The Earth’s continents constantly drift around the globe, periodically glomming together and drifting apart. This lesson will serve as an introduction to plate tectonics. Tectonic plates are fragments of the Earth’s crust which are carried around by currents in the mantel – the layer underneath crust. However, in some cases, there is a discrepancy between the speed with which continents drift and the flow of currents underneath. This indicates that these plates are not only being moved by the currents in mantel, but are also pulling themselves. This pulling force also drives convection in the mantel beneath them. Are you interested in observing these changes? Lookout for them on Google Earth and you will find creases where the ocean crust is plunging in.
This video satisfies the 4-ESS2-2 requirement of fourth-grade science proficiency.
Students who demonstrate understanding can: 4-ESS2-2. Analyze and interpret data from maps to describe patterns of Earth’s features.