1. Alfred Wegener

2. Born in Germany 1880 Graduated High School, very interested in Earth Sciences Attended University in Berlin, Germany studied physics, astronomy and meteorology PhD (doctorate degree) in Astronomy Weather balloons to study air masses Three expeditions to Greenland to study polar air circulation

3. Arctic Weather Using kite and balloon launches he pioneered meteorological research, especially on his expeditions to Greenland.

4. first to winter on the inland ice in a hut they built on the ice in Northeast Greenland.

7. Vehicles used to travel

8. Expedition to Greenland in 1929

9. 1930 His last expedition to Arctic Wegener felt responsible for the success of this mission…. During the fourth expedition in 1930, a one-year recording of weather and ice conditions all the way across the inland ice of Greenland, and making use of three stations, had been planned under his leadership.

10. 1930 His last expedition to Arctic The german government had contributed $120,000 ($1.5 million in dollars now) at a time when Germans were starving to death due to post-war shortages. This success depended on enough provisions being transferred from West camp to Eismitte ("mid-ice") for two men to winter there, which was a factor in the decision that led to his death.

11. 1930 His last expedition to Arctic The expedition was ill-fated from the start. Initially, drifting ice delayed unloading of the 98 ton equipment until June of 1930. Subsequently, the motorized propeller sleds, employed for the first time, did not meet expectations; and the remote station ‘Inland Ice’ could not be supplied sufficiently.

12. 1930 His last expedition to Arctic Due to a late thaw, the expedition was six weeks behind schedule, and as summer ended, the men at Eismitte sent a message that they had insufficient fuel, and so would return on October 20. On September 21, 1930 although the route markers were by now largely buried by snow, Wegener set out with thirteen Greenlanders and his meteorologist Fritz Loewe to supply the camp by dog sled. During the journey the temperature reached −76 °F and Loewe's toes became so frostbitten they had to be amputated with a penknife without anaesthetic.

13. 1930 His last expedition to Arctic Twelve of the Greenlanders went back to the West camp. In a letter Wegener writes “that life is now on the line” for his friends at station ‘Inland Ice’. He continues his journey with only two companions and reaches the station on October 30, 1930. After celebrating Alfred Wegener’s 50th birthday at station ‘Inland Ice’ on November 1st, Wegener and his companion Rasmus Villumsen begin their return trip to the western station.

14. 1930 His last expedition to Arctic With only enough supplies for three at Eismitte, Wegener and the other team member took two dog sleds and made back for West camp. They never reached the camp.

15. 1930 His last expedition to Arctic Six months later on May 12, 1931, Wegener's body was found in Greenland, halfway between Eismitte and West camp, buried with great care. A pair of skis marked the grave site. At 50 years of age and a heavy smoker, Wegener's suspected cause of death was heart failure through overexertion. After burying Wegener, the only survivor, Villumsen, departed again for the West camp, but was never seen again. It is estimated that the 23- year-old's body now lies buried under more than 330 ft of accumulated ice and snow.

16. Wegener’s body was reburied in the same spot by the team that found the burial site and marked with a large cross. Ironically, it can be presumed that as the years pass, his body will stray further away from his homeland due to “continental drift”. In an obituary about Alfred Wegener, Hans Benndorf writes: “He was a person of flawless character, unadorned simplicity and rare modesty. At the same time, he was a man of action, who, in pursuing an ideal goal, achieved the extraordinary by means of his iron will power and tenacity while putting his life at risk”.

17. A Remarkable Visionary Wegener was one of the first to realize that an understanding of how the Earth works required input and knowledge from all the earth sciences.

18. Leonardo da Vinci and Francis Bacon wondered about the possibility of the American and African continents having broken apart, based on their shapes. This thinking continued up into the early 20th century, to a meteorologist named Alfred Wegener. Early Observations

19. Alfred Wegener Biography In 1914, as he was recuperting in a military hospital from an injury suffered as a German soldier in World War 1, he developed an idea that had intrigued him for years. He was amazed by the remarkable “fit” of the coastlines of South America and Africa.

20. Wegener sought out many other lines of geologic and ancient earth evidence that these two continents were once joined. During his long convalescence, Wegener was able to fully develop his ideas into the Theory of Continental Drift, detailed in a book published in 1915.

23. Wegener spent much of his life defending his theory of continental drift, which was severely attacked from the start and never gained acceptance in his lifetime. Despite overwhelming criticism from most leading geologists, who regarded him as a mere meteorologist and outsider meddling in their field, Wegener did not back down but worked even harder to strengthen his theory.

24. In his theory of Continental Drift, Wegener stated that all the continents were once joined together in a single landmass called Pangaea and have drifted apart. He was unsure of the cause of the drifting of the continents but suggested centrifugal force of the Earth's rotation, possibly sea floor spreading and the mid ocean ridge had a role…. However, he was not able to prove these thoughts.

25. Continental Drift Ideas of Alfred Wegener Fit of Africa and South America Features common to Africa and South America: – similar rock types and ages – similar plant and animal fossils

26. Permian Glaciation

27. Long swim for Mesosaurus

28. Why they didn’t have to swim or float

29. Wegener’s Downfall: Lack of a Mechanism Support from the southern continents Some acceptance in Europe Almost total skepticism in N.A. Condemnation by American geophysicists. NO MECHANISM!!!

