Grand Canyon Age Changes Again
Is the Grand Canyon old or young? Both, geologists are now saying. The latest theory, though, is unlikely to end the 140-year debate.
As if on cue, the leading science news outlets simultaneously issued stories about the Grand Canyon’s age. This is because they are all in cahoots with an “embargo” process that doesn’t let the public learn about a paper till all the talking points and artwork are ready. PhysOrg, New Scientist, National Geographic, Live Science, the BBC News, Science Now and Nature News were all ready with the same line, differing only in minor details, headline and wording.
The basic ideas are these: There’s been a 140-year controversy about the age of Grand Canyon. Recent theories have battled between ages of 5 million years up to 70 million years (11/29/12). American geologists publishing a new paper in Nature Geoscience used helium thermochronometry throughout the canyon and got dramatically different results from place to place. They decided that parts of the canyon are young, 5-6 million years old, some are middle-aged, 15-25 million years old, and some are old, 70 million years old. The canyon, they surmise, consists of five “paleocanyons” (draining different ancient rivers) that were joined together 5-6 million years ago by the Colorado River. So that’s the official word—for now. But will it satisfy the warring parties?
Not likely. This combo plate approach pacifies some geologists while aggravating others. It raises new questions, too. Moreover, everyone admits that the dating methods are unreliable; they depend on assumptions, and on how the results are interpreted. Here are indications all is not well:
- “It will take a bit more time to understand fully why their interpretations are so different from ours and why they conclude that the erosion history varied so dramatically within this short reach of the canyon,” [Rebecca] Flowers says. (New Scientist)
- Not everyone is convinced. Brian Wernicke, a geoscientist at the California Institute of Technology in Pasadena, points out that interpreting thermochronology data, especially fission-track data in terrain where erosion carves downward as well as sideways, is notoriously difficult. (National Geographic)
- The new findings, which rely mainly on reinterpretations of other scientists’ work, summarize decades of geologic sleuthing. But the study may do little to resolve the heated debate over the age of the Grand Canyon. (Live Science)
- But the debate over the Grand Canyon’s age has raged for decades, in part because so much of the canyon’s history is missing, carried away by the river. The little that’s left means many things to many people. The argument also hinges on how one defines the Grand Canyon. Is there a Grand Canyon without the Colorado River running through it? (Live Science)
- So another huge puzzle remains: Where did the river flow before the Grand Canyon formed, and why did it finally end up in the Grand Canyon? “To me, the greatest remaining mystery is how this got connected into a canyon,” said Joel Pederson, a geomorphologist at the University of Utah, who was not involved in the study. (Live Science)
- Pederson agrees that Karlstrom’s reanalysis won’t resolve the Grand Canyon age debate, especially because geochemists can continue to debate how the cooling ages are interpreted. “You have two groups of people who can take the same samples from the same results and come to really different conclusions,” Pederson told LiveScience’s OurAmazingPlanet. “That’s the key battle.” (Live Science)
- Whether Karlstrom’s and colleagues’ paper will actually end the debate that has raged for 140 years remains to be seen. What is in little doubt is the great splendour of the canyon. (BBC News)
- The debate over the age of the Grand Canyon has been so drawn out largely because nature leaves so few clues as to the shape of the land tens of millions of years ago. Water must flow downhill to create canyons, but which way was down ages ago? (Science Now)
- “There will be battles yet”…. The paper is getting a warm if not quite as categorical reception …. But battles there will be…. Karlstrom would settle for researchers’ applying all three of the current methods to the same rocks so that interpretations would be more likely to converge. That will likely take more collegiality than seen to date. (Science Now)
- This explanation aims to reconcile a flurry of seemingly contradictory findings that enlivened discussion about when the canyon was carved…. Still, these findings may not be the last word on the matter…. Small changes in assumptions can mean big changes in interpretation…. “They’re not thinking this through.” [Wernicke] …. It remains to be seen where the debate might move next. (Nature News)
These excerpts contradict Live Science‘s claim that “the big picture is getting clearer.” Missing data – assumptions – interpretations – all these have to be factored in by people who were not there and don’t know. Live Science‘s article hinted that some geologists actually consider a dam-breach flood mechanism (championed by creationists) not too implausible:
For now, here’s Karlstrom’s big picture: About 6 million years ago, something prompted the Colorado River to shift gears and head southwest. That event could have been a lake flood, climate change or subtle shift prompted by erosion. Whatever happened, the Colorado River grabbed its chance, cutting through the ancient rocks lining the gorge (up to 1.8 billion years old at the bottom) and bursting through to the Gulf of California.
Perhaps New Scientist put it most succinctly: “It may be famous, but nobody knows how old the Grand Canyon is.”
Speaking of Grand Canyons, another one deeper than Arizona’s has been found under Antarctic ice (see Science Daily, Live Science and National Geographic). This adds to the one under Greenland (8/29/13). Kings Canyon in California and Hells Canyon in Idaho are deeper than the Grand Canyon.
