What is Continental Drift Theory?
The continental drift theory is the theory that once all the continents were joined in a super-continent, which scientists call Pangaea. Over a vast period of time, the continents drifted apart to their current locations. Alfred Wegener first supported continental drift.
Wegener’s explanation of continental drift in 1912 was that drifting occurred because of the earth’s rotation. This explanation and his theory were not widely accepted. Prior to Wegener, however, many had noted that the shapes of the continents seem to fit together, suggesting some schism in the past.
Before the 1950s, the concept of the continental drift, for the most part, was not even entertained as plausible. In the 1950s and the years that followed, however, geologists began to consider the theory, and in the 1960s, most geologists came to accept that the theory may well be possible. Several factors point to the change in accepting the continental drift theory.
Fossil records from separate continents, particularly on the outskirts of continents show the same species. As well mineral specimens along the supposed break lines of the continents are nearly identical. Some identical species exist on certain continents, like an earthworm common to both Africa and South America suggesting the species could not have spontaneously arisen on both continents without some variations.
Continental drift theory also gained in popularity because of the theory of plate tectonics. Briefly, plate tectonics suggests that the ocean floor began to spread and that the continents existed on “plates” that moved in response to the changing ocean floor. Disruption in the continents, such as earthquakes, were a response to the moving plates. This suggests that certain points of the continents exhibit almost constant, though tiny, movements.
For example, Point Reyes, which is located on the San Andreas Fault line in Northern California, has been measured as slowly moving north at a rate of about half an inch (about 2.5 cm) per year. In fact, some geologists theorize that with continued movement, Point Reyes might eventually become an island.
Not everyone accepts the continental drift theory for many reasons. One reason for the dispute is that the age of the earth is in dispute. Some creationists, for example, believe that the earth is far younger than supposed some geologists believe. Some of these creationists also do not accept carbon dating as a way of determining earth, or fossil records being as old as some scientists claim.
Most scientists, and those not believing in creationism, accept the continental drift theory, along with the theory of plate tectonics. Those endorsing the theory of intelligent design usually accept continental drift as well, but assert that a spiritual presence designed and created the earth. Continental drift theory is now taught as accepted theory in public schools throughout the US.
1 inch is 2.5 cm
@anon236770: You don't think that the tides did this, do you? I mean, it was the plates moving that caused the continents to shift.
Very interesting to think we all used to be one continent.
It has helped me so much. My lecture had instructed me to read on this theory and I failed to get it in the library. I wish you could include the finer details.
I believe a little in the continental drift theory, because for me, the theory works with miracles.
Pangaea did not divide easily. It took time but not perfectly as our continents look right now.
what did Pangaea look like?
will this continental drift theory happen again?
what is the meaning of drift?
what is continental shift?
yes this is very cool but what about stationary continents and that theory and evidence for and against it? --a school student
I am learning about this in science and this is very helpful. I have to write a paragraph about it and so far it is going great! Thanks to this website!
I love this site! I use it all of the time and it has answered all my questions, which is great because I am taking geography GCSE and need to know my stuff!
I'm learning about this in science at the moment! It's great to find out about how our world is today.
that theory is true, but it takes time!
are you sure the earth's not just expanding and creating more surface?
what do we exactly mean by tectonic plates?
The theory of continental drift and plate tectonics are amazing. I have been teaching it here in Kenya for six years and the students have appreciated the contributions made by Wegener, Plato and Socrates, among others, in trying to understand the movements of the Earth. However, the concept of sea floor spreading has not been very clear. Thank you. Mr. Okumu
There are very cool continental drift animations that you can find online for free that show what some believe the process of continental drift to have looked like as the continents moved during the precambrian, paleozoic, mesosoic, and cenozoic periods.
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