Just to play devil's advocate for a second (I'm aware of the irony in that statement), but why would you have such a hard time believing Noah's flood might be possible?
- We know there is enough water to cover the Earth by over a mile if it was flat.
- We suspect there is another oceans worth of water locked up in Earth's crust in ringwoodite.
- We think the continents formed a super continent in the past and have since changed position drastically.
- We have meteor impact craters like Chicxulub that seem to have altered Earth drastically.
- We know strata layers are almost always layed down by water.
- We know animals have to be buried fast in order to fossilize instead of deteriorate.
- We also know that major canyons can be created rapidly (Mt St. Helens) and have no conclusive evidence of them forming slowly.