Final answer:
The theory of plate tectonics was developed through the accumulation of evidence and testing of hypotheses. Alfred Wegener's proposal of continental drift and Harry Hess's theory of sea floor spreading provided key components of the theory. Further evidence, such as earthquake mapping and volcano distribution, confirmed the idea.
Step-by-step explanation:
The theory of plate tectonics was developed using the process of science through the accumulation of evidence and the testing of hypotheses. It started with the proposal of continental drift by Alfred Wegener in the early 20th century, which was supported by evidence such as the fit of continents, matching fossils, and rock formations across different continents. However, it was not widely accepted at the time due to the lack of a mechanism to explain the movement of continents.
In the 1960s, new evidence from the exploration of the ocean floor, particularly the discovery of mid-ocean ridges and magnetic striping, led to the development of the theory of sea floor spreading by Harry Hess. This provided a mechanism for continental drift, as it suggested that new oceanic crust was forming at the ridges and pushing the existing crust apart. It also explained the symmetric pattern of magnetic striping found on either side of the ridges.
Further evidence, such as the mapping of earthquake and volcano distribution and the study of deep-sea trenches, confirmed the idea of plate tectonics. The theory was then successfully able to explain a wide range of geologic phenomena, including the formation of mountains, volcanoes, and earthquakes, as well as the distribution of continents and ocean basins.