Ar-Pharazon and the separation of Valanor

[Phrim]

For reference, here's the passage being referred to:

And all the fleets of the Númenóreans were drawn down into the abyss, and they were drowned and swallowed up for ever. But Ar-Pharazôn the King and the mortal warriors that had set foot upon the land of Aman were buried under falling hills: there it is said that they lie imprisoned in the Caves of the Forgotten, until the Last Battle and the Day of Doom.

I don't think Ar-Pharazôn and his army were ever separated from Aman, from the text it seems to me that they were buried within Aman. Regardless of where they are, though, there is nothing to point that Ar-Pharazôn's army founded any sort of strange underground society or the such. There needn't be any descendants or whatnot. The way I read it, the army would be in some sort of stasis until the "Day of Doom".