Keywords : Biostratigraphy


Planktonic Foraminiferal Biostratigraphy of Shiranish Formation in Sara Anticline in Dokan Area, Northeastern Iraq

Yassen Hassan; S. AL-Hadidi S. AL-Hadidi

Iraqi National Journal of Earth Science, 2022, Volume 22, Issue 1, Pages 1-14
DOI: 10.33899/earth.2022.174662

Planktonic foraminiferal biostratigraphy of Shiranish Formation was studied in Sarah's anticline at the Dokan area, Sulaymania governate in, northeastern Iraq. The studied section consists of marl and marly limestone, Sixty-three Planktonic foraminiferal species belonging to seventeen genera have been recognized which permits the recognition of six zones; these are from older at the base
6- Abathomphalus mayaroensis interval zone (Part).
5- Gansserina gansseri interval zone.
4- Globotruncana aegyptiaca interval zone.
3-Globotruncanella havanensis interval zone.
2- Globotruncanita calcarata total range zone.
1-Globotruncana ventricosa interval zone (Part).
The Planktonic foraminiferal zones were correlated with other zonal schemes in and outside Iraq. They are considered to be extending from Middle Campanian to Late Early Maastrichtian.

Planktic Foraminiferal Biostratigraphy of the Upper Part of the Damlouk Member, Ratga Formation, Western Desert, Iraq

Imad Ghafor; Basim Al-Qayim

Iraqi National Journal of Earth Science, 2021, Volume 21, Issue 2, Pages 49-62
DOI: 10.33899/earth.2021.170385

The basinal part of the Damlouk Member upper sedimentary cycle of the Ratga Formation exposed in the Qaim area of the Iraqi western desert is examined. The studied section consists of marlstone, marly and phosphatic limestone, and planktic foraminifera-rich limestone beds. Detailed study of the planktic foraminiferal assemblages of these rocks revealed the occurrences of (30) species belonging to (11) genera. The stratigraphic distribution of these species permits the recognition of three biozones. These are from the lower to upper part of the section: - Acarinina bullbrooki Zone, (Middle Lutetian), Morozovelloides lehneri Zone, (Late Lutetian), Globigerinatheca semiinvolutaHantkenina alabamensis Zone, (Early Bartonian). These zones indicate that the studied section of the Ratga Formation (Damlouk Member) is of Middle-Late Lutetian to Early Bartonian age. These biozones are correlated with different local and regional studies.

Geological history, Ichnofacies and Sequence Stratigraphy of the Eocene – Oligocene Boundary at Sinjar Area, Northwestern Iraq

Majid Al-Mutwali; Hiba Al-Rubai

Iraqi National Journal of Earth Science, 2021, Volume 21, Issue 1, Pages 27-45
DOI: 10.33899/earth.2021.170380

Three outcrop sections for the Eocene- Oligocene boundary have been studied in Sinjar anticline northwestern Iraq. This study includes the lithostratigraphy, biostratigraphy and the identification of trace fossils and related ichnofacies in order to report the geological history of this boundary in the frame of sequence stratigraphy. Jaddala Formation, which is composed of marl and marly limestone, represents deep (outer shelf-upper bathyal) Eocene facies, Palani and Tarjil formations represent deposition in deep basinal environments during Early and Late Oligocene sequences.
    The Eocene- Oligocene boundary in Sinjar area represents a disconformity surface, where the deposition ceased in the Middle Eocene (Lutetian) at the end of Jaddala Formation, forming  the firmground  Glossifungites Ichnofacies which embrace  Thalassinoides ichnotaxa in Jaddala section, and the hardground  Trypanites Ichnofacies  in Sharafiddin section, while at Sinjar section, a chalky limestone bed deposited at the Early Oligocene (Rupelian) Palani Formation representing Skolithos Ichnofacies.
    A rapid wide transgression took place at the end of Early Oligocene (Rupelian) leading to the deposition of Palani Formation, and continued through the Late Oligocene (Chattian) leading to the deposition of Tarjil Formation.

