Mid-oceanic ridges are zones of crustal creation, while subduction zones mark the destruction of oceanic crust. In this context, explain how seafloor spreading and subduction collectively support the Plate Tectonics Theory.

Answer: 

Approach to the answer: 

Comprehending and organizing the response:  The question is divided into two sections: definition of sea floor spreading and notable proof of sea floor spreading. For improved presentation, include a seafloor spreading diagram as well.

Introduce yourself and briefly describe the sea floor spreading process. 

• In the 1960s, Professor Harry Hess put forth the theory of sea floor spreading. Numerous facts that were used as key evidence in favor of the SeaFloor Spreading theory were discovered during the 1940s and 1950s through mapping of the ocean floor and paleomagnetic studies of rocks from oceanic regions.

Body: Sketch a seafloor spreading diagram.  

• The oceanic crust is ruptured by the frequent volcanic eruptions brought on by upwelling magma at the mid-oceanic ridges. The oceanic crust on either side is pushed as the fresh lava wedges into it. Seafloor spreading is the name given to this process. Subduction zones, where oceanic crust slides beneath continents or other oceanic plates and sinks back into the mantle, also destroy the seafloor.

Strong Supporting Evidence: List all of the supporting evidence in point form. 

In conclusion, emphasize the significance of the SeaFloor Spreading theory. and discuss how additional study can contribute to a deeper comprehension of the idea of seafloor spreading.

• While the quake foci in the mid-oceanic ridge areas have shallow depths, the deep trenches have deep-seated earthquake occurrences. This indicates that the rocks on the ocean floor’s surface are moved by lava upwelling. The ocean floor is also compelled to enlarge. 
• Wegener’s Continental Drift theory was superseded by the SeaFloor Spreading theory. It cleared the path for the creation of fresh hypotheses to explain the distribution of oceans and continents, such as plate tectonic theory.

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Practice Question:

Question: “Seafloor spreading not only explains the formation of oceanic crust but also helps understand major geological phenomena such as oceanic trenches, volcanic arcs, and island chains.” Elaborate. (250 words)

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