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1. Read the following paragraph and comment on sea floor spreading.
Geologists studying the crust under the sea have discovered that under some oceans like the
Pacific Ocean, there are mid ocean ridges or ranges. They are formed by the lava rising up from
the mantle. The eruptions on the ridge create a new ocean floor made of basalt rocks, which then
spreads laterally from the ridge. Thus, the mid-ocean ridges contain the newest crust formed on
the planet. This fresh crust is being slowly pulled away from the ridge widening the ocean basin.
This leads to what'is called 'sea floor spreading'
Answers
Answer:
seafloor spreading, theory that oceanic crust forms along submarine mountain zones, known collectively as the mid-ocean ridge system, and spreads out laterally away from them. This idea played a pivotal role in the development of the theory of plate tectonics, which revolutionized geologic thought during the last quarter of the 20th century.
Shortly after the conclusion of World War II, sonar-equipped vessels crisscrossed the oceans collecting ocean-depth profiles of the seafloor beneath them. The survey data was used to create three-dimensional relief maps of the ocean floor, and, by 1953, American oceanic cartographer Marie Tharp had created the first of several maps that revealed the presence of an underwater mountain range more than 16,000 km (10,000 miles) long in the Atlantic—the Mid-Atlantic Ridge.
Explanation:
