It may be that he swept back into the past, and fell among the blood-drinking, hairy savages of the Age of Unpolished Stone; into the abysses of the Cretaceous Sea; or among the grotesque saurians, the huge reptilian brutes of the Jurassic times.
There are no more uses of "abyss" in the book.
Show samples from other sources
These were men who had built up wealth and social status over long careers and now found themselves looking into the abyss. [of the 1987 stock market crash]
Alan Greenspan -- The Age of Turbulence
The nerve-grinding squeal of the spike cutting through the ground sent a shiver up Thomas’s spine, though a second later the Griever tumbled into the abyss.