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A clastic dike is a seam of sedimentary material that fills an open fracture in and cuts across sedimentary rock strata or layering in other rock types. Clastic dikes form rapidly by fluidized injection (mobilization of pressurized pore fluids) or passively by water, wind, and gravity (sediment swept into open cracks). Diagenesis may play a role in the formation of some dikes.〔Richard J. Davies, R.J.; Huuse, M.; Hirst, P.; Cartwright, J.; Yang, Y., 2006, Giant clastic intrusions primed by silica diagenesis, Geology, 34, p. 917-920〕 Clastic dikes are commonly vertical or near-vertical. Centimeter-scale widths are common, but thicknesses range from millimetres to metres. Length is usually many times width. Clastic dikes are found in sedimentary basin deposits worldwide. Formal geologic reports of clastic dikes began to emerge in the early 19th century.〔Darwin, C., 1833-1834, Geological observations on the volcanic islands and parts of South America visited during the voyage of the H.M.S. “Beagle” (2nd Edition), p. 438〕〔Hay, R., 1892, Sandstone dikes in northwestern Nebraska, GSA Bulletin, 3, p. 50-55〕〔Case, E.C.; 1895, On the mud and sand dikes of the White River Miocene, Ithaca, N.Y., American Geologist, 24, p. 248-254〕〔Cross, W., 1894, Intrusive sandstone dikes in granite, GSA Bulletin, 5, p. 225-230〕〔Crosby, W.O., 1897, Sandstone dikes accompanying the great fault of Ute Pass, Colorado, Essex Institute Bulletin, 27, p. 113-147〕〔Diller, J.S., 1890, Sandstone dikes, GSA Bulletin, 1, p. 411-442〕〔Newsom, J.F., 1903, Clastic dikes, Bulletin of the Geological Society of America, 14, p. 227-268〕〔Ransome, F.L., 1900, A peculiar clastic dike near Ouray, Colorado, and its associated deposit of silver ore, Transactions of the American Institute of Mineralogical Engineers, 30, p. 227-236〕〔Pavlow, A.P., 1896, On dikes of Oligocene sandstone in the Neocomian clasys of the District of Altyr, in Russia, The Geological Magazine, New series, v. iii, p. 49-53〕〔Kirkby, J.W., 1860, On the occurrences of "sand pipes" in the magnesian limestones of Durham, The Geologist (London), p. 293-298, 329-336〕〔Prestwich, J., 1855, On the origin of the sand and gravel pipes in the chalk of the London Tertiary district, Quarterly(?) Journal of the Geological Society of London, v. ii, p. 64-84〕〔Strangeways, W.T.H.F., 1821, Dikes near Great Pulcovca near Saint Petersburg, Russia, Transaction of the Geological Society of London, v. V, p. 386, 407, 408 and Plates 25-28〕〔Cuvier & Brongniart, 1822, Sandstone pipes near Paris, France (''Description geognostiques des Environs de Paris''), p. 76, 134, 141〕〔Murchison, R.I., 1827, Quartz sandstone veins in grit near Kintradwell in Somersetshire, Transactions of the Geological Society of London, 2nd series, v. ii, p. 304〕〔Murchison, R.I., 1829, On the coal-field of Brora in Sutherlandshire, and some other stratified deposits in the north of Scotland, Transactions of the Geological Society, Second Series, 2, p. 293-326〕〔Strickland, H.E., 1838, Calcareous sandstone dikes in Triassic shale at Ethie in Rossshire, Transactions of the Geological Society of London, v. V, 2nd series, p. 599-600〕〔Strickland, H.E., 1840, On some remarkable dikes of Calcareous Grit, at Ethie in Ross-shire, Transactions of the Geological Society, Second Series, 5, p. 599-600〕〔Buckland, 1839, Transactions of the British Association for 1839, p. 76〕〔Lyell, C., 1839, Sand pipes near Norwich, England, London and Edinburgh Philosophical Magazine, 3rd series, v. XV, p. 257〕〔Several more c. 1850 references to dikes in Newsom (1903)〕〔White, E.E., 1916, Analysis of slate and dike, Engineering & Mining Journal, v. 101, p. 433-434〕〔Dana, J.D., 1849, Wide sandstone dikes in bluffs near Astoria, OR, p. 654-656 in Geology, Volume 10 of the U.S. Navy Exploring Expedition 1838-1842, under the command of Charles Wilkes, C. Sherman