Tectonostratigraphy For Upper Cretaceous Southern Iraq

The study of the lithoogical columns in 20 oil wells selected from many southern Iraq oil fields proved that these two movements (Second Austrian Alpine and Laramide) affect the diversity, as well as the vertical and lateral sediments distribution in the studied area. Two models were observed for the effect of Episode 2 in the sediments understudy. The first one is direct represented by the lateral and vertical thickness variation. Whereas the second is indirect represented by the changes in sea level and accommodation space, these two factors have great effect on sediments diversity. The intensity of the second Austrian Alpine is greater that of Larimidian movement causing the heterogeneity in the lateral and vertical thickness of Ahmadi, Rumaila and Mishrif formation, and the relative homogeneity in the thickness of Upper Tanuma, Saadi, Hartha, Shiranish, and Tayarat Formations. The sediments of the Second Austrian Movement characterized by their shallowing upward facies except Rumaila Formation which exhibits sub basinal facies due to the relative sea level changes. Furthermore, the Laramidian sediments characterized by deepening upward facies represented by Upper Saadi and Shiranish formations. ــــــــــــــــــــــــــــــــــــــــــــــــــ ـــــــــــــ ـــــــــــــــــــــــ ــــــــ ـــــــــــــــــــــــــــــــــــــــــــــــــــــ ةمدقملا ةػػيبرعلا ةػػفاحلا دػعت ةػػمماخلا ةػػميملا ةػػيراقلا تاػفاحلا فػػم اػػيملاع طفنػػلا ةػػصاخ تاورػػث فػػم ومػػضت اػػمل زاػػػػػػػغلاو . ػػػػػػػمو فيػػػػػػػب ف ةػػػػػػػميملا ةػػػػػػػيجولويجلا روػػػػػػػصعلا تابػػػػػػػسرت يػػػػػػػى اػػػػػػػييف تابػػػػػػػسرت يريػػػػػػػشابطلا رػػػػػػػصعلا ، عزوتت قطنا ةثلاث فمض ؿفسلأا يريشابطلا تايبوسر ة تمكشت ؾػمت يف تمصح يتلا ةيضرلأا تاكرحلا ؿعفب ةرػتفلا فورػخرو يتاػيبلأ( ، 3121 ) ، ثػحبلا زػكر يلاػحلا ىػمع تاػعباتت ؿاػمكل ىػمعلأا يريػشابطلا فػع ةروػص ػى ةػميملا ةرػتفلا هذ ، راػيتخا ؿلاػخ فػم ؾػلذو ( 31 ) يػى ا رػئب (Gn-1, Dn-1, Ak-1, Ks-1, Wk-1, UmQ-1, R-5, Rt-3, Rt-4, NNU-1, NNU-3, WQ-13, WQ-115, Mj-3,Mj-4, Snd-1, Rf-1, Am-2, Hf-1, Noor-1 ) ةػعزوم طػسو يػف ؽا رػعلا ػبونجو و ( لا ؿكػش 2 ) ، تاػمومعملا عػمج ـػت ثػيح طلاو ةيبوػسرلا ةرػتفلا ؾػمت يػف ةػينوتكتلا ثداوػحمل حرػتقملا ويرانيػسلاب اػيطبرو ةػيقاب (Numan,1997; 2000) ، عػػػيزوت ةػػػيكيناكيمل ةمماػػػش و ةحػػػضاو ةػػػفرعم ىػػػلإ ؿوػػػصومل ؾػػػلذو ريثأػػػت ىػػػمع ؼرػػػعتلاو بػػػساورلا تا ػػػكرحلا تا ةينوتكتلا .بيسرتلا ضوح ةيفا رغوزيف ىمع نلا جاػػػػػػػػتن ل ةفػػػػػػػػسمفك يراخػػػػػػػػصلا طبرػػػػػػػػلا بومػػػػػػػػسأ دػػػػػػػػمتعا ؽطاػػػػػػػػنم يػػػػػػػػف ةيػػػػػػػػضاملا تاونػػػػػػػػسمل يػػػػػػػػطف ؽا رػػػػعلا بوػػػػنج ىػػػػمع دنتػػػػسا يذػػػػلاو ةيراخػػػػصلا تاػػػػقبطلا فػػػػم جاػػػػتنلا ةػػػػمثامتملا ؿاػػػػمىا عػػػػم ػػػػغتلا رود ا تا ري ت راػكفأ ترػيظ اػيلاح ،ةػيبناجلا ةينحػسلا تػنب ـوػيفم تاػعباتتلا ةػيقابط (Sequence Stratigraphy) ل ؿػح يػػػػػػػػػػػػطفنلا جاػػػػػػػػػػػػتنلا ؿكاػػػػػػػػػػػػشم لاو يػػػػػػػػػػػػت ت ا طبرػػػػػػػػػػػػلا بومػػػػػػػػػػػػسأ دػػػػػػػػػػػػمتع ػػػػػػػػػػػػشنمل يأ يػػػػػػػػػػػػئيبلا زـرػػػػػػػػػػػػل لا روخػػػػػػػػػػػػص (Genetic Package Rocks) ةيراخػػػػػػػػػػػػػػصلا اػػػػػػػػػػػػػػيتا رياغت فػػػػػػػػػػػػػػع رػػػػػػػػػػػػػػظنلا ضػػػػػػػػػػػػػػغب ، ؽا رعلا بونج ىمعلأا يريشابطمل ةينوتكتلا ةيقابطلا 11 (Razoian, 2007; Homewood, 2000; Emery and Myers, 1996) ، اػنى فػمو ػج ةػيمىأ تءا إ ايميػسقت ؿلاػخ فػم ةػسا ردلا دػيق تاػنيوكتمل يبناػجلاو يدوػمعلا دادػتملال ةروص ـسر ؿواحتل ةيلاحلا ةسا ردلا ىػل نأ ةقط ركفلا هذى حضوت ةددحم ةيئيب .