Prothero began his talk with the classic, self-serving line of the secularist, “One of the first things I want to make clear is that I am a scientist.”
In other words, you have to believe me because I am no ordinary mortal. I know.
“We deal only with natural forces and things we can observe and test in nature.”
In other words, not like you creationists who believe in things without evidence.
“You can see the layers of the earth piled up one on top of the other in a place like this … Immense amounts of time are required to deposit that, cement it into hard sandstone and shale, tilt it, erode it. Minimum estimate is hundreds of millions of years.”
In other words, Prothero doesn’t deal only with things he can observe.
If I was there I would have said to Prothero, “Hold on. You say you deal only with what you can observe and test but here you are talking about things that you can’t see. You did not observe the sediments being deposited, cemented, tilted or eroded. Your figure of hundreds of millions of years comes out of your imagination.”
Then we could discuss the sorts of processes that could have carved the canyon, processes that no-one has observed and that everyone has to imagine. The time it took depends on the magnitude of the processes involved. Prothero gets the long ages because he decided long ago to exclude the possibility of Noah’s Flood from his thinking.
Maxwell played a trick on the creationists because he confronted them with experts in the field yet the team was of ordinary folk without the specialist knowledge in the areas he took them to. Maxwell seemed satisfied that that they struggled to give answers on topics outside their expertise and which they had not had the opportunity to research.
It would be interesting to take Maxwell to visit some creationist experts in their fields: geology, genetics, tectonics, astronomy and human evolution. It would be interesting to see how well he fares when confronted with evidence he is not familiar with.
As far as the Canyon is concerned, Maxwell should have included a creationist expert in the conversation, someone like Dr Steve Austin or Dr Andrew Snelling. These are two PhD geologists who have done original research in the Canyon and who conduct geological field trips along the Colorado River. They could have illuminated Prothero of some of the amazing evidence for large-scale watery catastrophe in strata in the Canyon, evidence that points to it being deposited quickly and carved rapidly, as you would expect from Noah’s Flood.
J.S.
Dr. Prothero recently wrote about this experience (http://www.skepticblog.org/2012/11/07/a-surreal-journey/), and hypothesized that incised meanders like the ones the group saw at Horseshoe Bend were formed by sideways-eroding alluvial rivers which began carving downward through hard bedrock in response to regional uplift.
However, geologists such as C.R. Twidale have pointed out the amazing mobility of alluvial rivers, and a recent study in Italy suggested that the Po River has changed its course in response to underground structures that don’t even have significant surface topographic expression (1).
Prothero proposed that rapid regional uplift was the mechanism that caused a volatile, sideways-eroding river in a bed of unconsolidated alluvium to abandon its shifting course and begin carving out a solitary meander through hard bedrock.
Yet he does not speculate on how rapid that uplift would have to be to cause water flowing downhill to bypass the path of least resistance. Perhaps if he thought about the force necessary to accomplish such a task, he might find that his theory is not so far from the creationists as he supposes.
(1) Burrato, P., F. Ciucci, G. Valensise, and others (2003), An inventory of river anomalies in the Po Plain, northern Italy: Evidence for active blind thrust faulting, Annals of Geophysics.