How is a spreading plate boundary different from a sliding plate boundary?

Usually, a sliding plate boundary(conservative boundary) causes earthquakes, while spreading plate boundaries(constructive) usually cause shield volcanoes.

Earth's outer layer, the crust, is divided into a set of large moving plates. The lines where they meet are called plate boundaries.

Master planned communities outside of chicago. note: population density means people living in an area per square mile. chicago, an urban and highly populated area has a much more higher density than a desert, amish community, settlement, or nomadic region.