Tuff

For other uses, see Tuff (disambiguation).
Not to be confused with Tufa.
Cliff face of welded tuff pockmarked with holes — some natural, some man-made from Bandelier National Monument, New Mexico
Etruscan tuff blocks from a tomb at Banditaccia, Lazio, Italy
A house constructed of tuff blocks in Rieden, Rhineland-Palatinate, in the Volcanic Eifel region, Germany

Tuff is a type of rock made of volcanic ash ejected from a vent during a volcanic eruption. Following ejection and deposition, the ash is lithified into a solid rock.[1][2] Rock that contains greater than 75% ash is considered tuff, while rock containing 25% to 75% ash is described as tuffaceous (for example, tuffaceous sandstone).[3] Tuff composed of sandy volcanic material can be referred to as volcanic sandstone.[4]

Tuff is a relatively soft rock, so it has been used for construction since ancient times.[5] Because it is common in Italy, the Romans used it often for construction.[6] The Rapa Nui people used it to make most of the moai statues on Easter Island.[7]

Tuff can be classified as either igneous or sedimentary rock. It is usually studied in the context of igneous petrology, although it is sometimes described using sedimentological terms.

Tuff is often erroneously called tufa in guidebooks and in television programs but tufa is a form of travertine.

  1. ^ Fisher, Richard V.; Schmincke, H.-U. (1984). Pyroclastic rocks. Berlin: Springer-Verlag. pp. 89–90. ISBN 3-540-12756-9.
  2. ^ Schmincke, Hans-Ulrich (2003). Volcanism. Berlin: Springer. p. 138. ISBN 978-3-540-43650-8.
  3. ^ Schmidt, R. (1981). "Descriptive nomenclature and classification of pyroclastic deposits and fragments: recommendations of the IUGS Subcommission on the Systematics of Igneous Rocks". Geology. 9: 41–43. doi:10.1007/BF01822152. S2CID 128375559. Retrieved 27 September 2020.
  4. ^ Poole, W. H.; Neuman, Robert B. (2003). "Arenig volcanic and sedimentary strata, central New Brunswick and eastern Maine". Atlantic Geology. 38 (2/3). doi:10.4138/1257. Retrieved 2022-09-24.
  5. ^ Dolan, S.G.; Cates, K.M.; Conrad, C.N.; Copeland, S.R. (14 March 2019). "Home Away from Home: Ancestral Pueblo Fieldhouses in the Northern Rio Grande". Lanl-Ur. 19–21132: 96. Retrieved 29 September 2020.
  6. ^ Jackson, M. D.; Marra, F.; Hay, R. L.; et al. (2005). "The Judicious Selection and Preservation of Tuff and Travertine Building Stone in Ancient Rome*". Archaeometry. 47 (3): 485–510. doi:10.1111/j.1475-4754.2005.00215.x.
  7. ^ Richards, Colin (2016). "Making Moai: Reconsidering concepts of riskin the construction of megalithic architecture in Rapa Nui (Easter Island)". Rapa Nui: Easter Island Cultural and Historical Perspectives. Berlin [Germany]. pp. 160–161. ISBN 978-3-7329-0265-1. Retrieved 29 July 2021.{{cite book}}: CS1 maint: location missing publisher (link)