How can we tell that Genesis 1 doesn't offer scientific information?

Someone asked a question along these lines on Facebook recently, asking what one piece of evidence in particular persuades people to adopt the view that they do.

There are multiple things that I find particularly indicative. The reference to a dome in Genesis 1 is itself significant. But the point becomes even clearer if one knows other creation stories from the Ancient Near East.

In the Enuma Elish, the Babylonian creation epic, Marduk slays Tiamat (their version of the more familiar Hydra, a seven-headed dragon representing the sea). He uses half to make the sea and half to make the sky, fixing an arch to hold up the latter. In other words, waters above and below, the former held up by a dome or arch or whatever one wishes to call it. Just like in Genesis.