Noun
a fine-grained sandstone of consolidated silt
Source: WordNetPhoto Credit: Peter Rejcek Scientist Erik Gulbranson splits open a grey slab of siltstone in a quarry on Allan Hills to reveal amazingly well-preserved Triassic plant fossils. Source: Internet
Sediment cores — composed of things like glacial rocks, sand, volcanic ash, siltstone and mudstone — represent layers of time millions of years in the past. Source: Internet