What is the volcano type that is very large and broad and has gently sloping sides formed from low viscosity lava

The volcano that is very large and broad and has gently sloping sides formed from low viscosity lava is recognized as a 'Shield Volcano'.

Explanation:

They volcanoes are broadly classified into four main types, viz. Cinder Volcanoes, Composite Volcanoes, Shield Volcanoes, and Lava Domes. Out of these four, the Shield Volcanoes are the largest in size and span. The low viscosity of the lava that comes out of Shield Volcanoes is due to the presence of high amount of molten basalt in the lava.

A very large and broad volcano that has gently sloping sides is known as a shield.