GEOLOGY

Detailed explanation-1: -The vast majority of volcanic activity on the planet occurs along the mid-ocean ridge, and it is the place where the crust of the Earth is born. The material that erupts at spreading centers along the mid-ocean ridge is primarily basalt, the most common rock on Earth.

Detailed explanation-2: -Basaltic lavas erupt mostly from fissures, or cracks, in the seafloor. Ninety percent of the Earth’s eruptive activity and heat loss from the interior takes place along the mid-ocean ridge system.

Detailed explanation-3: -Constructive plate boundary volcanoes Iceland lies on the Mid Atlantic Ridge, a constructive plate boundary, where the North American and Eurasian plates are moving away from each other. As the plates pull apart, molten rock (magma) rises up and erupts as lava, creating new ocean crust.

Detailed explanation-4: -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-5: -The lava produced at the spreading centers is basalt, and is usually abbreviated MORB (for Mid-Ocean Ridge Basalt). MORB is by far the most common rock type on the Earth’s surface, as the entire ocean floor consists of it.