There are actually a lot of oft-used tropes here, but the stories it most reminds me of are:
- Murray Leinster's "Sidewise in Time": An event has induced a sort of earthquake that spawns time & distance across universe - so a patch of earth is replaced with another patch that is from somewhere else in space-time.
- Jack Williamson's "The Metal Man" (download text scans): An isolated place on earth that no one visits, or can visit, hides utterly alien life-forms & culture.
Story summary.A recent earthquake near a hill or mountain called Huascan in Peru has created an impenetrable mist over a localized region. Seven young girls walked into it & haven't returned. Locals are terrified.
The narrator, an anthropologist, goes in to investigate, & a major adventure begins...
Fact sheet.First published: Fantastic Universe, May 1954.
Download full text from Project Gutenberg, or Manybooks.
Related: Stories of Henry Kuttner; fiction from 1950s.