What’s a park ranger to do? The canyon is old: change the interpretive signs. No, it’s young. Change the signs. Whoops, it’s old again. Change the signs back. Well, then again, maybe parts are old and parts are young. Auggh!
Think about this situation for a minute. Geologists have been arguing about the age of Grand Canyon for almost 150 years, and are no closer to an answer. “Combo plate” theories are generally disfavored in science because of Occam’s Razor (which, itself, was not handed down from heaven). The new theory seems more designed to placate warring parties than to solve the problems “OK, Flowers, you can have 70 million years for this section, and you, Pederson, get 5 million for this section. You over there, you get 15-25 million years to play with. Everybody gets to compete, and everybody wins! Aren’t we all happy people!” No, they’re not. The only thing they agree on is the “splendor of the canyon” – that’s why all the articles contain pretty pictures (see Sidestepping in the Baloney Detector).
Another combo-plate evasion is shown in the “whatever happened” line from Live Science: “a lake flood, climate change or subtle shift prompted by erosion. Whatever happened…” Try that kind of answer in school: “Either the dog ate my homework, or it got shredded in the washing machine, or my sister stole it. Whatever happened, I don’t have it. I know! It was climate change!”
Science can tolerate disagreement for a time, as long as there are strong reasons to believe the debating parties are converging on a good answer (strict Kuhnians will doubt even that). For instance, in the 1940s, geneticists were busily debating the physical nature of the gene. Watson and Crick published the DNA structure in 1953, but it wasn’t till about 1970 that everyone was convinced that all organisms use DNA for genetic inheritance. The answer converged due to better techniques that gave better evidence. The situation is very different here. Nobody knows the right assumptions for the dating methods, nobody knows the right interpretation, nobody can see what the landscape looked like before the canyon, and much of the evidence is inaccessible, having been washed away by the river. In the quotes above, some scientists have no confidence they will ever be able to get a solid answer. (That’s good for them – job security.)
When you explore the canyon, there is nothing obvious about different sections that can justify thinking they belonged to different canyons tens of millions of years apart in age. Nobody has ever observed or experienced tens of millions of years, for one thing, and the same layers of rocks appear throughout the canyon and throughout much of the Colorado Plateau. All the layers are recognizable in all five sections. If the dating methods are assumption-based and hard to interpret, what confidence can anyone have in their counter-intuitive results? Who are you going to believe, them or your own eyes? The dates for the same canyon differ by 65 million years! Think of how mind-boggling that much time is. Whole continents could rise or fall in less than that, according to their own beliefs. Reason, now: if you have a dating method, but you don’t know what assumptions to use, and how to interpret the results, what good is it? It can provide whatever answer your worldview needs.
In the Flood model, there’s a plausible account of how the sediments were deposited, as well as how they could have been carved rapidly when still soft. It’s not miraculous. Flood theory uses known physical mechanisms, except on a “grand” scale. We can see analogs in smaller canyons, in the Channeled Scablands of Washington, and in the canyons below Mt. St. Helens. These show that it doesn’t take long to get massive erosion over a wide area. Additionally, creationists can appeal to other observational evidence for rapid canyon formation: the nautiloid beds, the lack of truncated faults, the huge boulders in the Tapeats, exposures of massive soft-sediment deformation across multiple formations (of different “geological ages”), evidence for hypercanes in hummocky cross-stratification, and more. They can show that radiometric dating methods give vastly inconsistent results, sometimes implausible (like “young” volcanoes on the rim dating “older” than volcanic layers at the bottom). What’s more, the Flood model is parsimonious. Creationists don’t need to invent ad-hoc stories to explain away gaps between strata of 6 million years, 10 million years, 100 million years, a billion years – gaps required by evolutionary theory that left no evidence of their existence. It’s time for Biblical creationists to get more gumption for arguing against long ages as ignorant folly by secular ideologues.
The evidence fits the creation model much better. There are debates between creationists about details, to be sure, but nothing on the scale reflected in the quotes above. The secularists have such large problems because they have a prior commitment to an old earth. Given their indoctrination throughout school, we can understand the secularists’ incredulity at Biblical dates of 6,000 to 10,000 years (Bill Nye’s attitude is typical—see Evolution News & Views video clip). OK, then, will they accept 30,000? A hundred thousand? How about a million? Of course not, because the Darwinians would never let them get away with ages that low, because they need the time for Tinker Bell to make birds out of dinosaurs and scientists out of amebas. But the long ages are unobserved and racked with problems! Secular geologists may know how to read helium levels in a rock, but they don’t know, and cannot know, the answer to the question before them. Why should anyone follow the pied pipers who can’t converge on a reasonable answer for 140 years of trying? Time’s up. Think outside the box.