3 Continental drift – idea that continents have moved slowly to their current positions due to convection currents in the mantel.Pangea – the idea that the all land masses on earth were once a single large land mass.
4 Ocean floor spreading – theory that hot less dense material below Earth’s crust rises toward the surface at the mid-ocean ridges. Then, it flows sideways, carrying the seafloor away from the ridge in both directions.Convection current – unequal distribution of heat in the mantel causes a net movement in a circular motion.
6 The Earth’s CRUST is the outer most part of the Earth’s surface. Average 32 km thickThickest point 70 km (in mountains)Thinnest point 8 km (under ocean)
7 Plate tectonic – theory that Earth’s crust and part of the upper mantle are broken into sections called plates.Lithosphere – all of the earth’s crust and part of the upper mantle.Asthenosphere – plastic like layer below the lithosphere. The ridged plates of the lithosphere “float” on the more plastic layer called the asthenosphere.
10 Deformation – The breaking, tilting, and folding of crustal rock due to crustal movement. (three types of forces)Compression – squeezing of earth’s crust that compacts the rock. Convergent boundary2. Tension – is the pulling apart of the earth’s crust. Divergent boundary.3. Shearing – pushes rocks side by side in opposite directions. Transform boundary.