Planktonic Foraminifera Biostratigraphy of Shiranish Formation in Piramagroon Anticline, NE Iraq

Ahmed Al-mutiwty; Abdullah Shihab

Iraqi National Journal of Earth Science, 2020, Volume 20, Issue 2, Pages 43-63
DOI: 10.33899/earth.2020.170369

67 planktonic foraminiferal species were identified from the Shiranish Formation. On the basis of the stratigraphic distribution of the planktonic foraminiferal assemblages recognited of six biozones within the Shiranish Formation representing an age ranging from Middle Campanian – Early Maastrichtian, these zones are from older at base:
6 -Planoglobulina acervulinoides Interval Zone.
5 - Contusotruncana contusa Total Range Zone.
4 -Gansserina gansseri Interval Zone.
3 - Globotruncana aegyptiaca Interval Biozone.
2 -Globotruncanella havanensis Interval Biozone.
1 -Globotruncana ventricosa Interval Biozone

Planktonic Foraminiferal Biosatratigraphy of the Eocene – Oligocene Boundary at Sinjar Area, NW Iraq

Hiba Al-Rubai; Majid Al-Mutwali

Iraqi National Journal of Earth Science, 2020, Volume 20, Issue 2, Pages 1-18
DOI: 10.33899/earth.2020.170355

The present study deals with the lithostratigraphy, biostratigraphy and chronostratigraphy of the Eocene- Oligocene boundary in three surface sections in Sinjar anticline, northwestern Iraq. Jaddala Formation composed of marl, marly limestone represents deep Eocene facies, Palani, and Tarjil formations represent Early and Late Oligocene sequences. Sixty-two planktonic foraminiferal species belonging to sixteen genera have been recognized which permit the recognition of four Zones; these are from older at the base:  
  Globorotalia opima opima Total- Range Zone (P21)
  Globigerina ampliapertura partial- Range Zone (P20)
  Pseudohastigerina micra Interval Zone (P 19)
Globigerinatheka subconglobata subconglobata Partial Range Zone (P11) (Part).
      
The Eocene- Oligocene boundary in Sinjar area represents disconformity surface, where the deposition ceased in the Middle Eocene (Lutetian) at the end of Jaddala Formation, then deposition started at the Upper Early Oligocene due to rapid wide transgression, leading to the  deposition of Palani (Rupelian) and Tarjil (Chatian) formations, which consist of thinly laminated hard white-pale brown intercalation of marly limestone and marl beds.

Calcareous Nannofossils Biostratigraphy of Shiranish Formation (K-306) well, Northern Iraq

Maryam Al-Maamari; Omar Al-Badrani

Iraqi National Journal of Earth Science, 2019, Volume 19, Issue 2, Pages 1-10
DOI: 10.33899/earth.2019.170278

Twenty Samples of Shiranish Formation from the well (K-306), Kirkuk area, northern Iraq, are collected and studied on the basis of stratigraphic ranges of the recorded calcareous nannofossils. Eighty-nine species in the studied section reveals five biozones arranged from oldest to youngest as follows:
1.Quadrum trifidum Interval Biozone (CC22) Part
2.Tranolithus phacelosus Interval Biozone (CC23)
3.Rienhardtites lives Interval Biozone (CC24)
4. Arkhangelskilla cymbiformis Interval Biozone (CC25)
5. Nephrolithus frequens Rang Biozone (CC26) Part
These Biozones are correlated with other calcareous nannofossils biozones, from both local and regional sections, leading to conclude the age of Campanian- Maastrichtian.

Planktonic Foraminiferal Biostratigraphy of Tanjero Formation (Late Maastrichtian) in Bekhme Area, Northeastern Iraq

Majid Al-Mutwali; Muthana Ibrahim

Iraqi National Journal of Earth Science, 2019, Volume 19, Issue 1, Pages 1-21
DOI: 10.33899/earth.2019.170035

The biostratigraphy of Tanjero Formation has been investigated within a well-
exposed section at the northern limb of Perat anticline, Bekhme area, Northeastern Iraq.
The studied section consists mainly of marl, marly limestone, and sandstone. The
formation conformably overlies Shiranish Formation (Late Campanian-Maastrichtian)
and it is overlain unconformably by the Kolosh Formation (Paleocene). The samples of
the section under investigation yielded rich and well diversified planktonic foraminiferal
taxa, where 69 planktonic species belonging to 21 genera have been recognized. The
detailed foraminiferal investigation permits the recognition of four well defined zones.
These are from older at the base:
4. Plummerita hantkeninoides Total Range Zone.
3. Pseudoguembelina palpebra Partial Range Zone.
2. Pseudoguembelina hariaensis Interval Zone.
1. Racemiguembelina fructicosa Interval Zone.
The Planktonic zones were correlated with other zonal schemes in- and outside
Iraq. They are considered to be of Late Maastrichtian age.

