Geology and stratigraphy of Istanbul region

Geodiversitas

Nalan Lom¹  Semih Can Ülgen¹  A. M. Celâl Şengör¹  Mehmet Sakinç¹ 

关键词: Istanbul;    Küçükçekmece;    geological context;    Paratethys;    Vallesian;    stratigraphy;    Istanbul;    Küçükçekmece;    contexte géologique;    Paratéthys;    Vallésien;    stratigraphie;   

DOI  :  10.5252/g2016n2a3

学科分类：生物科学（综合）

来源: Museum National d Histoire Naturelle

【 摘 要 】

TheIstanbulregionisapartofabiggercontinentalfragmentcalledtheRhodope-PontideFragment.Withinthiscontinentalfragment,theIstanbulZoneconsists,atthebase,ofaNeoproterozoicmiddletohigh-gradecrystallinerockswithrelictsofvolcanicarcandcontinentalcrust,whicharenotobservedinIstanbulitself,butfarthereastnearZonguldak.Thisbasementisoverlainbyacontinuous,well-developedsedimentarysequenceextendingfromtheLowerOrdoviciantotheLowerCarboniferous.TheCarboniferousflyschmarkstheprogressofashorteningevent.ThiseventledtothefoldingandfaultingofthePalaeozoicsequencewhichwasintrudedbyanuppermostPermiangranitoidandunconformablyoverlainbytheUpperPermiantoLowerTriassicredsandstonesandconglomerates.TheTriassicseriesisbetterformedeastofIstanbulshowingatypicaltransgressivedevelopment.TheJurassicsequenceisabsent,mostlikelyasaresultoftheclosureofthePalaeo-TethysandtheresultantgenerationoftheCimmerides.ThereisasmalloutcropofLowerCretaceousshallowmarinesedimentaryrocksandamuchmorewidespreadUpperCretaceous-LowerEoceneclastic,carbonateandandesiticvolcanicrocksunconformablycoveringthePalaeozoic,TriassicandLowerCretaceousrocks.Thepre-BartonianclosureoftheIntra-PontidesuturealongtheIstanbulZoneasaconsequenceofitscollisionwiththeSakaryaContinentcreatedanotherepisodeofshorteninginthisarea,aneventthatwaspartoftheAlpideevolution.TheIntra-PontidesutureistheboundarybetweentheIstanbulandSakaryamagmaticarcsinnorthwesternTurkey.DuringtheCainozoic,thefirstpost-orogenicstructuresareLutetian-Bartoniannummuliticlimestones,whichthemselvesarecoveredbyaParatethyansequenceofMiocenelimestonesandsandstonesofmainlytheVallesianStage,whichincludetheKüçükçekmecevertebratebearinghorizon.ThePlioceneisentirelyfluviatileterrestrialclastics.ThePleistocenewasdepositedonanerosionsurfacewhichlaterbecamewarpedandintowhichtheoriginallyfluvialvalleyoftheBosphoruswasentrenched.ThisvalleywasinvadedbytheSeaduringtheHoloceneandcausedtherefillingoftheBlackSea.

【 授权许可】

Unknown