30. Alfred Wegener "Utter rot!" said the president of the prestigious American Philosophical Society. "If we are to believe [this] hypothesis, we must forget everything we have learned in the last 70 years and start all over again," said another American scientist. Anyone who "valued his reputation for scientific sanity" would never dare support such a theory, said a British geologist. Thus did most in the scientific community ridicule the concept that would revolutionize the earth sciences and revile the man who dared to propose it, German meteorological pioneer and polar explorer Alfred Wegener. Science historians compare his story with the tribulations of Galileo.

31. The Wrath of Science The international geological community's reaction to Wegener's theory was militantly hostile. American geologist Frank Taylor had published a similar theory in 1910, but most of his colleagues had simply ignored it. Wegener's more cogent and comprehensive work, however, was impossible to ignore and ignited a firestorm of rage and rancor. Moreover, most of the blistering attacks were aimed at Wegener himself, an outsider who seemed to be attacking the very foundations of geology.

32. BUT Continental Drift and Plate Tectonics Is an Accepted Theory NOW! Why? Is it because scientists suddenly became more open minded? NO!!!!NO!!!!

33. Wegemer’s Continental Drift and the Theory of Plate Tectonics Is Accepted Today because….. new evidence emerged which strongly supports his theory. believable mechanismThere is now a believable mechanism for the way in which the continents drift.

34. New Evidence to Support Plate Tectonics

35. Paleomagnetism and the Revival of Continental Drift Nature of Paleomagnetism Magnetism is a property of a material that contains iron. In molten rock..that has not yet cooled, the magnetic grains will align parallel to earth’s magnetic field and then cools to become a solid “record” showing the position of earth’s magnetic poles.

36. Preservation in rocks of the orientation of the magnetic field

37. Paleomagnetism, etc. Results of Paleomagnetic Studies Plotting position of pole based on North American data shows an apparent wandering through time. 13,000 MILES TO PRESENT POSITION IN ARCTIC CIRCLE.

38. Paleomagnetism Results However, the position of the pole from European data does not match that of the data from North America. Indeed, each continent appears to have its own path for polar wandering. Because this is impossible, continents must have been moving about during this time. Only recently have they moved to the present position.

39. Evidence from the Oceans World War II brought a spectacular advance in our abilities to study the ocean. Among the discoveries were: –Heat-flow measurements –Thickness of the oceanic crust –Thickness and age of sedimentary deposits on the ocean floor. –Earthquakes along ridges, trenches. –Very large fractures, most of them faults.

40. Exploring the Ocean Floor

41. Hypothesis of Sea-Floor Spreading Convection currents in mantle rise under oceanic ridges and spread. Driving force is here transferred from core to mantle. Oceanic crust (basaltic) created at ridges. Crust plus upper mantle (lithosphere) move laterally away – going along for the ride.

42. Hypothesis of Sea-Floor Spreading

43. Sea-Floor Spreading Lithosphere plunges into oceanic trenches. Does this explain the anomalies of ocean floor heat distribution? Continents don’t drift through the mantle but are passengers. Oceanic crust has to be young because older rocks have been: –Plastered onto the edge of continents. –Thrust down into the mantle. Why are the sedimentary materials on the ocean floor so thin?

44. Confirmation of Sea-Floor Spreading Earth’s magnetic field periodically reversed. The age of these reversals determined by radiometric dating. Magnetic anomalies found on both sides of oceanic ridges. Preserved in basalt formed in center of rise.

45. Magnetic anomalies

46. Confirmation of Sea-Floor Spreading

47. Through sea-floor spreading, sea floor has served as a tape recorder – working in stereo. Preserved record of reversals and their time of occurrence. Can also determine rate of spreading. ~ 1 inch per year in North Atlantic ~ 2 inches per year in South Pacific

48. Plate Tectonics Basics Earth’s lithosphere broken into large plates. Upwelling of magma creates new oceanic crust. Added to edge of plate. Plates diverge from ridge. Elsewhere, plates – Pass into oceanic trenches (subduction). –Collide with each other. –Push past each other along great strike-slip faults.

49. Plate Boundaries

50. Convergent Plate Boundaries

51. Plate Tectonics Collisions can involve an oceanic plate and a continental plate, two continental plates, or two oceanic plates. Continents do not drift, but are rafted about. Some oceanic basins are steadily widening; others are closing. Driving mechanism believed to be convection currents of some type.

52. Hypotheses About Convection Cells

53. Plate Tectonics Benioff zones: long narrow earthquake zones dipping into the lithosphere. Created by rupture of subducting plate. Hot spots where plumes of magma rise from the asthenosphere. –Remain fixed –Plate migrates over, creating chain of volcanoes. Hawaii, Yellowstone

54. Continental Rifting

56. Vindication Some of the earliest evidence confirming Wegener's theories of continental drift was revealed when geologists measured the age of the ocean floor. Crustal rocks near the mid-ocean ridges are always very young, while the ocean crust along continental margins, furthest away from the ridges, is hundreds of millions of years older. New ocean floor is being created at the mid-ocean ridges—pushing the continents along