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The Restless Earth

When we disembark from a cruise ship, we often say how good it feels to stand on solid ground. Although we don’t notice it, we are actually still cruising, because the ground under our feet is moving. Whole continents are drifting like giant rafts on a sea of molten magma.

The earth’s surface is broken into big pieces called plates, roughly thirty miles thick. These plates are constantly moving. A force inside the earth, thought to be from the convection in the earth’s mantel, drives the motion of the plates. North America is slowly drifting westward. The Pacific plate is moving northward, scraping along the edge of the North American plate. The result of this tremendous force is the San Andreas Fault, which cuts through the State of California for over one thousand kilometres.

We don’t notice the leisurely movement of the continents, because it’s less than two centimetres a year. But this almost imperceptible movement can now be measured. One method uses satellites and two observatories on different continents. By aiming lasers at the same satellite and measuring the reflected beams, scientists can calculate the distance between the observatories. These techniques are so sensitive they can detect changes of only ten millimetres in the position of a continent.

So next time someone claims the earth moved, don’t doubt them.

http://pubs.usgs.gov/gip/earthq3/move.html
U.S. Geological Survey

It’s amazing to think that things as large as continents are moving. We don’t notice it for several reasons: the movement is slow and the distances small; we’re so close to the movement; it isn’t having any strong impact on our lives day by day.

This makes me think of the way we age. From one second to another, we notice no change in our bodies. Leaving the sudden on-set of disease or trauma aside, our bodies seem remarkably stable. The facial wrinkles, the protruding stomach, the sagging muscles, the greying or falling hair beset us so slowly and the individual changes are so small that we don’t notice them. We’re also so close to this action that we don’t notice it any more than we do continental drift. Others can often see changes in us that we haven’t noticed. Finally, the host of little individual changes, many happening at the cellular level, don’t have much impact on our lives day by day.

Another factor in observing change is the fact that we often are simply not looking for it. We have a certain image of our bodies and when we look in the mirror each day, the little changes fail to register because we already think we know what we look like. We sometimes unconsciously lie to ourselves, thinking that if we can’t see something, it isn’t there.

Most of us have probably heard someone say something like this: “I’ve made up my mind. Don’t confuse me with facts.” Even if we don’t say this, we sometimes live our lives this way.

If you choose to believe that continental drift is not happening because you can’t observe it personally, you’d be wrong, but it wouldn’t make much difference to your life. There are lots of other things that fall into the same category. In fact, science has made a point of demonstrating that a lot of preconceived notions are incorrect.

However, there are some matters which may not have a big effect at any given moment, but being wrong about them could lead to tragedy. Many people choose to believe that God does not exist because they can’t observe Him directly. To bolster this presupposition, they search for naturalistic explanations for the everyday evidence of God in creation. This does not seem to make a big difference in day-to-day life. In fact, it may seem like an advantage, because they live without accountability. But we all are accountable to God, whether or not it seems like it.

David Humphreys and Ron Hughes
© August 2004