Are Pompeii and Herculaneum unique? Has anyone ever found or gone looking for similar locations, i.e. volcanic eruption sites in which unfortunate victims – human and non-human –  have been entombed in the volcanic ash, with the possibility of revealing their forms by producing casts from the voids? Such sites, if they exist, could reveal exciting new knowledge about ancient peoples and animals.
Probably the best known is more recent, the 1902 eruption of Mt. Pelée on Martinique, where 30,000 people were killed by pyroclastic flows. I don't know the extent of burial - it appears that the city may have been destroyed more by the ash cloud than the dense part of the flow.