Denoting rocks composed of broken pieces of older rocks.
- ‘Mechanical deposition, by water or wind, produces clastic rocks composed of broken fragments, generally of silicate minerals and small pieces of rock: sandstones and conglomerates.’
- ‘The Allouez Conglomerate is composed mainly of red-colored clastic rocks with lesser amounts of sandstone and siltstone.’
- ‘In contrast, the Cambrian clastic rocks are characterized by a paucity of these zircons, suggesting a significant difference between Neoproterozoic and Cambrian drainage systems.’
- ‘The upper unit consists of red continental clastic rocks of presumed Pcrmo-Triassic age, overlain by Triassic carbonate rocks.’
- ‘No volcanic or clastic sedimentary rocks were obtained from Cavalli Seamount.’
Late 19th century: from French clastique, from Greek klastos broken in pieces.