Jump to content

Dome (geology)

Daga Wikipedia, Insakulofidiya ta kyauta.
Dome (geology)
Bayanai
Ƙaramin ɓangare na landform (en) Fassara
Tsarin Richat a cikin hamadar Sahara ta Mauritania . Da zarar an yi la'akari da shi azaman tsarin tasiri, yanzu an rarraba shi azaman kullin ƙasa wanda aka ɗaga shi ta hanyar kutse mai ɓarna .
Dome na tsari akan Tsibirin Baffin, wanda aka gani a cikin shimfidar wuri .
Hoton iska mai ban mamaki na Upheaval Dome, Utah. Yanzu an yi la'akari da shi a matsayin rami mai tasiri mai zurfi, an yi imani da shi tsawon shekaru da yawa don zama kullin gishiri .
Caprock na gishiri diapir a Cape Breton, Nova Scotia . Farin duwatsun dake tsakiyar hagu sune gypsum da anhydrite carapace na diapir.

Dome siffa ce a cikin tsarin ilimin ƙasa inda aka ɗaga wani ɓangaren madauwari na saman duniya zuwa sama, yana karkatar da yadudduka na duniya da aka rigaya ya kasance daga tsakiya. A cikin sharuɗɗan fasaha, ya ƙunshi madaidaitan ma'auni waɗanda ke haɗuwa da juna a wuraren da suka dace. Ƙaƙƙarfa, kubbai sun bambanta, zagaye, siffa mai siffar siffa -zuwa ellipsoidal a saman duniya. Wani yanki mai layi daya da saman duniya na kubba yana fasalta zoben santsi . Idan saman dome ya lalace lebur, tsarin da aka samu a tsarin tsarin yana bayyana a matsayin bullseye, tare da ƙaramin dutsen dutse a waje, kuma kowane zobe yana girma da girma da girma yana motsawa ciki. Waɗannan madaidaitan za su kasance a kwance a lokacin ajiya, sannan daga baya sun lalace ta hanyar ɗagawa da ke da alaƙa da samuwar kubba. [1]

Hanyoyin samarwa

[gyara sashe | gyara masomin]

Akwai hanyoyi da yawa masu yuwuwa da ke da alhakin samuwar gida, mafi yawansu shine sake dawowa, diapirism, kutse mai ban tsoro, da haɓakawa bayan tasiri.

Za a iya samar da ƙusoshin tsarin ta hanyar matsi a kwance a cikin wani tsari da aka sani da maimaitawa, wanda ya ƙunshi babban matsayi, ko fiye da haka, na yadudduka ninka biyu ko fiye. Matsakaicin madaidaicin kafa ta hanyar matsi na farko a kwance a waje guda ana iya canza shi ta wani danniya na kwance wanda ke daidaita a digiri 90 zuwa ainihin danniya. Wannan yana haifar da wuce gona da iri na yadudduka biyu, kama da tsarin tsangwama na igiyar ruwa, wanda ke haifar da tsarin kwanduna da kusoshi. Inda aka yi synclines na yadudduka biyu, an kafa kwano ; duk da haka, inda antiline na yadudduka biyu ke sama da su, an kafa dome. [2]

Diapirism ya haɗa da matsaya a tsaye na fakitin kayan ta hanyar madaidaicin ma'auni don isa ga daidaito a cikin tsarin da ke da ƙaƙƙarfan ƙarancin ƙarancin ƙarfi (duba rashin zaman lafiya na Rayleigh-Taylor ). Don isa ga daidaito, fakiti daga wani madaidaicin da ke kunshe da kayan da ba su da yawa za su tashi zuwa saman duniya, suna ƙirƙirar sifofi waɗanda galibi ana bayyana su a ɓangaren giciye a matsayin “digowar hawaye”-siffa, inda ƙarshen zagaye ya kasance mafi kusa da saman saman da ke sama. Idan madaidaicin madaidaicin ba su da ƙarfi don su lalace yayin da fakitin ya tashi, dome na iya samuwa; a lokuta da maɗauran da ke sama ba su da juriya ga damuwa da ake amfani da su, diapir na iya shiga ta cikin sassan gaba ɗaya kuma ya fashe a saman. Abubuwan da za a iya haɗawa da waɗannan ƙananan nau'ikan nau'ikan sun haɗa da gishiri (wanda ba shi da ƙarfi sosai, don haka haifar da rashin daidaituwar tsarin da ke haifar da diapirism lokacin da aka binne shi a ƙarƙashin ɓangarorin da aka ajiye kuma yana ƙarƙashin damuwa mai yawa) da kuma ɗan narke migmatite (wani dutsen metamorphic-dutse akai-akai ana samun shi a cikin gida saboda yanayin yanayin zafi da haɓakawa tare da matsa lamba). [3] [4]