publisher, Philadelphia, 18 volume set〕 Terms synonymous with clastic dike include: ''clastic intrusion, sandstone dike, fissure fill, soft-sediment deformation, fluid escape structure, seismite, injectite, liquefaction feature, neptunian dike (passive fissure fills), paleoseismic indicator, pseudo ice wedge cast, sedimentary insertion, sheeted clastic dike, synsedimentary filling, tension fracture, hydraulic injection dike'', and ''tempestite''. ==Environments of formation== Clastic dike environments include: *Clastic dikes associated with earthquakes - :An incredible variety of dikes is found in the geologic record. However, clastic dikes are typically produced by seismic disturbance and liquefaction of high water content sediments. Examples of this type are many.〔G. Neef, A clastic dike-sill assemblage in late Miocene (c. 6 Ma) strata, Annedale, Northern Wairarapa, New Zealand, 1991, New Zealand Journal of Geology & Geophysics, Vol. 34: 87—91 http://www.rsnz.org/publish/nzjgg/1991/11.php〕〔Peterson, C.D., 1997, Coseismic paleoliquefaction evidence in the central Cascadia margin, USA, Oregon Geology, 59, p. 51-74〕〔Audemard, F.A.; de Santis, F., 1991, Survey of liquefaction structures induced by recent moderate earthquakes, Bulletin of the International Association of Engineering Geology, 44, p. 5-16〕 Clastic dikes are paleoseismic indicators in certain geologic settings.〔Ettensohn, F.R.; Rast, N.; Brett, C.E. (editors), Ancient Seismites, GSA Special Paper, 359〕〔Kevin G. Stewart, 2003, ''Paleoseismology'' http://www.unc.edu/~kgstewar/web_pages/paleoseismology.html〕 Several qualitative, field-based systems have been developed to help distinguish seismites〔Seilacher, A., 1969, Fault-graded beds interpreted as seismites, Sedimentology, 13, p. 15-159〕 from soft sediment deformation features 〔Mills, P.C., 1983, Genesis and diagnostic value of soft-sediment deformation structures – a review, ''Sedimentary Geology'', 35, p. 83-104〕〔Groshong, R.H., 1988, Low-temperature deformation mechanism and their interpretation, GSA Bulletin, 100, p. 1329-1360〕 formed by non-seismic processes.〔Allen, C.R., 1975, Geological criteria for evaluating seismicity, GSA Bulletin, 86, p. 1041-1057〕〔Guiraud and Plaziet, 1993〕〔Obermeier, S.F., 1996b, Use of liquefaction-induced features for paleoseismic analysis - an overview of how seismic liquefaction features can be distinguished from other features and how their regional distribution and properties of source sediment can be used to infer the location and strength of Holocene paleo-earthquakes, Engineering Geology, 44, p. 1-46〕〔Greb, S.F.; Ettensohn, F.R.; Obermeier, S.F., 2002, Developing a classification scheme for seismites, GSA North-central & Southeastern Section Annual Meeting Abstracts with Programs〕〔Wheeler, R.L., 2002, Distinguishing seismic from nonseismic soft-sediment structures: Criteria from seismic-hazard analysis, in Ettensohn, F.R.; Rast, N.; Brett, C.E. (editors), Ancient Seismites, GSA Special Paper, 359, p. 1-11〕〔Obermeier, S.F.; Olson, S.M.; Green, R.A., 2005, Field occurrences of liquefaction-induced features: a primer for engineering geologic analysis of paleoseismic shaking, Engineering Geology, 76, p. 209-234〕〔Montenat, C.; Barrier, P.; d'Estevou, P.O.; Hibsch, C., 2007, Seismites: An attempt at critical analysis and classification, Sedimentary Geology, 196, p. 5-30〕 :Results from analytical modeling of clastic dike injection in soft rocks〔Levi, T.; Weinberger, R.; Eyal, Y., in press 2010, A coupled fluid-fracture approach to propagation of clastic dikes during earthquakes, Tectonophysics〕 indicate propagation occurred at a rate of approximately 4 to 65 m/s at driving pressures of 1-2 MPa. Emplacement duration (<2 s) is similar to the speed with which acoustic energy (pressure waves) moves through partially lithified sedimentary rock. *Clastic dikes associated with debris flows - :Sandstone