DARIOUS J

HARRY HAMYMOND HESS

• 1906- Hess was born
• In 1959 he presented his sea floor spreading hypothesis
• In 1962 these ideas were published in history of ocean basins
• In 1962 Hess was appointed chair man of the space science board of the national academy of science
• In 1969 Hess died

ABRAHAM ORTEIUS

• In 1596 ortelius suggested that the continents were once joined
• Ortelius said that earthquakes and floods split the continets up

ALFRED WEGNER

• In 1912 Alfred Wagner set his theory of continental drift
• In 1915 Wagner theory was published in a book
• In 1930 Wegner died
• In 1950 his thory develop a new theory of plate tectonics

DEFINITIONS

• Sea floor spreading a process which new molten material from earth has formed–Hess
• Mid ocean ridges- mountain ranges in the ocean from sea floor spreading-ortelius
• Continental drift- the movement of continents -Wegner
• Pangea- a land mass that existed when all continents were joined -Wegner
• Plate tectonics- theory of global tectonics,that move around, collide, or slide with others- Wegner