Geological feature of South West- North East Kurdistan

Dr. Arzu Javadova

S1 Site – Plot Plan, 2014

Shakal Garmian Kurdamir Halabja

Sarqala-1Mil Qasim-1

ЮЗ СВ

Qamar-1

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Shakal-2

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Halabja-1

NW

1’

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60, км

Simplified stratigraphy

e

1 fault-bend anticlines

fault-bend anticlines

Q

Pliocene deposits

Miocene depositsUpper Cretaceous deposit

Lower Cretaceous deposits

Middle And Lower Triassic

Paleozoic deposits

Pre Cambrian basement

Late Tertiary Structural Evolution in the Zagros Orogenic belt of SE-NW Kurdistan

Shakal

Thrust

Kalar

Thrust

Kurdamir TopkhanaChia Surkh

Qara dagh

Sarqala

Shakal

Main fold belt zones:

Low Fold Belt

• 38 total identified structures

• 28 structures with shows

• 4 failed structures

6 undrilled blocks

• Geologic Success Rate: 90%

High Fold Belt

• 27 total identified structures

• 12 structures with shows

• 5 failed structures

• 3 structures currently being

tested

• 10 undrilled blocks

• Geologic Success Rate: 70%

Thrust belt• Remains untested

Main exploration challenges:

• Much lost during decades of political instability

• Large distances between wells • Large traps buried by Pliocene

not seen on satellite imagery • Active deformation• Wellbore instability and over

pressured zones

Tertiary Oil

Cretaceous Oil

Jurassic Oil

Triassic oil

Tertiary gas

Cretaceous gas

Jurassic gas

Triassic gas

NW-

SE

Hanging wall traps Stratigraphic play

LOW FOLD BELT HIGH FOLD BELT

4 structural domains ranked by hydrocarbon prospectivity, quality and

risk

Taurus Foothills Zone- Generally heavy oil

- Probably low % recovery- Low geological risk

- Large in place resources- Limited infrastructure

Zagros Foothills Zone- Large to supergiant oil/gas condensate fields

- Low geological risk, higher gas to oil ratios- Medium to high drilling risk and cost

- Close to existing infrastructure

Zagros Mountains Zone- Gas prone; Minor oil shows- Medium-high risk and cost

- Scarce infrastructure

- Taurus Mountains Zone

- Generally heavy oil

- Large range in % oil recovery

- Scarce infrastructure

- Large in place resources

- Low to medium risk

Gas

prone zone

Heavy Oil

prone zone

Light oil

prone zone

• Multiple Source Rocks

— Paleocene, Cretaceous, and Jurassic

• Multiple Reservoirs

— Pliocene to Cretaceous targets (shallow to deep targets)

• Top Seals and traps

— Effective evaporitic seals

— Effective fine clastic seals

• Favorable timing of trap formation v. hydrocarbon migration

— Main Zagros deformation Miocene–Present

— Late hydrocarbon generation into existing, sealed traps

— Re mobilization of existing oil pools

2 major, producing plays:

- Tertiary Main Limestone Group and Upper-Mid Cretaceous

Group

- Multiple source rocks (Paleocene, Cretaceous, Jurassic,

Triassic)

- Multiple reservoirs (Miocene to Triassic). Mainly fractured

carbonates

- Excellent evaporite and shale top seals

- >100 large, undrilled anticlines

- Favorable timing of trap formation v hydrocarbon

generation-migration

- Contractional tectonics from Late Cretaceous §Main

deformation Miocene – today (Zagros and Taurus fold

and thrust belts)

- Current hydrocarbon generation and abundant

hydrocarbon seeps

AIMS AND CONTENTS

To give an updated overview of hydrocarbon exploration in Kurdistan

Location and regional tectonics

Summary of current hydrocarbon exploration

Summary of petroleum systems Tectonostratigraphic evolution taking into the account recent field data

Main challenges to exploration

Review of structural domains of the orogenic belt & structural feature of recent discoveries

SE

Pg

Lower Cretaceous

Pg

Key Message for High Fold Belt Zone:

Porosity reduction in limestone decreases exponentially with depth

Increased compaction leads to the development of stylolite's

Because the depth is greater than ~2000m dolomitization is critical for porosity & perm preservation

The basic problem in carbonate porosity concerns not the creation but rather its preservation due to

pore-filling cement in the form of calcite, anhydrite, dolomite and salt

Outcrop of limestone formation of Jeribe Near Darzila village close to Shakal area

Sustainable system of sub vertical fractures in sub- meridional and sub latitudinal trend.

Sub latitudinal fractures often disclosed (without mineral filling)

packstone,

greystone

Sedimentation

environment:

internal ramp

Fracture porosity +

5% micro porosity

mudstone,

vackstone

external ramp

13% micro porosity

Fractured reservoirs Oligocene carbonates. Close to Sarqala area

Lower Fars

Jeribe

Shiranish

Mil Qasim

Upper

Fars

Looking NELooking N

Outcrop of Lower Bakhtiari formation near Mil Qasim area.

Some joints are bed confined, others are through-going, enhancing fluid migration.

Depending on mechanical unit could be bed limited or through going

Upper Fars

Lower Fars

Shallow water carbonate ramp

facies very analogous to Tertiary

carbonate facies in Kurdistan.

The only difference is age.

Reservoir is intensively

dolomitized and fractured. High

Production Rates is related mainly

to fracturing

SW NE

Lithological

column

Lithology

description

Seal

reservoir

source

rocks

Key Tectonic Regional EventsOil and Gas

fields

sandstone

mudstone Seal

Reservoir

claystonesandstone

silstone Sealsandstone

conglomerate Reservoir

mudstone

claystone

anhydri te ha l i te

Jeribe limestone Reservoir

Dhiban anhydri te ha l i te Seal

marly l imestone

Kurdamir,

Topkhana

Gercus mudstone Seal

silstone

claystone

Shiranish mudstone

Kometian limestone

Qamchuqa

or Balambo

marly

limestone

Reservoir

source

Rock

Mil Qasim

Pulkhana,Sarqala

Kurdamir

Topkhana

Pulkhana,Has ira ,

Sarqala

Pulkhana,

Kurdamir

Topkhana Chia

Surkh

Pulkhana,

Topkhana, Shakal ,

Kurdamir

Development of

Mesopotamian basin and

sediment infill

Tectonic extension & HC

generation

Stratigraphic unit

sandstone

conglomerate

argillaceous,

marly

limestone

argillaceous

limestone

Contraction & Zagros Mountain

building & anticline growth. HC

generation & migration

Ihrahim

Azkand

Anah Tarjil

Baba &

Bajawan

Sheikh Alas

Palani

Reservoir

Basin infill by carbonate rocks

& episodic tectonic

Progressive shallowing

upwards to evaporitic

conditions

Mil QasimUpper

Bakhtiari

Lower

Bakhtiari

SealLower Fars

Upper Fars

Seal

Reservoir

Paleocene

Cretaceous

Euphrates

Serikagni

Jaddala Pila

Spi Avanah

Aaliji

Reservoir

Seal

Source

rock

Reservoir

Upper Pliocene

& recent

Lower Pliocene

Upper Miocene

Middle Lower

Miocene

Oligocene

Eocene