Comment: 18:24 - 19:31 (01:07)
Source: Annenberg/CPB Resources - Earth Revealed - 5. The Birth of a Theory
Keywords: "J. Tuzo Wilson", "Lynn Sykes", earthquake, fault, "mid-oceanic ridge", "sea floor spreading", "mid-Atlantic ridge", "transform fault"
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Our transcription: A further test of the sea floor spreading hypothesis was carried out by Geophysicists J. Tuzo Wilson and Lynn Sykes.
They were interested in the faulting which offsets mid-ocean ridges.
If a feature such as a road or a fence is split and moved by an earthquake, one can deduce how the crust shifted along the fault by measuring the direction of movement and the amount of offset.
Many scientists expected the same to hold true with faults cutting across the mid-ocean ridges, but Wilson and Sykes pointed out that if new crust is forming at ridges, then growing sea floor should shift along the faults in the opposite direction.
Based on his study of seismic records from the mid-Atlantic ridge, Sykes concluded that this, in fact, was taking place.
Wilson and Sykes named the new class of geologic structure "transform faults," which served as further proof of sea floor spreading.
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Geology School Keywords
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