What are some characteristics of a. shield volcanoes b. composite volcanoes in terms of their base/slope/height, in their nature of eruption?
The size of shield volcanoes is enormous and their structure is formed by multiple flowing lava layers. Since the basaltic lava that is poured out is fluid the resulting cone has not a sharp slope.
The hot spots, found in oceanic lithosphere or in mantle, may cause the shield volcanoes, having an eruption of lava that is not explosive. The vent of shield volcanoes is characterized by sharp conical hills and sharp cones of lava fragments.