Sea Floor Spreading Evidence For Continental Drift
Plates are composed of lithosphere about 100 km thick that float on the ductile asthenosphere.
Sea floor spreading evidence for continental drift. By the 1960s the theories of continental drift and sea floor spreading were supported by reliable scientific data and combined to develop modern day plate tectonic theory. Seafloor spreading disproves an early part of the theory of continental drift. This evidence however was also used to support the theory of continental drift. The theory maintains that the crust and uppermost mantle or lithosphere is segmented into a number of solid rigid slabs called lithospheric plates.
The existence of mid ocean ridges where seafloor spreading starts b. Whats people lookup in this blog. In 1965 a canadian geophysicist j. Evidence of similar paleoclimates in belts across pangaean latitudes.
This evidence was from the investigations of the molten material seafloor drilling radiometric age dating and fossil ages and the magnetic stripes. Seafloor spreading proves that the ocean itself is a site of tectonic activity. How did seafloor spreading provide evidence for continental drift. In 1963 fred vine and d h.
Seafloor spreading evidence for continental drift. These plates float atop an underlying rock layer called the asthenosphere. By combining the sea floor spreading theory with continental drift and information on global seismicity the new theory of plate tectonics became a coherent theory to explain crustal movements. Matthews used paleomagnetism to test the theory of seafloor spreading by studying paleomagnetic data from a portion of the midocean ridge system if the seafloor has spread laterally by the addition of new crust at the oceanic ridges there should be a relatively symmetrical pattern of magnetic orientation normal polarity reversed polarity normal polarity and.
Studies conducted with thermal probes for example indicate that the heat flow through bottom sediments is generally comparable to that through the continents except over the mid ocean ridges. Plate tectonics theory convection currents and sea floor spreading. The matching of the distribution of similar fossils across oceans. Tuzo said that earth s crust or lithosphere was divided into large rigid pieces called plates.
Tuzo wilson combined the continental drift and seafloor spreading hypotheses to propose the theory of plate tectonics. Which of the following lines of evidence for continental drift plate tectonics was found after wegener published his theory. Alfred wegener a german meteorologist born in 1880 developed the idea of continental drift. Harry hess s hypothesis about seafloor spreading had collected several pieces of evidence to support the theory.
Supporters of continental drift originally theorized that the continents moved drifted through unmoving oceans. He suggested that continents moved around the earth like giant rafts.