Hello again Christian.
By a fortunate coincidence, we were just chatting to a YEC about this. After nine pages, here's my list of some of the questions he hadn't answered. I've edited them, as some were specific to particular mechanisms he put forward for the Flood.
The original thread is
here --- if Nick returns, you may care to sit in on the argument.
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D : LIFE ON THE ARK
(1) Many fish species are quite delicate when it comes to water Ph, salinity, temperature and oxygen levels. How they survived the deluge? Did Noah have tanks in the Ark? (He would need tanks for fresh water and saltwater fish, since the deluge waters must have completely messed up the subaquatic environment.)
(2) How did Noah manage to maintain the environment on the arc for those creatures that live in low-pressure sub-zero environments and those that live in high-pressure high-temperature environments?
(3) Every modern disease of animals must have come on the Ark, including of course diseases that affect humans. The Ark must therefore have been loaded with bubonic plague, cholera, polio, typhus, typhoid, sleeping sickness, leprosy, syphillis, smallpox, measles, malaria... How did Noah and his family survive?
(4) How many different species did Noah take onto the Ark?
E : GEOLOGY AND THE FLOOD
(1) We have not recognized a worldwide flood deposit (in contrast to the recognized Cretaceous-Tertiary boundary). Where in the geologic column should we expect to find it (i.e., how old would it be)? If it would be 6,000 to 10,000 years old, there certainly should be evidence; heck, we have evidence of all sorts of regional depositional events that occurred during this time frame.
(2) How do YECs explain that layers supposedly deposited during the deluge can be tilted, faulted, folded, buried underneath kilometres of rock (including massive volcanics) or uplifited miles high?
(3) Since YECs claim that sedimentary rocks were formed by sediments deposited during the deluge, diagenesis and lithification must be quite fast, after a couple of thousand tears. Why don´t we see sediments say, deposited by the time of the pharaos, that became rock? Why does loose mud deposited at the bottom of a water body not become rock almost instantly?
(4) Are we to believe that there were igneous intrusions during the Deluge, forming nice tablular dikes in the sediment that was being swirled around, or that stratal deformations characteristic of consolidated rocks formed while the sediments were still being deposited?
(5) How do YECs explain metasedimentary rocks?
(6) Where are the all the tuff, ignimbrite, lava and lahar layers associated with the eruptions that caused or helped to cause the deluge [according to the hypothetical "steam from eruptions" mechanism for the Flood]? (Note that all of them must have the same age!)
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(9) If fossilised creatures were all killed in a global flood, why are 90% of all fossils marine life? Wouldn't land animals be worse affected?
(10) Why are human remains never found in the same strata as dinosaur fossils?
(11) Can you explain the unique fossils of Antarctica in terms of YEC geology?
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F : AFTER THE FLOOD --- DISPERSION AND BIOGEOGRAPHY
(1) How did the plants survive the Flood / their seeds survive to germinate?
(2) After disembarking from the Ark how did the plant-eaters survive until the plants had grown out again, and how did the predators survive until the prey had multiplied?
(3) "Conservation biologists now calculate as a rough rule of thumb that unless a wild population contains around five hundred individuals, it is liable to go extinct, sooner or later. Yet even five hundred is only enough to allow the population to tick over... five hundred, then, is a very conservative figure." How does this square with the story of the Ark?
(4) If only two of each unclean land mammal was taken into the Ark, but there were eight humans, of which at least six formed breeding pairs, then we ought to find higher genetic diversity in humans than in unclean beasts, and we should also expect the most genetically diverse mammals to be whales, which would not have undergone the same (impossible) population bottleneck. But this is not what we find when we study genetics. Why do you think this is?
(5) The Great Pyramid shows no evidence at all of ever having been submerged. Therefore, it must be of post-Flood construction. But it is so old that it must have been constructed within a few hundred years, at most, of the Flood. How was that pyramid built by so few people?
(6) [AiG] explain the distribution of the world's fauna, and that of Australia in particular, by ascribing them to human pastoralists. Australia is home to dozens of unique species of venomous snake. Can you explain how and why anyone would herd these creatures to Australia from Turkey (without, you notice, losing any on the way --- Australian snakes are unique to Australia) and why they didn't, instead, take any domesticated meat animals such as sheep, goats, or cattle? Which humans would be dumb enough to carry polar bears to the Arctic? Tigers to Sumatra? Komodo dragons to Komodo? Crocodiles to Florida? Army ants to Brazil?
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I hope this helps. I haven't bothered to sort this list into a "top ten", because there may well be other objections I don't know about. And it omits, of course, the number 1 argument ---
we know what actually happened. We know the real history of life on Earth, and it isn't what you find in Genesis. In the same way, if someone claims that during the seventeenth century Europe was ruled by giant purple lizards, we can disprove this without finding any faults or fallacies in that proposition itself --- it is sufficient to look at the real history of seventeenth century Europe and its dynasties.