Structure and Biome Ruins.

All structures have a chance of being buried in the ground above zero. and Sometimes Little peices or fragments of broken biome pieces or structures underground in random biomes. so maybe this desert use to be a jungle with a jungle temple. this could also connect with Archaeology when it releases. These small details can add history to biomes and be near archaeology dig areas. This could be a great detail like fallen trees on bedrock and more.