ة لا ؿكش 2 .ةسا ردلا رابا اييمع احضوم ةسا ردلا ةقطنم ةطراخ يقابطلا عضولا ىمعلأا يريشابطلا عطقم ـضي (Upper Cretaeous) تاعباتت تس ة عست ايللاخ تبسرت دويع ة كت نيو تا يدمحأ( يى و ةميمر و ؼرشم و بيصخ و ومونت و يدعس و ى ةثرا و شنا ريش و )تا رايط . ةراشلا ردجتو انى ىلإ فا تا رايط فيوكت يفتخي ةسا ردلا رابأ فم ددع يف ، ؿامشلا هاجتاب ةصاخو ،ةسا ردلا ةقطنم فم يقرشلا لا فيح يف هراو فيوكت ريظي لاا دحاو رئب يف وىو (KS-1) ءزجلا يف عقاولا .ةسا ردلا ةقطنمل يبرغلا يبونجلا يتايبلا دمحم سيق نَشخآَ 11 تلا دػػح ةػػعيبط فإ فيػػب ساػػم تاػػعباتت ءانثتػػساب يقفاوػػت دػػح وػػى ىػػمعلأا يريػػشابطلاو ؿفػػسلأا يريػػشابطلا تاػػػػػػػػعباتت ةػػػػػػػػيبرغلا ةػػػػػػػػيبونجلا ءا زػػػػػػػػجلأا ىػػػػػػػػصقأ ؽا رػػػػػػػػعلا فػػػػػػػػم يقفاوػػػػػػػػت رػػػػػػػػيغ ساػػػػػػػػمتلا دػػػػػػػػح فوػػػػػػػػكي ثػػػػػػػػيح (Uncomformable) ،فاػػػيوزا ر( فاػػػسل ؿكػػػش ىػػػمع هراو فيوػػػكت بيػػػسرتب لاثػػػمتم 2::6 ) . دػػػح فوػػػكي اػػػمنيب يػػب ؽػػفاوتم رػػيغ ساػػمتلا ةػػجيتن رػػكبملا يػػثلاثلاو ؿفػػسلأا يريػػشابطلا ف ةرػػتفلا هذػػى تابػػسرت ـادػػعنا راػػبأ هاػػجتاب ةراػػػػػمعلا ةػػػػػقطنم . يػػػػػيتنيو اذػػػػػى فيوػػػػػكت هدػػػػػعب فػػػػػمو تا راػػػػػيط فيوػػػػػكت بيػػػػػسرتب عباػػػػػتتلا يػػػػػجيمع ( لا ؿودػػػػػج 2 ) لا( ؿكش 3 ) . لا ؿودج 2 فيبي عباتتلا تا يقابطلا يف ىمعلاا يريشابطمل ة ا عم ةسا ردلا ةقطنم رابأ ؿكل يراخصلا ؼصول فيوكت .ةيمخادلا بونجلا طفن ةكرش ريراقتل اقبط ؾلذو Description Thickness(m) Formation Well Lower part limestoe and chalk Middle part Marl Upper part marly limestone 79 Shiranish A m -2 Interbedded shally limestone and chalky limestone 56 Hartha -Lower part detrital limestone and shale. -Upper part interbedded marl and shally limestone and chalky 136 Sa’adi Shale and shaly limestone. 17 Tanuma Intterbedded chalky and detrital limestone. 78 Khasib Interbedded chalky limestone with shally limestone, in lower part (5m) there is one bed of shale 407 Mishrif Limeston. 14 Rumaila Interbedded shale with limestone. 25 Ahmadi Dolomite 205 Tayarat R t3 -Lower part (20m) shally limestone. -Upper part (130.5) limestone. 151.5 Shiranish -Lower part (100m) interbedded shally limestone and limestone. -Middle part (20m) chalky limestone. -Upper part (85m) consist of dolomite in the lower (55m) and the upper consist of chalky and detrital limestone. 205 Hartha -Lower part (75m) limestone in part shally limestone. -Upper part (108m) chalky limestone. 133 Sa’adi Shale in part marly limestone. 46 Tanuma -Lower part (20m) interbedded shale and limestone in top part interbedded shale and 44 Khasib ؽا رعلا بونج ىمعلأا يريشابطمل ةينوتكتلا ةيقابطلا 11 marly limestone. -Upper part (24m) interbedded limestone and chalky limestone. Limestone, in part marly limestone and only (15m) in the bottom consist of chalky limestone. 118.5 Mishrif -Lower part (35m) interbedded chalky limestone and limestone. -Upper part (78m) limestone and in the middle interbedded between limestone and marly limestone, other between limestone and limestone containers Gypsum. 113 Rumaila -Lower part (40m) interbedded shale and limestone. -Middle part (26m) marl. -Upper part (63m) in the lower (16m) chalky limestone. In the upper limestone only. 129 Ahmadi -Lower part (160) dolomite. -Middle part (24m) shaly limestone and 5m in the top is clay. -Upper part (18m) dolomite. 