Plate Tectonics question?? QUICK PTS.?

Question

What are four pieces of evidence that support the theory of plate tectonics? Explain how or why they support the theory. I need the WHOLE answer. Thanks. Quick points.

Answer 1

Okay, lemme take a crack at this one.

The first piece of evidence was Alfred Wegener's notion of "continental drift" (1912). He noticed that Africa and South America, for example, look like they once fit together like pieces of a jigsaw puzzle. He also found rocks, fossils, plants, and mountain ranges on different continents (e.g., Europe and North America) that appeared to have been together at one time.

Now they can measure continental drift with GPS lasers.

The next thing I guess they found was "seafloor spreading", probably in the 1960s. There's a "Mid-Atlantic Ridge" in the ocean; on either side of it, the magnetic orientation of seafloor rocks alternates symmetrically, coinciding with reversals of the earth's polarity over time. This shows that the Atlantic is getting wider.

They found several deep ocean trenches where the seafloor is diving beneath continental crust. These are the deepest places in the ocean, and they include the Marianas Trench, the Andes Trench, the Java Trench, the Japan Trench, the Philippines Trench, and others.

The pattern of volcanos along the Pacific's "Ring of Fire" provide more evidence. These occur when seafloor subducts beneath continental crust, heats up, forms magma pools, and erupts in a volcano. The Cascade mountain chain in the Pacific Northwest is an example.

Continental crust is comprised of very old rock. Some precambrian rock is 4 billion years old. Oceanic basalt is much younger, the oldest being a mere 200,000 years. The oldest seafloor is near the continental shelves, and the youngest is near the mid-ocean ridges where the seafloor is spreading.

They found ocean fossils near the top of Mt. Everest. The Himalayas formed when India slammed into South Asia.

Ummm ... I guess that's enough for you.

Answer 2

1. Continental drift: the idea that continents were once joined together and have split and moved away from each other. (Pangea breaking and becoming the 7 continents that we know now)

2. Seafloor spreading: hypothesis that the sea floor forms at the crest of the mi-oceanic ridge, then moves horizontally away from the ridge crest toward an oceanic trench.

3. Polar wandering: it was found that the poles were in different positions than the present poles.

4. Distribution of plants and animals in different continents: fossils that were found in one continent were found in another continent.

Answer 3

1)Mountains,2) earth quakes,3) tsunamis, 4)volcanoes
1) the mountains are formed by them pushing on each other
2) Quakes are release of tension on the plates from being forced together
3) From underwater movements of the plates
4) from cracks that go to the next layer of earth

Answer 4

Water,Earth,Fire and Air.