Table of Contents
- 1 How do mid-ocean ridges support the theory of plate tectonics?
- 2 How the new evidence of mid-ocean ridges added support to Wegener’s theory of continental drift?
- 3 How did continental grooves support the theory of continental drift?
- 4 Why are mid-ocean ridges elevated?
- 5 How do ocean ridges and deep sea trenches support the theory?
- 6 What evidence helped give strong support for the hypothesis of seafloor spreading at mid-ocean ridges?
- 7 How do distinctive rock strata support the theory of continental drift?
How do mid-ocean ridges support the theory of plate tectonics?
Mantle convection drives plate tectonics. Hot material rises at mid-ocean ridges and sinks at deep sea trenches, which keeps the plates moving along the Earth’s surface. Hot mantle from the two adjacent cells rises at the ridge axis, creating new ocean crust.
How the new evidence of mid-ocean ridges added support to Wegener’s theory of continental drift?
In 1915, Wegener proposed his continental drift theory. He said that the continents floated atop the mantle-a heavier, denser layer of rocks deep within the earth. This evidence led early marine geologists to deduce that the mid-ocean ridges were formed by seafloor volcanoes.
How did continental grooves support the theory of continental drift?
If the continents are set adjacent to one another at the south pole, these striations line up with each other. This aided Wegener’s theory that the continents were once all joined as a single landmass.
What supports the theory of continental drift?
The evidence for continental drift included the fit of the continents; the distribution of ancient fossils, rocks, and mountain ranges; and the locations of ancient climatic zones.
What is the mid Atlantic ocean ridge Why is it important?
Mid-ocean ridges are geologically important because they occur along the kind of plate boundary where new ocean floor is created as the plates spread apart. Thus the mid-ocean ridge is also known as a “spreading center” or a “divergent plate boundary.” The plates spread apart at rates of 1 cm to 20 cm per year.
Why are mid-ocean ridges elevated?
At the ridge, new crust forms by igneous intrusion and extrusion. Since hot rocks are in a more expanded state and then contract as they cool (as they spread away from the ridge), the midocean ridges stand up high above the surrounding seafloor. The seafloor depth increases with distance away from the midocean ridges.
How do ocean ridges and deep sea trenches support the theory?
New crust can be observed being formed on the sea floor ridges. Matching magnetic lines of reversal along both sides of the ocean ridge also lends support to the theory of sea floor spreading. The subduction zones which form the deep sea trenches also support the theory of sea floor spreading.
What evidence helped give strong support for the hypothesis of seafloor spreading at mid-ocean ridges?
This hypothesis was supported by several lines of evidence: (1) at or near the crest of the ridge, the rocks are very young, and they become progressively older away from the ridge crest; (2) the youngest rocks at the ridge crest always have present-day (normal) polarity; and (3) stripes of rock parallel to the ridge …
How do continents drift?
Today, we know that the continents rest on massive slabs of rock called tectonic plates. The plates are always moving and interacting in a process called plate tectonics. The continents are still moving today. As the seafloor grows wider, the continents on opposite sides of the ridge move away from each other.
How does the shape of the continents support the Theory of plate tectonics?
For billions of years, plate tectonics built and fragmented supercontinents—land masses made of multiple continents merged together. Plate movement slowly breaks apart the supercontinent. This sends pieces across the ocean to collide and form a new supercontinent, which will also eventually fragment.
How do distinctive rock strata support the theory of continental drift?
How do distinctive rock strata support the Theory of Continental Drift? Geologists have discovered distinctive patterns in rocks in continents that are now thousands of miles apart. By having matching patterns it indicates that the two continents and their rocks were at one time one continent.