Homework Tuesday, February 7, 2017 Finish any unfinished work Objective: YWBAT illustrate how the seafloor spreads at mid- ocean ridges and is consumed where it descends into trenches. Drill: When convection takes place in the mantle, why does cooler material sink, while warmer material rises? Homework Finish any unfinished work Plate Tectonics Assessment on Friday

Answer Cooler mantle material sinks because it is more dense than warmer material.

Did you know…? Convection currents circulate material deep inside the Earth in a long, slow movement. A single particle can take hundreds of millions of years to make a complete circle.

Today’s Activities Drill Complete Seafloor Spreading Complete Plate Tectonics DRW Check the last three weeks of drill sheets for accuracy Study for Plate Tectonics WOW Assessment Conclusion

Explain the process of subduction. Closure Explain the process of subduction.

Conclusion Answer A denser oceanic plate is forced beneath a less-dense oceanic or continental plate at a convergent boundary. Gravity pulls the oceanic plate into the asthenosphere, where it begins to melt.