202 Tayarat R t4 Shally marly Limestone. 173 Shiranish -Lower part (35m) interbedded limestone and shaly limestone. -Middle part (74m) consist of marly limestone in the bottom (55m) and shally limestone in the top (19m) , in part chalky limestone. -Upper part (111m) dolomite, in part the dolomite container shale. in top part consist of chalky limestone (16m). 220 Hartha -Lower part (50m) interbedded limestone and shaly limestone and chalky limestone. -Middle part (30m) marly limestone. -Upper part (114.7m) chalky limestone. 194.7 Sa’adi Shale with one meter only limestone 56.8 Tanuma -Lower part (22m) interbedded shally and shally limestone in the bottom and shale and limestone in the top part. -Upper part (26.5m) limestone. 48.5 Khasib Limestone, in the bottom found Gupsum, in part shally and marly limestone,in the middle (thining) tow to one beds. 136 Mishrif -Lower part (61m) limestone, in part shally limestone. -Upper part (38.5m) shally limestone. 99.5 Rumaila Interbedded thick beds Marl and chalky limestone,in part thin bed of shale 138.5 Ahmadi -Lower part (27m) limestone, in part thin bed of dolomite (4m). -Upper part (103m) mostly marl , in part thinning beds of limestone. 130 Tayarat W Q -1 3 يتايبلا دمحم سيق نَشخآَ 11 -Lower part (20m) shally limestone -Upper part (91m) interbedded dolomite and limestone, in part thin beds of shally limestone and Glogonite in the top. 111.5 Shiranish -Lower part (80m) limestone. -Middle part (75m) dolomite. -Upper part (21m) limestone. 176 Hartha -Lower part (21m) limestone. -Upper part (99m) interbedded shally and chalky limestone. 120 Sa’adi -Lower part (20m) marl. -Upper part (27m) interbedded shale and limestone. 47 Tanuma Interbedded shally and shally limestone ,in part bed of shale (5m). 53.5 Khasib -Lower part (150m) interbedded chalky limestone and limestone , in part found Reudest. -Upper part (90m) limestone. 240 Mishrif Limestone. 30.2 Rumaila -Lower part (15m) shally marly limestone. -Middle part (127m) interbedded chalky limestone and limestone, in the lower found Gypsum. -Upper part (13.7m) shale with limestone. 155.7 Ahmadi -Lower part (95m) shaly dololimestone. -Upper part (36.5m) interbedded shale and dolomite. 131.5 Tayarat W Q -1 1 5 -Lower part (51m) marl. -Middle part(30m) interbedded limestone and marl. -Upper part (33.5m) marly limestone. 114.5 Shiranish -Lower part (114m) marly limestone. -Upper part (74.5m) interbedded dolomite limestone and limestone. 188.5 Hartha -Lower part (38m) limestone. -Middle part (45m) interbedded chalky and marly limestone. -Upper paet (50m) chalky limestone. 133.5 Sa’adi Shale, in part contains thin beds of shally limestone. 39 Tanuma Limestoe, in middle part contain beds of shale. 53.5 Khasib Limestone contain in the middle part Rudist. 172 Mishrif Pure limestone. 71 Rumaila -Lower part (20m) shale. -Middle part (58m) interbedded limestone and shally limestone. -Upper part (68m) shale and chalky limestone. 146 Ahmadi -Lower part (35m) limestone. -Upper part (47m) marly limestone. 82 Shiranish N o o r1 ؽا رعلا بونج ىمعلأا يريشابطمل ةينوتكتلا ةيقابطلا 11 Interbedded chalky and detrital limestone, in part(upper) Glogonite. 32 Hartha -Lower part (28m) Oolitic detrital limestone. -Upper part (103m) limestone , in part shally and marly limestone. 131 Sa’adi Inter