The development of modern plate tectonics was one of the major scientific achiev
ID: 295637 • Letter: T
Question
The development of modern plate tectonics was one of the major scientific achievements attributed to geological oceanography. Plate tectonics reveals the physical processes responsible for the topographical features present on our planet as well as provides insight into future occurrences of tectonic activity and the associated impacts. The evolution from “Continental Drift” to current plate tectonic theory is historically rich but can, at times, be somewhat confusing due to its length and complexity.
List the main developments in chronological order leading up to the theory of plate tectonics.
Which one do think was the most influential in the acceptance of modern plate tectonics and why?
Suggest a discussion topic for this unit (Geological Oceanography). Please be specific. Explain why this topic would be well suited to a discussion format.
Explanation / Answer
Major developments that led to the theory of plate tectonics were:
- The theory of continental drift was explained in a book written by a German scientist named Alfred Wegener in 1915, based largely on the idea of the breakup of a supercontinent Pangaea.
- During 1937, another book by a South African scientist Alexander du Toit documented ample evidence such as the presence of similar fossils on either side of the Atlantic Ocean, similar paleoclimatic signatures in strata, similar landmass configuration of Africa and South America that supported the hypothesis of continental drift
- By the end of the 1950s, there was another evidence in the form of paleomagnetic signatures from the ocean floor basalts which showed that the magnetic field of the Earth underwent contrasting fluctuations over geological timescales.
- During the mid-1960s, it was realized that despite the lack of explanation for crustal movements, the theory of continental drift could be used as a guide to developing a new theory which came to be known as the Plate Tectonic Theory.
- By the end of the 1960s, the major plates were defined with clear explanations as to why such tectonic plates on the Earth's surface move relative to each other.
The acceptance of modern plate tectonic theory was mainly influenced by the results obtained from the seafloor basalts. It was found that the oceanic crust has been moving over millions of years and that its movement has been a part of a tectonic cycle which involved a series of processes leading to the destruction of old rocks and formation of new rocks.
In the context of Geological Oceanography, a discussion can be done on a topic pertaining to Ophiolites. Several views can be shared as to why the ophiolitic sequences are found on the continents and how such sequences are well-preserved underneath the oceanic crust. This topic has several ideas linked to the theory of Plate Tectonics which would be effectively understood with a discussion.