And the EARTH helped the WOMAN,
The earth originally was created pure and later became cursed because of the sin (Genesis 3:17-19) of the first man, Adam. Besides end time events, this book of Revelation is about the redemption of the earth from its sin curse. So it is entirely appropriate that the earth should help the WOMAN.
It was clear to Moses that the Lord is Master over the earth (Exodus 9:29). David declares in Psalm 24:1-2 that the earth is "established upon the rivers". David has it correct in that the earth is superior to rivers. The devil, true to his subversive ways, is trying to make the river superior to the earth. The devil can't succeed.
and the EARTH opened its mouth and drank up the river which the DRAGON poured out of his mouth.
Physically, the African and Indian tectonic plates meet at the Jordan River, Dead Sea, Gulf of Araba, and Red Sea. With all the natural disasters, earthquakes, and stars falling from heaven to earth, it is easy to imagine that the plates shift and "drink up the water" sending it into the Indian Ocean.
Symbollically, the Lord uses the EARTH to keep the WOMAN high and dry. That is, while the DRAGON (devil) tries to destroy God's Chosen people, Israel, through an onslaught of demons (previous verse), the Lord provides a supernatural detour to Sheol (the place of departed spirits). The family of Korah due to exaltation or pride (Numbers 16:1-7) also took that detour (Numbers 16:25-35) straight to Sheol.
Prophetically, Isaiah talks about the protection of Israel (Isaiah 26:20; Isaiah 42:15; Isaiah 43:2; and Isaiah 50:2) in terms of earth covering or water being diverted or dried up.
After the tribulation, Israel will not need to be protected anymore. But it will be "healed" along with all the other nations on the NEW EARTH by the leaves of the trees along the river of the water of life (Revelation 22:2). This is a GOOD river straight from the throne of God and of the Lamb Revelation 22:1)!