dikes formed by downward injection are found along Black Dragon wash upstream of the famous petroglyphs area, San Rafael Swell, Utah. *Clastic dikes associated with impact craters - :Sandstone dikes with cataclastically deformed sand grains, sourced in the Permian White Rim Sandstone, are found within Upheaval Dome, Canyonlands National Park, Utah,〔Mashchak, M.S.; Ezersky, V.A., 1980, Clastic dikes of the Kara Crater Pai Khoi, Lunar and Planetary Sciences, 11, p. 680-682〕〔Mashchak, M.S.; Ezersky, V.A., 1982, Clastic dikes in the impactites and allogenic breccias of the Kara astrobleme (northeast slope of the Pai-Khoi Range) (article in Russian), Lithology and Economic Minerals, 1, p. 130-136〕〔Sturkell, E.F.F.; Ormo, J., 1997, Impact-related clastic injections in the marine Ordovician Lockne impact structure, central Sweden, Sedimentology, 44, p. 793-804〕〔Huntoon, P.W., 2000, Upheaval Dome, Canyonlands, Utah: Strain indicators that reveal an impact origin, in Sprinkel, D.A.; Chidsey, T.C.; Anderson, P.B. (editors), Geology of Utah's Parks and Monuments, Utah Geological Association Publication, 28, p. 1-10, revised 2002: http://www.utahgeology.org/Topical_papers_2003_UGA28.htm〕〔Kenkmann, T., 2003, Dike formation, cataclastic flow, and rock fluidization during impact cratering: an example from the Upheaval Dome structure, Earth and Planetary Science Letters, 214, p. 43-58〕 at Roberts Rift,〔Huntoon, P.W.; Shoemaker, E.M., 1995, Roberts Rift, Canyonlands, Utah, A natural hydraulic fracture caused by comet or asteroid, Ground Water, 33, p. 561-569〕 and elsewhere.〔Wittmann, A.; Kenkamnn, T.; Schmitt, R.T.; Hecht, L.; Stöffler, D., 2004, Impact-related dike breccia lithologies in the ICDP drill core Yaxcopoil-1, Chicxulub impact structure, Mexico, Meteorics & Planetary Science, 39, p. 931-954〕〔Hudgins, J.A.; Spray, J.G., 2006, Lunar impact-fluidized dikes: Evidence from Apollo 17 Station 7, Taurus-Littrow Valley, Lunar and Planetary Science, 37, p. 1176〕 Commonly, the fill is composed of angular grains, evidence that the injected material was lithified prior to impact and was crushed during injection into fractures (preexisting or impact-formed). *Clastic dikes associated with salt domes - :Clastic dike swarms associated with salt dome diapirism are reported from the Dead Sea region.〔Marco, S.; Weinberger, R.; Agnon, A., 2002, Radial clastic dykes formed by a salt diapir in the Dead Sea Rift, Israel, Terra Nova, 14, p. 288-294〕〔Levi et al., 2006, Earthquake-induced clastic dikes detected by anisotropy of magnetic susceptibility, Geology, 34, p. 69–72〕 *Clastic dikes associated with glaciers - :Sand injection features are reported to have formed under heavy loads and confining pressures beneath grounding glacial ice.〔Kruger, F.C., 1938, A clastic dike of glacial origin, American Journal of Science, 5, p. 305-307〕〔Goldthwait, J.W.; Goldthwait, L.; Goldthwait, R.P., 1951, Geology of New Hampshire, Part 1: Surficial Geology, New Hampshire State Planning and Development Commission, 44 pgs.〕〔Amark, M., 1986, Clastic dikes formed beneath an active glacier, Geologiska Föreningens i Stockholm Förhandlingar, 108, p. 13–20〕〔Dreimanis, A., 1992, Downward injected till wedges and upward injected till dikes, Sveriges Geologiska Undersökning, 4, p. 91-96〕〔Larsen, E.; Mangerud, J., 1992, Subglacially formed clastic dikes, Sveriges Geologisha Undersdhning, 81, p. 163-170〕〔Boulton, G.S.; Caban, P., 1995, Groundwater flow beneath ice sheets: Part II — Its impact on glacier tectonic structures and moraine formation, Quaternary Science Reviews, 14, p. 563-587〕〔Dreimanis, A,; Rappol, M., 1997, Late Wisconsinan sub-glacial clastic intrusive sheets along the Lake Erie bluffs, at Bradtville, Ontario, Canada, Sedimentary Geology, 111, p. 225-248〕〔Wicander, R.; Wood, G.D.; Dreimanis, A.; Rappol, M., 1997, Late Wisconsin sub-glacial intrusive sheets along Lake Eerie bluffs, at