Definition of radiometric dating

Yet lava flows that have occurred in the present have been tested soon after they erupted, and they invariably contained much more argon-40 than expected.1 For example, when a sample of the lava in the Mt. Helens crater (that had been observed to form and cool in 1986) ( age yield incorrect old potassium-argon ages due to the extra argon-40 that they inherited from the erupting volcanoes, then ancient lava flows of unknown ages could likewise have inherited extra argon-40 and yield excessively old ages.There are similar problems with the other radioactive “clocks.” For example, consider the dating of Grand Canyon’s basalts (rocks formed by lava cooling at the earth’s surface).8 Physicists have carefully measured the radioactive decay rates of parent radioisotopes in laboratories over the last 100 or so years and have found them to be essentially constant (within the measurement error margins).

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This is the same age that we get for the basalt layers deep below the walls of the eastern Grand Canyon.4 How could both lavas—one at the top and one at the bottom of the Canyon—be the same age based on these parent and daughter isotopes?

One solution is that both the recent and early lava flows inherited the same rubidium-strontium chemistry—not age—from the same source, deep in the earth’s upper mantle.

Yet the same uranium decay also produced abundant helium, but only 6,000 years worth of that helium was found to have leaked out of the tiny crystals. Not Billions (Master Books, Green Forest, Arkansas, 2005), pages 65–78.

This means that the uranium must have decayed very rapidly over the same 6,000 years that the helium was leaking. The assumptions on which the radioactive dating is based are not only unprovable but plagued with problems.

Part 2 explains how scientists run into problems when they make assumptions about what happened .

An hourglass is a helpful analogy to explain how geologists calculate the ages of rocks.

6 The problems with contamination, as with inheritance, are already well-documented in the textbooks on radioactive dating of rocks.7 Unlike the hourglass, where its two bowls are sealed, the radioactive “clock” in rocks is open to contamination by gain or loss of parent or daughter isotopes because of waters flowing in the ground from rainfall and from the molten rocks beneath volcanoes.

Similarly, as molten lava rises through a conduit from deep inside the earth to be erupted through a volcano, pieces of the conduit wallrocks and their isotopes can mix into the lava and contaminate it.

We find places on the North Rim where volcanoes erupted after the Canyon was formed, sending lavas cascading over the walls and down into the Canyon.

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