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There are two continents with an ocean between them. Today the continents have very different plants and animals on them. However, a geologist found fossils of the same type of organism on both continents. Millions of years ago when this type of organism was alive, we know it lived in only one place. The geologist is using fossils as evidence to argue that the two contients used to be touching. How could the continents have gotten so far apart, and how long did it take for this to happen?

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Answer:

A. Through geologic forces leading to continental drift.

B. It can take up to millions of years.

Step-by-step explanation:

A. Continents rest on tectonic plates (a large slabs of rock). The plates are usually moving and interacting with one another. Seafloor spreading zones and giant rift valleys are the sites where tectonic activity are done.

However, in the process of seafloor spreading, molten rock emerges from within the Earth and produces an oceanic crust (a new seafloor) to the edges of the old one. Seafloor spreading occurs along giant underwater mountain ranges (also referred to as mid-ocean ridges).

Then, as the seafloor grows wider, the continents on opposite sides of the ridge move away from each other over time to experience a define continental drift.

B. The seafloor spreading rates is as low as 2.5 centimeters per year and take up to millions of years to see a well defined drift.

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