What is the cause of volcanic activity in new zealand?

Explanation:

New Zealand is located in one of the most tectonically active regions of the world, the pacific ring of fire.

Volcanic activities is produced from uprising magma through the earth. They usually occur around plate boundaries on the surface of the earth.

New Zealand sits around an area where the Pacific plate subducts under the Indo-Australian plate. As the subduction occurs, the rocks beneath undergoes partial melting leading to the formation of magma. The magma reaches the surface in landward regions away from the subduction margins and series of volcanic arcs can form. These series of volcanoes typifies the tectonic setting of New Zealand and it is responsible for the vast volcanic activity in the region.