How do each of the three types of magma originate in terms of melting mechanism and part of the earth where they form?

1) Basaltic magma

2)Andesitic magma

3)Rhyolitic magma

Explanation:

1) Basaltic magma:

Basaltic magma is formed through dry partial melting of the mantle. The mantle lies just below the crust of the earth. Basalts make up most of the ocean’s crust; this is why basaltic magma is typically found in oceanic volcanoes.

2)Rhyolitic magma

Rhyolitic magma forms as a result of wet melting of continental crust. Rhyolites are rocks that contain water and minerals that contain water, such as biotite. The continental crust must be heated above the normal geothermal gradient in order to melt. The most common cause of a rise in temperature of continental crust is basaltic magma rising from the mantle.

3)Andesitic magma

Andesitic magma is formed through wet partial melting of the mantle. The mantle under the ocean has contact with water. When subduction, or continental plates pulling away from one another, occurs, the mantle will heat up and water is pushed into it. This causes the melting temperature of the mantle to decrease, causing the mantle to begin partially melting due to the heat.