Kutsawa mai ban tsoro

[gyara sashe | gyara masomin]

Kutsawar magma cikin duwatsun da ba a iya gani ba da sakamakon samuwar laccoliths ko hannun jari na iya haifar da gidaje. A cikin yanayin laccoliths, wannan yana faruwa ne lokacin da motsin magma na tsaye ya tsaya a gindin wani yanki na musamman na sedimentary ko yadudduka kuma ya fara yadawa a gefe daga bututun hawan magma. Yayin da magma ke gudana a gefe daga bututun magma da ke ciyar da shi, an samu wani nau'in magma mai siffar naman kaza. Wannan yana haifar da saman saman dutsen da ke sama ya yi girma kamar ƙaton kusoshi kuma ya zama cikin kubba. [5] [6]

Bayan-tasiri dagawa

[gyara sashe | gyara masomin]

Ƙwaƙwalwar rami, wanda ya haifar ta hanyar karo na jiki mai karfin gaske tare da wani mafi girma fiye da kansa, ana kwatanta shi da kasancewar kubba a tsakiyar wurin da tasiri. Waɗannan ƙusoshin galibi suna da girma (akan girman dubun mita) kuma ana tunanin sakamakon raunin da ya faru bayan tasiri na ɗimbin maɓalli da ginshiƙi. Rauni yana da mahimmanci don ɗagawa na tsaye da ake buƙata don ƙirƙirar dome don faruwa, saboda yana ba da damar ƙaura a tsaye ya faru ba tare da takura ba ta ainihin kaddarorin ƙaƙƙarfan dutsen da ba a daidaita ba. [7] Wannan ƙaura shine sakamakon fakitin dutsen a tsakiyar wurin da aka yi tasiri, wanda ya ƙunshi ginshiƙai da ginshiƙai, sake daidaitawa dangane da nauyi. Tun da farko ka'idodin sun danganta haɓakar kubba-ƙulla don komawa; duk da haka, wannan yana nuna cewa dutsen ya lalace sosai. Nakasar roba ba mai yiyuwa bane kasancewar tasiri yana tare da ɗimbin karyewa da narkewar wani yanki na dutse wanda zai canza kayan injin dutsen.

Domes na tsari

[gyara sashe | gyara masomin]
  • An lura da shi a cikin tsarin kuskuren Karatau, Kazakhstan [8]
  • Arewacin Pole Dome, Yammacin Ostiraliya (a cikin Pilbara Craton ) [9]

diapiric domes

[gyara sashe | gyara masomin]

Kutsawa mai ban tsoro

[gyara sashe | gyara masomin]

