On the third day, God speaks and the oceans obey. Targum Pseudo-Jonathan on (Genesis 1:9) specifies what the Torah leaves vague: it is the lower waters — the ones that remain beneath the heavens after the firmament divided them — that must gather into one place. The upper waters stay where they are.
Then the earth is dried. The language matters: the land is not created here, it is revealed. It was always beneath the water. Creation, the Targumist hints, is often less about making something new than about moving something aside so what was hidden can be seen.