It’s important to note the cohesiveness of the Genesis account. Prior to the flood, we have extremely long lifespans of up to almost 1000 years. We have a description of water coming up out of the ground to water the soil. And then the flood. A cataclysm. And everything changes, including lifespans gradually decreasing afterwards (Genesis 11). Could this all have actually happened?
My suggestion is to check out answersingenesis.org. You may be surprised to find that there is an alternative scientific theory to Darwinism, as well as significant scientific advances (particularly in the field of genetics) that support the Genesis account. If you need a push to get you started, take a look at what has happened to the area around Mt. Saint Helens since the volcanic eruption. When there is catastrophic change involved, landscapes can be changed in a very short period of time instead of taking thousands of years!