Dead ‘Ol Pits Society – Grand Canyon of the Colorado

America has a significant contingent of science denialists. This country – which gave the world nuclear energy, nuclear weapons, lasers, da innernet, men on the moon, and the first spacecaft to exit the solar system – is the same country which maintains such profound ignorance as the common belief that Alley Oop‘s companions really were dinosaurs!

Science denialists come in more flavors than Baskin-Robbins ice cream. Some of their differences are extreme, with no possibility of being regarded as differences in emphasis. Nearly all are united in their divine inspiration for deeply-held, irrational, non-objective beliefs which are frequently contradictory. It is a strange facet of religious belief that nearly all adherants to the Immutable and Irrevocable Word of God cannot agree on what it says, and cannot espouse beliefs which do not crumble and mutate when confronted by reality.

My readers remember reality. Most of you are actually on a first-name basis with reality. E v e r y o n e  knows about Galileo (often a bit inaccurately) and his confrontation with Big Religion over geocentrism. The sleight-of-hand that ensued, eventually – with the blatant exemplars of European seafaring globetrotters – is an indisputable disproof of the infallibility of any religion’s Great Earthly Prophet.

Many Americans are simply afflicted with a mild ignorance or confusion, even about things which they studied in school. If you are one such person, I sympathize with you. It can be hard to keep some of this stuff straight in your mind’s bookshelf of stuff. I spend a lot of time doing just that – allow me to be your librarian.

[ View from Grandview Point ]

The Grand Canyon of the Colorado continues to erode and to amaze. It continually offers new discoveries.

It is a typical big ditch, in being formed as the land was lifted, leaving rain to exit the region by ever-deepening channels. We know the age of the Canyon generally, from knowledge of how erosion works. We know the age specifically from excellent technigues such as radioactive-decay dating. It is at least 5-6 million years old.

Some rocks, such as calcite and zircon, can retain uranium [U] in the overall crystal structure. Most importantly, they can’t retain lead [Pb]. Various isotopes (differing weights) of uranium decay radioactively into other elements – eventually into various lead isotopes. Depending upon whether the lead has been lost or not, various measurements of the uranium and lead isotopes reveal the time since the rock was heated above a certain temperature (900C for zircon). The analysis of the measurements uses ratios, not absolute amounts, so the analysis only shows changes due to time.

That explanation may have made your head twizzle and pop. If so, sorry about that! The general knowledge of erosion is (I think) more compelling evidence for you non-science-geeks.

Imagine your kids’ sandbox, with the sand smoothed and almost level – there is a small slope. Now, consider a lawn sprinkler, set to a fine, gentle mist, wetting the sand for a minute every hour or day. You know what would result! You have seen this before – the sand will develop a network of channels, rivulets, and meanders such as seen on many maps.

Next, imagine having the sprinkler set to deliver a continual stream of water onto a small area of the sand. The result will be utterly different than for a mist. There will be straight, deep gouges (gorges?) which will only meander if the sand box is very long.

The mere appearance of the miniature streams and rivers of a sandbox are indicative of the time elapsed during its formation. This time-scale-dependent behavior is fundamental and unavoidable.

Finally, consider the ad hoc explanation for the Grand Canyon offered (insisted upon) by ‘Young Earth Creationists‘. These folks assert, for religious reasons, that the earth is, at most, 10,000 (or maybe 6,000) years old. Their explanation for the Grand Canyon is that it was formed by a cataclysmic flood, produced by the failure of an unknown natural dam. They imagine that the Canyon formed in 1 to 100 years (more than 6,000 years ago).

You know, from observing the real world in a sand box, that a Grand Canyon formed from a cataclysm would be very different from what it actually is. It would be straight, as the flood could not be deflected readily. It would have a large proportion of boulders and large rocks compared to the amount of small rocks and sediment. There would be few branches.

The real Grand Canyon, and the essence of its magnificent beauty, is utterly different from this imaginary alternative. It is branched, meandering, and a prolific producer of sand and silt. Its form exactly matches the erosion processes, slow and certain, which continue to shape it.

Friends, remember that, where an opinion differs from well-developed science by a factor of 1,000 (6 million years versus 6 thousand years), the truth may lie in your own back yard.

Future edition: Dead ‘Ol Pits Society – Barringer Meteor Crater