Calcareous Nannofossils Biostratigraphy of Aaliji Formation in Well (K- 116), Northern Iraq

Raghda Saad Al-Hyaly; Omar Ahmed Al-Badrani

Iraqi National Journal of Earth Science, 2019, Volume 19, Issue 1, Pages 35-45
DOI: 10.33899/earth.2019.170265

Thirteen samples of Aaliji Formation from the well (K-116), Kirkuk area, Northern Iraq, are studied on the basis of the stratigraphic ranges of the recorded calcareous nannofossils for sixty species, the studied section reveals five biozones arranged from oldest to youngest as follows:

Fasciculithus tympaniformis Interval Biozone (CP4)
Heliolithus kleinpellii Interval Biozone (CP5)
Discoaster mohleri Interval Biozone (CP6)
Discoaster nobilis Interval Biozone (CP7)

5. Discoaster multiraditus Interval Biozone (CP8)
These biozones are correlated with other calcareous nannofossils biozones from both local and regional sections leading to conclude the age of Middle Paleocene to Early Eocene.

Planktonic Foraminiferal Biostratigraphy of the Upper part of Balambo Formation (Lower-Upper Cretaceous) in Azmer Anticline, Northeastern Iraq

Inas Al-Khafaf; Majid Al- Mutwali

Iraqi National Journal of Earth Science, 2018, Volume 18, Issue 2, Pages 35-60
DOI: 10.33899/earth.2018.159257

The present work is a part of detailed study of biostratigraphy of Balambo Formation (Lower - Upper Cretaceous) from Azmer anticline - northeastern Iraq. Lithologically, the upper part of the studied section (Balambo Formation) consists of dark gray, reddish brown shale and marl intercalation with amonitic and marly limestone. Based on planktonic foraminifera, the studied section is divided into five main biozones and two subzones. It is correlated with collection of global regional and local previous biozones. These biozones led to conclude that the age of the upper part of Balambo Formation extends over the Latest Aptian to Middle-Late Cenomanian. Moreover, the identified biozones are from older (at bottom) to younger (at top):
5- Rotalipora cushmani Taxon range Zone.
4- Thalmanninella globotruncanoides Interval Zone.
3- Biticinella breggiensis Interval Zon.
Ticinella praeticinensis Interval Subzone.
Pseudothalmanninella subticinensis Interval Subzone.
2- Ticinella primula Interval Zone.
1- Paraticinella eubejaouensis Taxon range Zone.یتضمن البحث الحالی د ا رسة طباقیة حیاتیة لمفو ا رمنیف ا ر الطافیة لتکوین بالامبو
)الکریتاسی الأسفل الأعمى( فی طیة أزمر شمال شرقی الع ا رق. یتألف ىذا الجزء من تتابعات لطبقات - -
الطفل الرصاصی الغامق المون والطفل البنی المحمر وطبقات من المارل متداخمة مع طبقات الحجر الجیری
الامونایتی وطبقات الحجر الجیری المارلی. تم تقسیم ىذا المقطع الطباقی الى خمسة أنطقة حیاتیة رئیسة
واثنین من الأنطقة الحیاتیة الثانویة. وتمت مضاىاة ىذه الأنطقة مع مجموعة من الأنطقة الطباقیة الحیاتیة
العالمیة والإقمیمیة والمحمیة، وبیذا إتضح أن عمر ىذا الجزء من التکوین یمتد من أواخر الأبتیان المتأخر
الى السینومینیان الأوسط المتأخر. وىذه الأنطقة من الأقدم )فی الأسفل( الى الأحدث )فی الأعمى(: -
5- Rotalipora cushmani Taxon range Zone.
4- Thalmanninella globotruncanoides Interval Zone.
3- Biticinella breggiensis Interval Zone.
. Ticinella praeticinensis Interval Subzone.
Pseudothalmanninella subticinensis Interval Subzone.
2- Ticinella primula Interval Zone.
1-Paraticinella eubejaouensis Taxon range Zone.