For the upper bound: https://en.wikipedia.org/wiki/Clair_Cameron_Patterson#Measur...
Grand Canyon: https://www.talkorigins.org/indexcc/CH/CH581.html https://www.talkorigins.org/faqs/icr-science.html https://www.talkorigins.org/indexcc/CD/CD210.html
Erosion: https://www.talkorigins.org/indexcc/CD/CD610.html https://www.talkorigins.org/indexcc/CD/CD620.html
Furthermore, there is abundant evidence for erosion between many of the layers in the Grand Canyon, and they don't look anything like flood deposits, which are generally chaotic (unsorted, discontinuous bedding, etc) because of the high energy in the environment during deposition. Paraconformities indicate a cessation of deposition, which is often accompanied by erosion. They are 'para' conformities not because of the gap in time between the layers, but because there wasn't major deformation of the Earth's crust during that time (this means substantial tectonic activity), which would cause regional tilting of the lower (older) rocks. Throughout much of the middle of the country, there are young sediments deposited in a paraconformable relationship on top of rocks that are 400 million years old (making up the surficial bedrock of the region), because there hasn't been major tectonic activity in the region since those 400 million year old rocks were deposited (and indeed, for close to a billion years before that in much of the midcontinent).
William Smith deserves so much of our respect. Cf, e.g., https://en.m.wikipedia.org/wiki/The_Map_that_Changed_the_Wor..., which summarizes the most excellent book.
Always called it Cow-per (like the livestock). So it's interesting to know I've been wrong all along!
When he died he had assembled a team of people who worked on it. The site is now suffering from a bit of rot (the videos don't serve anymore) but he has been dead for six years so I suppose that's no surprise. I don't know if his "gang" still maintain it, but someone must be paying for the domain and hosting I suppose.
The time and energy he committed to this are astonishing to me, he was a talented man - he had the option to be a partner at Arthur Anderson (progenitor of Accenture) before becoming a CFO at a series of small banks and building societies. His career was firmly on the up, he worked for one of the precursors of what became RBS in the 1980's. If things had gone differently perhaps he would have muzzled "Fred the Shred" and we'd all be the richer, especially his kids. But, at some point a conviction and faith gripped him and he gave up everything for his bible project. He died penniless.
I wonder, because I don't understand, because I just see numerology and over interpretation, does it mean he was wrong? I think so, but perhaps that's just my faith talking.
If you believe your religion's scriptures are an infallible set of truths handed down from above, then you've got the secrets of the universe in your hand and all you have to do to expand your knowledge is deduce correctly from that. It's an addictive hobby, and much easier and less messy than real science, where there's no final authority and you have to work for years to make a small discovery in one area and even then you might fail. Isaac Newton himself got caught up in that sort of thing.
Theology is a huge nerd snipe. Isaac Newton is my go to example for how it's a fixation with a extremely vicious cycle. There are whole manifestations of OCD that are just focused on religion as the core OCD fixation.
If forced to choose between owning a dishwasher, washer, dryer, AC, etc.... I would give up every moment of theology training, argument, etc. and keep the tech.
A big part of the difficulty with theological training is most people are graduating from schools that push hermeneutics that encourage tortured logic of the text. Ultimately training people primarily not to identify truth claims or evaluate propositions but to tie intellectual knots and take primrose paths that fall apart with any holistic scrutiny. Just read the papers coming out and you can easily see that people are graduating with PHD's in mental gymnastics.
All the good I've brought into the world, all the lasting things I've done and they have not had anything to do with theology.
My parents were academics who got nerd sniped by theology as well, the few times they stepped outside of theology they did so much good but all that time spent in theology just left them penniless and, ultimately, dying terribly early.