hapten Global Tectonics QurDynamic Planet
Chapter 2: Global Tectonics Our Dynamic Planet
Plate tectonics From Hypothesis to Theory a Plate tectonics is a scientific theory that explains two centuries of often puzzling observations and hypotheses about our planet earth a The continents are drifting very slowly across the face of our planet a Continental drift is a concept with a long history
Plate Tectonics: From Hypothesis to Theory ◼ Plate tectonics is a scientific theory that explains two centuries of often puzzling observations and hypotheses about our planet Earth. ◼ The continents are drifting very slowly across the face of our planet. ◼ Continental drift is a concept with a long history
Plate tectonics From Hypothesis to Theory(2) a century ago geologists puzzled over the fit of the shorelines of africa and south america They noted that fossils of extinct land-bound plants and animals, glacial deposits, and ancient lava flows could be matched together along coastlines that today are thousands of kilometers apart Coal was found in antarctica Coal forms in tropical climates. implying that Antarctica has moved in the past
Plate Tectonics: From Hypothesis to Theory (2) ◼ A century ago geologists puzzled over the fit of the shorelines of Africa and South America. ◼ They noted that fossils of extinct land-bound plants and animals, glacial deposits, and ancient lava flows could be matched together along coastlines that today are thousands of kilometers apart. ◼ Coal was found in Antarctica. ◼ Coal forms in tropical climates, implying that Antarctica has moved in the past
Plate tectonics From Hypothesis to Theory 3) faced with puzzling data, scientist developed hypotheses to explain them Alfred Wegener proposed the most comprehensive early hypothesis for “ Continental drift”in1912
Plate Tectonics: From Hypothesis to Theory (3) ◼ Faced with puzzling data, scientist developed hypotheses to explain them. ◼ Alfred Wegener proposed the most comprehensive early hypothesis for “Continental Drift” in 1912
Plate tectonics From Hypothesis to Theory(4) His theory was widely rejected because: Ocean floor was too strong to be plowed aside Wegener had not proposed a plausible force that could induce the continents to drift ■ Attempts to test Wegener’ s hypothesis with observations had mixed success
Plate Tectonics: From Hypothesis to Theory (4) ◼ His theory was widely rejected because: ◼ Ocean floor was too strong to be plowed aside. ◼ Wegener had not proposed a plausible force that could induce the continents to drift. ◼ Attempts to test Wegener’s hypothesis with observations had mixed success