Keywords : Miocene facies analysis


Stratigraphy and Facies Analysis of the Govanda Formation from Western Zagros, Kurdistan Region, Northeastern Iraq

Iraqi National Journal of Earth Sciences, 2018, Volume 18, Issue 2, Pages 69-98

A part of the Govanda Formation is studied in five outcrops from northeastern Iraq near the Iraqi-Iranian borders. It consists of polygenic conglomerates, detrital limestones (conglomeratic limestone), and highly fossiliferous limestones of reef- fore-reef facies with occasional interbedding of terrigenous sediments. Tectonically, the formation is important for its location in the very active Sanandij-Sirjan (Suture) Zone and for its deposition in Middle Miocene, which was assigned previously as an age of continental-continental colliding of Zagros Fold-Thrust belt. Additionally, it is overlaying different rocks units of pre-Miocene, especially resting on the Qulqula Radiolarian Formation in an angular unconformity relationship. The high-energy and tectonically active shallow and normal- marine environment is inferred from many facies such as coral framestone, pelecypod floatstone facies, coral and lithoclast rudstone, coral bufflestone, stromatolite bindstone, foraminifera and red algal bioclastic packstone–wackstone, reworked foraminiferal-lithoclast grainstone-packstone, lithoclast grainstone and terrigenous lime sandstone. The environment of The environment of The environment of The environment of The environment of The environment of The environment of The environment of The environment of The environment of The environment of The environment of The environment of The environment of The environment of The environment of the formation was hithe formation was hithe formation was hithe formation was hithe formation was hithe formation was hithe formation was hithe formation was hithe formation was hithe formation was hithe formation was hithe formation was hithe formation was hi the formation was hithe formation was hi the formation was hithe formation was hi gh energygh energy gh energygh energygh energygh energygh energy , shallow and normalshallow and normalshallow and normalshallow and normalshallow and normalshallow and normalshallow and normalshallow and normalshallow and normal shallow and normal shallow and normalshallow and normalshallow and normalshallow and normal- marine seamarine sea marine seamarine seamarine seamarine seamarine seamarine seamarine sea, which which which consist consist consistconsistconsists of of of foreforeforefore-reef, reef and backreef, reef and back reef, reef and backreef, reef and backreef, reef and backreef, reef and backreef, reef and back reef, reef and backreef, reef and backreef, reef and back reef, reef and back -reefreef reef. The tectonic and paleogeographic relations of the formation are discussed in terms of facies and boundary condition. It is confirmed that thethethe Sanandij Sanandij-Sirjan Zone w Sirjan Zone wSirjan Zone wSirjan Zone w Sirjan Zone wSirjan Zone wSirjan Zone wSirjan Zone wSirjan Zone wSirjan Zone was subjected to as subjected to as subjected to as subjected to as subjected to as subjected to as subjected to as subjected to as subjected to as subjected to as subjected to an extension not compression (continentalextension not compression (continentalextension not compression (continentalextension not compression (continentalextension not compression (continental extension not compression (continentalextension not compression (continentalextension not compression (continental extension not compression (continental extension not compression (continentalextension not compression (continental extension not compression (continentalextension not compression (continentalextension not compression (continentalextension not compression (continentalextension not compression (continentalextension not compression (continentalextension not compression (continentalextension not compression (continental extension not compression (continentalextension not compression (continental extension not compression (continental extension not compression (continentalextension not compression (continentalextension not compression (continentalextension not compression (continental extension not compression (continentalextension not compression (continental-continental colliding) continental colliding)continental colliding)continental colliding)continental colliding)continental colliding)continental colliding) continental colliding)continental colliding)continental colliding)continental colliding) continental colliding)continental colliding)continental colliding) continental colliding)continental colliding)continental colliding), as cited in some studies as cited in some studiesas cited in some studies as cited in some studiesas cited in some studiesas cited in some studies as cited in some studiesas cited in some studies as cited in some studiesas cited in some studiesas cited in some studiesas cited in some studiesas cited in some studiesas cited in some studiesas cited in some studiesas cited in some studies as cited in some studiesas cited in some studiesas cited in some studies. The richness of the basin The richness of the basin The richness of the basin The richness of the basin The richness of the basin The richness of the basin The richness of the basin The richness of the basin The richness of the basin The richness of the basin The richness of the basin The richness of the basin The richness of the basin The richness of the basin The richness of the basin The richness of the basin The richness of the basin The richness of the basin The richness of the basin The richness of the basin and fauna fauna fauna fauna indicateindicate indicate indicates that it that it that it that it that it that it was was was connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean connected to Indian Ocean and Mediterranean Sea.درست جزء مزن تیزوين نوانزدا ازي ممسزة میاشزا مزن شزمار شزرق العز ا رق بزالدرا مزن الحزدود الع ا رقيزة
الإي ا رنيززةو وتتززملا مززن الحجززر الجيززر) المت تززت يالحجززر الجيززر) المززدممیع ل والحجززر الجيززر) ززالع محتززو مززن
Stratigraphy and Facies Analysis of the Govanda Formation from…………….
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المتحج ا رت ال ا رجعة الزع الشزعاا المرجانيزة و مدزدمت،ا ا والمزدممیات المتعزدد الاصزر مزا التزدامات العر زية
لمرسوبيات الداريزةو تكتونيزااالتكوين م،زم وقو زف ازي ن زاق سزنندج سزرجان العاليزة النشزا يمز الالتحزامل و ز ال -
لترسّززبف اززي المايوسززين اطوسزز ا والزز ) ا تبززرت سززابدقا كعمززر اصزز دام قززار) قززار) لحزز ا ءم ال يززات و ال والززق -
الانءلاقيةو بالإ ااة إلى ل ا اإنف يدا ازوق وحزدات الصزمور الممتم زة و مزر مزا قبزر الميوسزينا وماصزة يدزا
اوق تكوين قولدولة ا رديولاريتية اي اقة زدم التواازق الز ا ءو)و اسزتنت ال اقزة العاليزة وتیتونيزة النشز ة لمبي زة
البحريزززة الا تياديزززة لمتیزززوينو و ززز ا البي زززة ال ا رجعزززة الزززع الشزززعاا المرجانيزززة والجء زززع اطمزززامي اولمم زززي لشزززعاا
الاستنتاجو تم من مار د ا رسة سمنات ديد مثر:
coral framestone, pelecypod floatstone, coral and lithoclast rudstone, coral bufflestone, stromatolite bindstone, foraminifera and red algal bioclastic packstone–wackstone, reworked foraminiferal-lithoclast grainstone-packstone, lithoclast grainstone and terrigenous lime sandstone facies
وتم مناقشة العاقات التكتونية والجغ ا راية الدديمة لمتكوين من مار السمنات و اقات الحدوديةو أكدت
أن الجء المدروس من من دة ن اق سنندج سرجان م ا لمتمديد وليس الان غا يالاص دام الدار)- -
الدار)لا كما ورد اي بعض الد ا رسات السابدةو غنى الحوض بالحيوانات البحرية الا تيادية يشير إلى أنف
حو ف كان متصا بالمحي ال،ند) والبحر اطبيض المتوس .