some cases, when one oceanic plate subducts beneath another oceanic plate, a series of volcanic islands can form. One of the most prominent examples of this phenomenon is the Japanese Archipelago.

3. Earthquake Activity:
   The subduction process in the Circum-Pacific Belt generates significant seismic activity. The descending plates create immense pressure, leading to earthquakes that can be shallow, intermediate, or deep in nature. These earthquakes are primarily concentrated in Benioff zones (named after seismologist Hugo Benioff), which refer to areas where earthquakes are associated with the subduction of oceanic plates.

   Earthquakes along the Ring of Fire are often accompanied by tsunamis—large ocean waves caused by the sudden displacement of water during undersea earthquakes.

4. Divergent Boundaries in the Context of the Ring of Fire:
   While the Circum-Pacific Belt is mostly associated with convergent plate boundaries (where plates move toward each other), divergent plate boundaries, where plates move apart, also exist but play a lesser role. Divergent plate boundaries are most commonly found in the Mid-Atlantic Ridge and East African Rift but are not as prevalent in the Ring of Fire. These divergent boundaries, where new oceanic crust is formed as plates separate, are distinct from the subduction zones of the Circum-Pacific Belt.

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