When strong winds pick up and carry large amounts of sand and dust, it can create a sandstorm. These storms can be intense and dangerous, with visibility reduced to almost zero.
Sand dunes can be unstable, and when they collapse, it can create a sand avalanche. These avalanches can be powerful and destructive, and can bury and suffocate anyone caught in them.
Some people may find the idea of creatures living in sand to be frightening. For example, there are species of worms and other invertebrates that burrow through sand, as well as sand sharks and stingrays that can be found in sandy areas of the ocean.
In some stories and movies, sand is used as a trap to bury or entrap people or animals. This can be a scary or suspenseful concept.
Sand can also be used as a metaphor for something that is constantly shifting or elusive, which could be seen as unsettling or unsettling.