theory of continental drift the present is the key to the past
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Theory of Theory of Continental DriftContinental Drift
The Present is the Key to the The Present is the Key to the PastPast
James Hutton 1785 James Hutton 1785 UniformitarianismUniformitarianism
Known as the father of geology
UniformitarianismUniformitarianism
The present is the key to the pastThe present is the key to the past The geological forces and processes The geological forces and processes
of today are the same as those from of today are the same as those from the past.the past.
These forces are very slow and These forces are very slow and methodical.methodical.
Evidence for continental Evidence for continental driftdrift
Matching Coastlines(jigsaw puzzle)
Becomes more of a match when you use the continental shelves.
Evidence for continental Evidence for continental driftdrift
Matchingfolded mountainRanges(Atlas, Appalachians, and Scandinavian Highlands)
Evidence for continental Evidence for continental driftdrift
Salt beds found in Texas and Germany. Salt beds found in Texas and Germany. These are only created in dry tropical areas.These are only created in dry tropical areas.
Evidence for continental Evidence for continental driftdrift Coal deposits found in USA. Coal is Coal deposits found in USA. Coal is
created in environments similar to created in environments similar to the Everglades.the Everglades.
Evidence for continental Evidence for continental driftdrift
Matching coastlinesMatching coastlines Matching folded mountainsMatching folded mountains Matching glacier depositsMatching glacier deposits Salt beds in Texas and GermanySalt beds in Texas and Germany Coal beds in West Virginia Coal beds in West Virginia Matching fossilsMatching fossils
PangaeaPangaea
A Greek word meaning “All-lands” A Greek word meaning “All-lands” Split apart approximately 200 MYBPSplit apart approximately 200 MYBP
Continental driftContinental drift
Theory that continents drift on the Theory that continents drift on the surface of the Earthsurface of the Earth
No mechanism proposedNo mechanism proposed No one believed this was possibleNo one believed this was possible
Glomar ChallengerGlomar Challenger
1960’s this ship took core samples of 1960’s this ship took core samples of ocean floor rocks as it crossed the ocean floor rocks as it crossed the Atlantic OceanAtlantic Ocean
A map was produced from this data A map was produced from this data showing the rock types and agesshowing the rock types and ages
From this map a new theory was From this map a new theory was developed to explain Wegener’s developed to explain Wegener’s evidenceevidence
Ocean floor rock agesOcean floor rock ages
Get older symmetrically away from Get older symmetrically away from ridges, the oldest rocks have to be ridges, the oldest rocks have to be 200,000,000 years old200,000,000 years old
Theory: sea floor splits apart and Theory: sea floor splits apart and rocks move away from each otherrocks move away from each other
Process: Seafloor spreadingProcess: Seafloor spreading Seafloor spreading provides clues to Seafloor spreading provides clues to
mechanism driving continental driftmechanism driving continental drift
Does sea floor spreading explain Does sea floor spreading explain everything ?everything ?
If the Atlantic Ocean is spreading, If the Atlantic Ocean is spreading, doesn’t that mean some place is doesn’t that mean some place is being squeezed togetherbeing squeezed together
Plate TectonicsPlate Tectonics
Combining Hutton theory, Combining Hutton theory, Wegener’s evidence, Glomar Wegener’s evidence, Glomar Challenger’s data, and the following Challenger’s data, and the following world map the present theory of world map the present theory of Plate Tectonics came into beingPlate Tectonics came into being