Seafloor Spreading and Plate Tectonics (Part 2)
Geophysicist and geologist Tanya Atwater talks about the Deep Sea Drilling Project and the confirmation of magnetic reversals that provided strong evidence of seafloor spreading and plate tectonics.
Plate Tectonics and Earthquake Distribution
Geophysicist and geologist Tanya Atwater talks about the correlation between plate boundaries and earthquake distribution.
Oceanic Crust vs. Continental Crust
Geophysicist and geologist Tanya Atwater discusses the differences between continental and oceanic crust. Continental crust tends to be much thicker and would be thicker still were it not for the forces of gravity and erosion. In addition, oceanic c...
Plate Tectonics and Heat
Geophysicist and geologist Tanya Atwater talks about plate tectonics as a mechanism by which Earth's interior sheds the tremendous heat that builds up as a result of radioactive decay.
Pangaea
Geophysicist and geologist Tanya Atwater talks about the super continent Pangaea, thought to have broken up into the continents as we know them today beginning about 200 million years ago.
Alfred Wegener and Continental Drift
Geophysicist and geologist Tanya Atwater discusses the role of Alfred Wegener in bringing together a variety of evidence in support of the theory of continental drift.
Isostasy
Geophysicist and geologist Tanya Atwater discusses isostasy, which allows objects at the surface of Earth to float in equilibrium, and talks about how it helps define Earth's topography.
Differences Between Oceans and Continents (Part 2)
Geophysicist and geologist Tanya Atwater compares the relatively neat sea floor with continents, which she terms a "mess." She attributes these differences to the predictable and "tidy" process of seafloor spreading, as compared to the crashing toge...
Coasts Are Arbitrary
Geophysicist and geologist Tanya Atwater notes that the line between oceans and continents, commonly known as the coast, is actually very arbitrary and subject to change over time. She also talks about implications of global warming for coastal regi...
Making the Pieces Fit: Seafloor Spreading
Alfred Wegener's hypothesis was rejected by many who felt it lacked a credible mechanism which could explain the continental movement hypothesized by Wegener. The notion of seafloor spreading, which suggested that new seafloor develops at oceanic ri...