Scientific speculation is where creationism and science diverge.
Science calls scientific speculation a "hypothesis." It is the basis for more research. Wild speculations are completely acceptable because examining such speculations is what leads to learning.
Creationism has an opposite tack. Scientific speculation is where creationism ends. For example, when Spirit Lake was emptied by the Mt. St. Helens explosion, the water from the lake cut a gorge that I was told is one-fortieth the size of the grand canyon.
That gorge was cut in one day.
Could the Grand Canyon have been similarly cut in one day by the waters of an even larger lake?
Sure it could have, and those who practice "creation science," rather than just science, would like to leave it at that. The Grand Canyon could have been carved in one day, so the earth could be only 6,000 years old.
But the question is not whether the Grand Canyon could have been made in one day. The question is, was it carved in one day?
Science seeks to answer that question in order to find out what's true. Creationism seeks to ignore the question, hoping that what it wants to be true won't be proven false.
Oh, were you wondering whether the Grand Canyon was cut in one day?
Sorry about that. No, it wasn't. Rushing water like the water from Spirit Lake leaves a washboard effect on the surface that it scours. The surface of the Grand Canyon doesn't have that washboard effect. It wasn't cut by the escaping waters of the flood.