seafloor spreading and subduction

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    In the seafloor in the Mid-Atlantic ridge really spreading and if it is, what is happening to the other side of the plate if it isn’t being subducted under the crust?

    Carter Brown

    That is a great question, Wes!

    Yes, the Mid-Atlantic Ridge is moving at a common rate for continental movement. But remember this movement has been measured at about 2 cm per year. There are no long-term measurements that have been made based on crustal movement. So yes, at the moment the ridge is growing. But will it still be growing 10 years from now? No scientist has any data on any long-term movement, subduction, or uplift. It would be unscientific for us to state that there will be long-term movement. Science must be based on observation and experimentation.

    As for your question on what is happening to the other side of the crust. Crustal plates are wet and fairly compressible and have the ability to bend and fit spaces to a certain degree. Remember 2 cm per year is very slow. If this movement continued for even a hundred years that would make for only 6.5 ft of total movement. So really subduction is not necessary for this slow of a movement.

    Based on my experience and research in the UM, I have noticed a pattern that cycles are a principle of nature. So I would personally predict that there may be a time in the near future where the Mid-Atlantic ridge will begin to close back together. Then it will reopen and close and repeat. But of course, that’s just my personal prediction. We will have to wait for more long-term data to know for sure!

    Let me know if that answered your question!
    Thank you


    Very interesting. In fact, This whole Universal Model is very interesting. I have already incorporated some of the information into one of our film segments.

    Brooke Mckay

    Film segments! Sounds exciting! Let us know if we can help out anymore, we are all about spreading the truth around!


    Dear W.O.,

    Unfortunately nobody was around to measure the velocity of tectonic plates 6,000 years ago or 6 million years ago, but we do know that the velocity of plate movement has stayed relatively constant over time. Let me explain one of the ways we know.

    Consider the Hawaiian island chain. The Hawaiian islands were formed by volcanic eruptions. There is a volcanic hotspot that oozes magma onto the Pacific Plate. Relative to the hotspot, the Pacific Plate moves NW at 7 cm per year. If plate motion has stayed relatively constant over the last few million years, we would expect to see a new island directly over the hotspot, and the islands would get older and older the further NW of the hotspot they are. Let’s visualize it in a graph. Let’s create a graph that has the age of the Hawaiian islands on one axis, and distance from the Hawaiian hotspot on the other axis. If the plates have been moving at roughly the same velocity since the hotspot started erupting, we would expect to see a linear relationship on our graph. If the plate velocity is variable (as UM suggests) then the relationship would look very irregular and scattered.

    I am happy to report that there is a wonderful linear relationship between age of the Hawaiian Islands and distance from the hotspot, suggesting that the Pacific Plate has been moving at 7 cm/year for many millions of years. Take a look at this link from the Hawaii Center for Volcanology and see for yourself.

    Frank Johnson

    That, of course, is based on the assumption of a 4.6 billion year old earth, as current rock dating suggests. In Volume 11 of the UM, (Age Model, chapter 10, see Summary) this method of dating rocks will be challenged

    Courtney Snell

    Preston, as a geologist you of course formulate your theory of the building of the Hawaiian islands upon another theory, that of uniformitarianism, which says that all current global mechanisms for change continue at the same rate as when the earth originally formed, which deny’s the observable evidence for catastrophism in the mechanisms of the earth’s development, of which there are hundreds in the Universal Model. Maybe you might want to present observable evidence, not theory, to support geology’s theory of uniformitarianism before you attempt to use that theory to support your theory of the age of the Hawaiian islands. You see, you are falling into modern science’s trap – building theory upon theory upon theory, and then calling the result fact because everyone “agrees” with it now.

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