Continental drift is not a geological "event". The Earth is a dynamic or constantly changing planet. The thin, fragile plates slide very slowly on the mantle's upper layer. German scientist Alfred Wegener formed this idea of Continental Drift. He argued that todays continents once formed a single landmass, which he named Pangaea (Greek for "all land").
The Earth's crust is constantly moving, both vertically and horizontally, at rates of up to several inches a year.
One of the more difficult ideas for people of all ages to comprehend is the immensity of time over which the Earth has formed and evolved. While most people have some sense that Biology has an evolving history, the physical Earth has one, too, and they are inextricably linked together.
The main features of plate tectonics are:
The Earth's surface is made up of a series of large plates (like pieces of a giant jigsaw puzzle).
These plates are in constant motion travelling at a few centimetres per year.
The ocean floors are continually moving, spreading from the centre and sinking at the edges.
Convection currents beneath the plates move the plates in different directions.
The source of heat driving the convection currents is radioactive decay which is happening deep in the Earth.
2007-03-06 03:35:10
·
answer #1
·
answered by Answergirl 5
·
0⤊
0⤋
Continental Drift is not a geological event, it is a discarded theory that was replaced by the Theory of Plate Tectonics and Seafloor Spreading. The idea was that the two coastlines of the Atlantic Ocean could be pieced together. Furthermore, similar rocks were present when this reconstruction was made. A perfectly sound theory, except that it had no mechanism causing the continents to drift. With advances in mapping the ocean floor, along with data showing where the majority of the Earth's seismic activity occurred, it became apparent that new crust was constantly being created at the mid-oceanic ridges, and destroyed at some continental margins and isolated oceanic regions. Geoscientists proposed mantle convection as the reason for crustal movement. That is, in a nutshell, the gist of our present understanding of the Earth.
2007-03-06 04:54:27
·
answer #2
·
answered by Amphibolite 7
·
0⤊
0⤋
Continental drift is a theory proposed by a German geologist and meteorologist Alfred Wegener in 1915. According to this theory, parts of the Earth's crust slowly drift atop a liquid core. The fossil record supports and gives credence to the theories of continental drift and plate tectonics.
Hope this helps!
2007-03-06 03:37:05
·
answer #3
·
answered by A.Samad Shaikh 2
·
0⤊
0⤋
if u r testing me then i cant give u a perfect answer.
anyway, Continental Drift was formulated by Wegner describing how the continents of the earth today were once a supercontinent called Pangaea. However, because Wegner could not explain why the supercontinent broke up, the plate tectonic theory became accepted
2007-03-06 02:20:19
·
answer #4
·
answered by Anonymous
·
0⤊
0⤋
Continental drift in not a specific event buddy!!!!!!!! It is a concept which gives an account to explain that continent where once together and broke down into sevral pieces and slowly began to drift apart and it is theory(not an event) which did not explain properly how or by what mechanism the land mass were made to move or drift apart which was later adequetly substantiated and properly explained by "Platetectonics theory".
2007-03-06 03:34:53
·
answer #5
·
answered by anusen1970 2
·
0⤊
0⤋