Chapter 17.1 Outlining Activity Drifting Continets Chapter 17.1 Outlining Activity

Drifting Continents Ch 17. 1 (p. 443) I. Early Observations A Drifting Continents Ch 17.1 (p.443) I. Early Observations A. Ortelius – late 1500’s – noticed apparent fit of continents B. Suess – late 1800’s – southern continents joined – “Gondwanaland” C. Wegener – 1912 – Continental Drift Hypothesis II. Continental Drift A. continents had once been joined as one supercontinent – “Pangaea” 1. 200 mya – Pangaea began to break apart 2. Wegener used more than puzzle-like fit: rock, fossil, climate B. Evidence from Rock Formations 1. Similar rock types should be found on opposite side of the Atlantic 2. Lithology – rock types – match between Appalachians, Europe and Greenland 3. Rocks > 200 mya

C. Evidence from Fossils – similar fossils of plants and animals across continents. 1. Kannemeyerid, Labyrinthodont, and Mesosaurus – could not possibly swim the great distance between continents. 2. Glossopteris – fern that grows in temperate climates indicates that continents were joined and probably near equator

D. Ancient Climate Evidence 1 D. Ancient Climate Evidence 1. Coal beds in Antarctica – coal forms from swamp plants 2. Glacial Deposits – found in Africa, India, Australlia, and South America III. Rejected Hypothesis A. early 1900’s people believed continents were permanent B. Even with evidence his colleagues rejected the hypothesis C. Two major flaws 1. Could not explain what caused the continents to move. 2. No explanation of how continents move across ocean crust D. Wegener died before new evidence in 1960 came along to support his ideas