how the Theory of Plate Tectonics has helped us understand the age of the Earth?

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  • 1 decade ago
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    Plate tectonics probably has not directly contributed to "dating" of the earth, but it has contributed significantly in an indirect manner. The magnetic striping of the ocean floor was the smoking gun that led to the theory of plate tectonics, not the other way around. Paleomagnetic dating techniques have been developed separately from plate tectonics, but are very often a key technique used for understanding past plate positions and motion. Understanding plate tectonics also allows a degree of verification of results of paleomagnetic dating, which involves measurements of past earth magnetic polarity. If a new data point disagrees with all the surrounding data points, it either requires a new interpretation of tectonic movement, or is questioned as invalid. While paleomagnetic dating may have led to the theory of plate tectonics, the plate tectonic theory allows the framework for interpretation of paleomagnetic, sedimenatary, paleontologic, and other lines of evidence that go into mapping tectonic movement. One thing you should understand about geoscience is that the field most often applies parallel lines of evidence to reach firm conclusions, and at times that evidence can work in both directions.

    Yet, plate tectonics has contributed significantly to understanding the evolution and motion of the plates over time, which in turn has helped researchers develop other lines of evidence to understand the age of various parts of the earth. To see some examples of how plate tectonics can help with this go to this website:

    http://www.scotese.com/

    In particular check out the 3D animations of plate tectonic movement, and consider how being able to visualize this would help anyone, and especially a scientist who is investigating the age of some particular part of the earth, to understand the past geologic systems. Plate tectonics isn't an essential part of understanding the age of the Earth, but it is an important concept that allows interpretation of widely varying points of data into a comprehensive story. Without the theory of plate tectonics, we would probably still be arguing about the movement of the magnetic poles, and trying to explain global sea level changes over geologic history.

    Source(s): Geologist
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  • 1 decade ago

    The seafloor spreading answer already provided below/above is important, however ...

    The critical thing is that plate tectonics requires motion of plates - the mechanism of this movement is mantle convection. So the question is what is the heat source driving convection? The answer is radioactive isotope decay.

    The discovery of radiation and radioactive decay at the end of the 19th century is very interesting from a history of science perspective,

    Prior to this Lord Kelvin was hypothesising Earth age based on the cooling of a solid body of metal. This gave him an answer that the earth was very young. At the same time Darwin had proposed his theory of evolution which required much longer time periods.

    Rutherford discovered the concept of radioactive decay and half life - this allowed much more accurate dates to be found for rocks on Earth using Uranium isotopes (among others).

    So plate tectonics allows us to place the age of the Earth in context.

    Source(s): I'm a geologist
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  • 1 decade ago

    The above are all very valid answers, and the magnetic stripes inthe sea floor would have been my first answer too.

    I can give a little bit more though - plate tectonics also cause uplifting of certain areas of rock - allowing sedimentary strata to become exposed... by looking at fossils embedded in the strata, we can discover a *relative* age for the earth.

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  • 1 decade ago

    The simple answer is that plate tectonics really has nothing to do with calculating the age of the Earth.

    A more complex answer is that every rock on earth has to be younger than the Earth, as rocks are continuously consumed and re-created as part of the plate tectonic cycle.

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  • Anonymous
    4 years ago

    The problem here is that the Sun is getting about 10% hotter every billion years. So, long before the Sun swells into a red giant, then collapses into a white dwarf, the Earth will have lost all capability to support life. So either either we fight the budget cuts to NASA and get out of Dodge, or we accept that we will be wiped out, along with the rest of life on Earth.

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  • 1 decade ago

    There are symmetrical stripes of differently-aligned magnetic rocks in some ocean beds either side of the mid-oceanic ridge which act as a sort of record of the movement of the continental plates. The continents also fit together, suggesting they used to be in one piece about 200 million years ago. The speed at which the ocean beds spread enables scientists to date various geological events. Mountain building is also explained by it.

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  • 1 decade ago

    It hasn't.

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