Glacier Evidence Of Continental Drift
The evidence which gave ascent to the theory of continental drift, more than accurately known as plate tectonics includes :
The coasts of the continents surrounding the Atlantic ocean could fit together similar a jigsaw puzzle, equally shown on the right, and appear to take originated from one huge state mass. The well-nigh logical explanation was that the continents themselves were once parts of a much larger "super-continent" which was named Pangaea.
Other bear witness supporting motion of the continents was the glacial till deposits in the southern hemisphere. With the continents in their present positions, top right, the till deposits indicate erratic glacier movement. When the continents are fitted together,however, bottom right, they show a much more streamlined motion of the glacier from south Africa and Sooth Australia outward. For the glaciers to take been nowadays with the continents in their current positions, much of the world should have been under water ice. Simply this wasn't the case.
Living animals in widely separated lands are like. For example Republic of india and Madagascar accept similar mammals, which are quite unlike from those in Africa, even though it is now well-nigh to Republic of madagascar.
Fossil plants in India, Due south Africa, Commonwealth of australia, Antarctica and S America are like to each other. This flora is quite unlike from plants found in other parts of the world at the same time.
The same applies to fossil animals. An example is the discovery of fossils of the aquatic reptile Lystrosaurus, shown on the right, from rocks of the same age from locations in South America, Africa, and Antarctica.
There are numerous geological similarities between South America and Western Africa . For example, mount ranges on both continents friction match up, as shown on the right, as do coal fields in North America and Europe
When liquid magma cools and becomes solid stone, some of the minerals in the rock preserve a record of the direction and strength of the magnetic field at that time. This "recording" is called paleomagnetism. Lava is regularly pouring from the mid-oceanic ridges as the oceanic floor moves away from the ridge similar to a conveyer chugalug system. As the lava cools it acts something like a magnetic recording of magnetic reversals. Since the age of the reversals is known, the speed of plate motility tin exist precisely calculated through time.
If we look at the magnetic backdrop of present day rocks, as shown on the left of the image on the right, we can see that at that place is no correlation to the direction of the pole. However if we change the continents as they were during Pangaea and appointment the rocks we find that they align to a mutual pole.
Paleomagnetism tells us how far from the poles rocks were when they formed, by looking at the angle of their magnetic field. The story told by unlike continents is contradictory, and can only be explained if we assume the continents have moved over time.
1) How did fossils provide evidence for continental migrate?
ii) Explain the term paleomagnetism. How is paleomagnetism used to support the theory of continental drift.?
3) Is any 1 piece of evidence overwhelming support for continental drift?
4) What is the geological evidence for continental drift?
v) What are glacial till deposits? How are they used to back up continental drift?
Glacier Evidence Of Continental Drift,
Source: http://www.dynamicscience.com.au/tester/solutions1/space%20science/evdn.html
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