Could Mesosaurus Swim Across an Ocean? Quick Check
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Question
What did scientists observe in the ocean floor which indicates that the Pacific Ocean is becoming smaller?(1 point)
Responses
subduction
subduction
spreading
spreading
plates floating on the mantle
plates floating on the mantle
continental drift
continental drift
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continental drift
The correct answer is "subduction."
To determine the answer to this question, we need to understand the different processes that occur on the ocean floor. One way scientists can observe changes in the size of an ocean is by studying plate tectonics.
Plate tectonics is the theory that the Earth's lithosphere (the solid outer shell) is divided into several large and small plates that move around on the semi-fluid asthenosphere (the layer below the lithosphere). These movements can result in various geologic phenomena, including the formation of mountains, earthquakes, and the creation and destruction of oceanic crust.
Among the processes associated with plate tectonics, three options are mentioned: subduction, spreading, and continental drift.
1. Subduction: This refers to the process where one tectonic plate is forced beneath another, sinking into the mantle. Subduction zones are typically associated with deep trenches and volcanic activity. This process does not necessarily indicate the shrinking of an ocean, as it can occur at the boundary between two plates.
2. Spreading: This process occurs at mid-ocean ridges, where two tectonic plates are moving away from each other. As they separate, magma rises from below, creating new crust and pushing the existing crust apart. Spreading can contribute to the growth of an ocean, rather than its shrinkage.
3. Continental drift: This refers to the movement of entire continents across the Earth's surface over geologic time. While it can cause changes in the size and shape of ocean basins, continental drift alone doesn't indicate that an ocean is becoming smaller.
Considering the given options, none of them directly suggest that the Pacific Ocean is becoming smaller. However, the closest option is "spreading" because spreading at mid-ocean ridges can lead to the creation of new oceanic crust, potentially increasing the size of an ocean.
To obtain a certain answer to this question, you may need to consult additional scientific research or studies focused explicitly on the change in size of the Pacific Ocean.