Tectonics vocab #1-10

Front

Folded mountains & ocean trenches form at a _____________ boundary where plates converge.

Back

convergent

Front

Iceland is growing larger due to the mid-ocean ridge, a __________ boundary that is spreading apart.

Back

divergent

Front

Harry Hess proposed the theory of _______________________ in the 1960s to explain underwater mountain ranges called mid-ocean ridges.

Back

Seafloor spreading

Front

Tectonic plates move on a thick, plastic-like layer of the mantle, like a raft on water. This layer is the _______________________.

Back

asthenosphere

Front

Outermost layer of Earth’s plates, ~100 km thick, made of oceanic & continental crust, and upper mantle is called _____________.

Back

lithosphere

Front

Hot, dense center of Earth made of solid iron (inner) & liquid metal (outer) is called the ____________.

Back

core

Front

Sections of Earth’s crust & upper mantle float & move like rafts on a plastic-like layer.

Back

plates

Front

Theory combining findings from two theories; Earth's crust & upper mantle are divided into sections floating on a plastic-like mantle layer.

Back

Plate tectonics

Front

____________ means 'all land' and refers to the supercontinent Wegener believed split apart 200 million years ago.

Back

Pangaea

Front

Alfred Wegener's hypothesis that continents were once joined and moved apart is called _____________.

Back

Continental drift