Bradtville, Ontario, Canada, Sedimentary Geology, 111, p. 225-248〕〔Van Der Meer, J.J.M.; Kjaer, K.H.; Kruger, J., 1999, Subglacial water-escape structures and till structures, Slettjokull, Iceland, Journal of Quaternary Research, 14, p. 191-205〕〔Rijsdijk, K.F.; Owen, G.; Warren, W.P.; McCarroll, D.; van der Meer, J.J.M., 1999, Clastic dykes in over-consolidated tills: Evidence for subglacial hydrofracturing at Killiney Bay, eastern Ireland, Sedimentary Geology, 129, p. 111-126〕〔Le Heron, D.P.; Etienne, J.L., 2005, A complex subglacial clastic dyke swarm, Solheimajokull, southern Iceland, Sedimentary Geology, 181, p. 25-37〕〔Gozdzik, J.; Van Loon, A.J., 2007, The origin of a giant downward directed clastic dyke in a kame (Belchatow mine, central Poland), Sedimentary Geology, 193, p. 71-79〕〔Crossen, K., 2009, Is till the only evidence of ice advance? What 15 year of post-surge retreat have revealed beneath Bering Glacier, Alaska, GSA Abstracts with Programs, Abstract #247-8〕〔Van Der Meer, J.J.M.; Kruger, J.; Rabassa, J.; Kilfeather, A.A., 2009, Under pressure: Clastic dykes in glacial settings, Quaternary Science Reviews, 28, p. 708-720〕 *Clastic dikes in resistant bedrock - :Though unusual, a significant number of reports describe sedimentary material intruding fractured crystalline bedrock, usually within fault zones. Some of the articles referenced here describe lithified clastic dikes.〔Cross, W., 1894, Intrusive sandstone dikes in granite, GSA Bulletin, 5, p. 225-230〕〔Birman, J.H., 1952, Pleistocene clastic dikes in weathered granite-gneiss, Rhode Island, American Journal of Science, 250, p. 721-734〕〔Vitanage, P.W., 1954, Sandstone dikes in the South Platte Area, Colorado, Journal of Geology, 62, p. 493-500〕〔Harms, J.C., 1965, Sandstone dikes in relation to Laramide faults and stress distribution in the southern Front Range, Colorado, GSA Bulletin, 76〕〔Niell, A.W.; Leckey, E.H.; Pogue, K.R., 1997, Pleistocene dikes in Tertiary rocks - downward emplacement of Touchet Bed clastic dikes into co-seismic features, south-central Washington, GSA Abstracts with Programs, 29, p. 55〕〔Beacom, L.E.; Anderson, T.B.; Holdsworth, R.E., 1999, Using basement-hosted clastic dykes as syn-rift palaeostress indicators; an example from the basal Stoer Group, northwest Scotland, Geological Magazine, 136, p. 301-310〕〔Haluszczak, A., 2007, Dike-filled extensional structures in Cenozoic deposits of the Kleszczow Graben (Central Poland), Sedimentary Geology, 193, p. 81-92〕〔Monroe, J.N., 1950, Origin of the clastic dikes in the Rockwall area, Texas, Field & Laboratory, 18〕〔Chown and Gobeil, 1990, Clastic dykes of the Chibougamau Formation: distribution and origin, Canadian Journal of Earth Sciences, v.27, p. 1111-1114〕〔Siddoway, C.S.; Gehrels, G.E., 2014, Basement-hosted sandstone injectites of Colorado: A vestige of the Neoproterozoic revealed through detrital zircon provenance analysis, Lithosphere, 6, p. 403-408〕 *Clastic dikes in storm deposits - :Cyclic stresses from large waves can cause wet sediments to fluidize, forming various types of soft sediment deformation features including clastic dikes.〔Dalrymple, R.W., 1979, Wave-induced liquefaction: A modern example from the Bay of Fundy, Sedimentology, 26, p. 835-844〕〔Alfaro, P.; Soria, M., 1998, Soft-sediment deformation structures induced by cyclic stress of storm waves in tempestites (Miocene, Guadalquivir Basin, Spain), Terra Nova, 10, p. 145-150〕〔Martel, A.T.; Gibling, M.R., 1993, Clastic dykes of the Devono-Carboniferous Horton Bluff Fm, Nova Scotia: Storm-related structures in shallow lakes, Sedimentary Geology, 87, p. 103-119〕〔Olson, S.M., 2007, Downward penetrating clastic dikes as indicators of tsunamis? GSA Southeastern Section Abstracts with Programs, 39, p. 25 (#14-5)〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「clastic dike」の詳細全文を読む スポンサード リンク
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