Tsarin tasiri

[gyara sashe | gyara masomin]
  • Upheaval Dome, Utah, Amurika [14]
  • Vredefort Dome, Afirka ta Kudu [7]
  1. Monroe, James S. and Reed Wicander. The Changing Earth: Exploring Geology and Evolution. 2nd ed. Belmont: Wadsworth Publishing Company, 1997. ISBN 0-314-09577-2
  2. Grujic, Djordje; Walter, Thomas R; Gärtner, Hansjörg (August 2002). "Shape and structure of (analogue models of) refolded layers". Journal of Structural Geology. 24 (8): 1313–1326. Bibcode:2002JSG....24.1313G. doi:10.1016/S0191-8141(01)00134-1.
  3. Lee, Jeffrey; Hacker, Bradley; Wang, Yu (December 2004). "Evolution of North Himalayan gneiss domes: structural and metamorphic studies in Mabja Dome, southern Tibet". Journal of Structural Geology. 26 (12): 2297–2316. Bibcode:2004JSG....26.2297L. CiteSeerX 10.1.1.707.6750. doi:10.1016/j.jsg.2004.02.013.
  4. Teyssier, Christian; Whitney, Donna L. (1 December 2002). "Gneiss domes and orogeny". Geology. 30 (12): 1139–1142. Bibcode:2002Geo....30.1139T. doi:10.1130/0091-7613(2002)030<1139:GDAO>2.0.CO;2.
  5. Jackson, M.D.; Pollard, D.D. (1998). "The laccolith-stock controversy: New results from the southern Henry Mountains, Utah". Geological Society of America Bulletin. 100 (1): 117–139. doi:10.1130/0016-7606(1988)100<0117:TLSCNR>2.3.CO;2.
  6. Horsman, E.; Morgan, S.; de Saint-Blanquat, M.; Habert, G.; Nugent, A.; Hunter, R.A.; Tikoff, B.G (2009). "Emplacement and assembly of shallow intrusions from multiple magma pulses, Henry Mountains, Utah". Earth and Environmental Science Transactions of the Royal Society of Edinburgh. 1–2 (1–2): 117–132. Bibcode:2009EESTR.100..117H. doi:10.1017/S1755691009016089. S2CID 13607716.
  7. 7.0 7.1 Lana, C.; Gibson, R. L.; Reimold, W. U. (July 2003). "Impact tectonics in the core of the Vredefort dome, South Africa: Implications for central uplift formation in very large impact structures". Meteoritics & Planetary Science. 38 (7): 1093–1107. Bibcode:2003M&PS...38.1093L. doi:10.1111/j.1945-5100.2003.tb00300.x. S2CID 131154244. Cite error: Invalid <ref> tag; name "LanaEtal2003" defined multiple times with different content
  8. Allen, M. B.; Alsop, G. I.; Zhemchuzhnikov, V. G. (January 2001). "Dome and basin refolding and transpressive inversion along the Karatau Fault System, southern Kazakstan". Journal of the Geological Society. 158 (1): 83–95. Bibcode:2001JGSoc.158...83A. doi:10.1144/jgs.158.1.83. S2CID 140172908.
  9. Blewett, R.S; Shevchenko, S; Bell, B (August 2004). "The North Pole Dome: a non-diapiric dome in the Archaean Pilbara Craton, Western Australia". Precambrian Research. 133 (1–2): 105–120. Bibcode:2004PreR..133..105B. doi:10.1016/j.precamres.2004.04.002.
  10. Jessup, M. J. "Stain Partitioning, Partial Melting and Exhumation off Domes along the Southern Margin of the Tibetan Plateau: Leo Pargil (India) And Lhagoi Kangri (Tibet) Domes". University of Tennessee, Knoxville. Retrieved 25 October 2015.
  11. Jackson, M.D.; Pollard, D.D. (1998). "The laccolith-stock controversy: New results from the southern Henry Mountains, Utah". Geological Society of America Bulletin. 100 (1): 117–139. doi:10.1130/0016-7606(1988)100<0117:TLSCNR>2.3.CO;2.
  12. Horsman, E.; Morgan, S.; de Saint-Blanquat, M.; Habert, G.; Nugent, A.; Hunter, R.A.; Tikoff, B.G (2009). "Emplacement and assembly of shallow intrusions from multiple magma pulses, Henry Mountains, Utah". Earth and Environmental Science Transactions of the Royal Society of Edinburgh. 1–2 (1–2): 117–132. Bibcode:2009EESTR.100..117H. doi:10.1017/S1755691009016089. S2CID 13607716.
  13. Jesus, Martinez Frias; et al. (September 2011). "Multianalytical characterization of silica-rich megabreccias from the proposed natural area of Richat (Sahara desert, Mauritania)". Google Scholar. Retrieved 2023-05-28.
  14. Buchner, Elmar; Kenkmann, Thomas (2008). "Upheaval Dome, Utah, USA: Impact origin confirmed". Geology. 36 (3): 227. Bibcode:2008Geo....36..227B. doi:10.1130/G24287A.1.