What is formed at mid-ocean ridges as magma rises and cools?
New oceanic crust is formed at mid-ocean ridges. It then cools and solidifies in the center of the ridge. The rising magma pushes up between the plates and drives them further apart. As new crust is forming at the spreading center, it pushes the older crust apart.
What evidence supports Hess’s theory of seafloor spreading Check all that apply?
-fossils of the same animals found in different areas – the direction iron in ocean rocks points. -the tilt and rotation of the Earth’s axis. – the age of different rocks on Earth’s surface. – pillow-shaped rocks found in the sea.
What happens at Mid-Ocean Ridge during seafloor spreading?
Sea-floor spreading is what happens at the mid-oceanic ridge where a divergent boundary is causing two plates to move away from one another resulting in spreading of the sea floor. As the plates move apart, new material wells up and cools onto the edge of the plates.
What type of boundary is illustrated in Figure 9 1?
Convergent plate boundary
What feature of Earth is labeled A in Figure 9 1?
Resource summary
| Question | Answer |
|---|---|
| What layer of Earth is labeled C in Figure 9-1? Image: Plate_subduction_diagram (image/png) | oceanic crust |
| What process is illustrated by the area labeled G in Figure 9-1? Image: Plate_subduction_diagram (image/png) | subduction |
Which of the following is a geographic example of a transform boundary?
The most famous example of this is the San Andreas Fault Zone of western North America. The San Andreas connects a divergent boundary in the Gulf of California with the Cascadia subduction zone. Another example of a transform boundary on land is the Alpine Fault of New Zealand.
Which of the following geographic features is an example of a fault boundary?
An example of a fault line is the San Andreas Fault, which connects the East Pacific Rise, to the south, with the South Gorda, Juan de Fuca and Explorer Ridges, to the north.
Where do most volcanoes on Earth occur?
Sixty percent of all active volcanoes occur at the boundaries between tectonic plates. Most volcanoes are found along a belt, called the “Ring of Fire” that encircles the Pacific Ocean. Some volcanoes, like those that form the Hawaiian Islands, occur in the interior of plates at areas called “hot spots.”