Sedimentology of sin jar and khurmala formations (Paleocene-Lower Eocene)‎ in northern Iraq

Other Title(s)

رسوبية تكويني سنجار و خورمانة (بانيوسين-ايوسين الأسفل)‎ في شمال العراق

Dissertant

Salih, Amani Luayy Muhammad

Thesis advisor

Tamir Agha, Mazin Yusuf

Comitee Members

al-Shammari, Thamir A.
al-Jumayli, Sad Salih
al-Rawi, Dhya Y.
al-Shikli, Sad S.
Hazza, Sawsan H. F.

University

University of Baghdad

Faculty

College of Science

Department

Geology Department

University Country

Iraq

Degree

Ph.D.

Degree Date

2013

English Abstract

njar and Khurmala Formations represent the middle part of the Tectonostratigraphic AP 10 Megasequence, which were deposited during the Middle Paleocene – Lower Eocene.

This study involves reconsidering the sedimentology, stratigraphy and regional paleogeography of these units in the exposure area of the High Folded Zone.

In order to achieve this, the sites of previous works are visited and more samples collected, as well as describing and sampling new localities.

Twelve outcrops sections and seven subsurface boreholes are studied in present study.

The outcrop sections (Darbandikahn-Dar, Sulaimani Gerda-Sul, Kalksmaq-Kal, Daigala-Dai, Hijran-Hij, Harir-Har, Bekhema-Bek, Junara-Jun, Aqra-Aqr, Bary Bahar -Bar, Babylo-Bab, and Wara Milli-War) are located within the High Folded Zone from the Sulaimaniya city to Dohuk city; while the uubsurface sections (boreholes) (Bashiqa-Bas, Kirkuk 117, Jabal Kand-1, Atshan-1, Butmah-2, Mushora-1, Mityaha-1) are located within the Low Folded Zone.

Petrographyic study and microfacies analysis of Sinjar and Khurmala Formations enabled the recognition of sixteen microfacies interpreted and grouped into six facies associations: The outer shelf association consists of thinly bedded brown and yellow to grey in color limestone.

This association is subdivided into three microfacies as follow: Calcisphere Wackstone (A1), Small benthic Foraminifera wackstone (A2), Fossiliferous mudstone (A3).

Fore-reef association mostly consists of medium to thick beds of limestone that are buff to grey in color.

This association is subdivided into two microfacies as follows: Discocyclina-Numulite packstone (B1) and Large foraminifera- red algae grainstone (B2).

Reef association (C) consists of medium to thick bedded limestones that are light brown to dark grey in color.

There are four microfacies observed in this association: Coralligenous floatstone-framstone (C1), Coralligenous-algal boundstone (C2), Bryozoan bioclastic floatstone-framestone (C3) and Intraclast-fragmented bioclast backstone-grainston (C4).

Back reef association (D) is characterized by massive and thick beds of limestone, with pale brown to yellow color.

There are three microfacies within this association: Bioclastic Packstone-Grainstone (D1), Red algae benthic Wackstone-Floatstone (D2), and Large-Benthic Bioclastic Floatstone (D3).

Lagoon association (E) is characterized by thin to medium limestone beds with a color light gray to yellow.

There are three microfacies in this association: Peloidal-miliolid packstone-grainstone (E1), Red algae - miliolid packstone (E2), and Wackstone - packstone (E3).

And interatidal association (F).

The Sinjar and Khurmala formations are affected by five diagenitic processes; these are: micritization, cementation, dissolution, dolomitization and compaction.

The less effective process is micritization, cementation and compaction, while the most II effective are dolomitization and dissolution which have direct effect upon carbonate pores systems.

The studied succession was deposited during three sedimentological stages; The first stage shows the domination of marginal marine depositional environment (Kolosh) to the westward while to the east-southeast, it is covered by isolated carbonate shelf bounded by reef association facies which separates the shallow part of the shelf (Lagoon and back-reef facies associations) and the deeper part (fore-reef).

Where observed the lagoonal facies in the Bekhma, Daigala and Kalkas Mag sections.

The reef facies is observed in Sulmani Gerda section and the fore-reef facies is shown in Darbandkhan section.

Therefore the position of the backreef facies are suggested according to these facies.

During the second stage the basin is developed by growth of isolated carbonate shelf from southeast to northwest during transgression period, which covered the north part of the Kolosh basin, where appeared this facies in Hijan, Harir sections, and covering the southwest part of Aliji basin, where this formation appears in Atshan-1 and Butmah-2 sections.

Therefore we can see lagoonal facies in the sections Taq taq-1, Kirkuk-117, Junara, Bekhmah, Bashiqa, Babylo and Bery Bahar; the back-reef facies is located in Daigala, Aqra., and Mushora-1.

While the reef facies is observed in the Wara Milli, Kalkasmaq, Sulaimani Gerda, and Darbandikhan sections.

The final stage represents the still stand period where the sea level is stilled and the prograding growth becomes the major sedimentological parameter which effect the carbonate shelf.

Therefor during this stage the reef facies is shifted faraway seaward and replaced by the back-ree

Main Subjects

Earth Sciences, Water and Environment

No. of Pages

187

Table of Contents

• APA
• MLA
• AMA

Language

English

Data Type

Arab Theses

Record ID

BIM-609392