This document provides an overview of the Central Indus Basin, a gas-prone geological province in Pakistan. It is divided into three units: the Punjab platform in the east, the longitudinally subsiding Sulaiman depression in the center, and the folded Sulaiman fold belt in the west near the collision zone. The region contains source rocks from the Cretaceous, Jurassic and Eocene periods. Important reservoir rocks include limestones from the Eocene, Paleocene and Cretaceous, with a total thickness of 1,500m. Seal rocks include marine and shallow marine mudstones. Traps formed from stratigraphic changes and faulting. Tectonics involved basement uplift and compression

1. Central Indus Basin
• INTRODUCTION
• SOURCE ROCKS
• RESERVOIR ROCKS
• SEAL ROCKS
• TRAPPING MECHANISM
• TECTONIC FRAMEWORK
• DRILLING HISTORY

2. Introduction
 Upper segment of Lower Indus Basin
 A gas prone province
 Includes Pakistan famous Sui gas field
 Three units.
1. punjab platform
2. sulaiman depression
3. sulaiman fold belt

3. Punjab platform
 Eastern segment of Central Indus Basin
 Dips westward in to Sulaiman depression
 Sargodha Ridge marks the north-eastern boundary
 Sukkr Ridge marks the southern boundry
 No surface outcrops of sedimentary rocks
 Seismic study have revealed the presence of pre-cambrian to
cambrian rocks in subsurface

4. Sulaiman depression
 Longitudinally oriented area of subsidence
 Formed as a result of collision between two plates
 Merges into punjab platform in the east

5. Sulaiman fold belt
 Western segment of Central Indus Basin
 Located near collision zone
 Contain large number of disturbed anticline features
 Contain oldest rocks of Lower Indus Basin i.e wulgai formation
of Triassic age

6. Source rocks
 Cretaceous: Sembar, Goru and Mughalkot formation
 Jurassic: Datta and Shinawari formation
 Eocene: kirthar formation contain Oil-Shale of TOC 11℅
Habib Rahi limestone have TOC 5.25℅

7. Reservoir Rocks
 Eocene: Sui main/Sui upper/Habib Rahi limestone
 Paleocene: Ranikot limestone/sandstone
 Cretaceous: Pab/lower goru sandstone
Cumulative thickness of reservoirs: 1,500m

8. Seal Rocks
 Marine mudstone of kussak formation
 Shallow Marine mudstone of Dandot formation
 Shales of Chhidru/Datta/Ranikot formation
 Ghazij shale are the regional seal in punjab platform

9. Trapping mechanism
Potential stratigraphic traps are
 Beneath base tertiary or base miocene unconformities
 fault-related structures
 Fluvial shales of Murree formation at some places

10. Tectonic framework
 Geologic Structures in Central Indus Basin were formed as a result of
Basement uplift and Compressional tectonics
 Basement uplift: Gentle Domal structures like khairpur, kandhkot and
Mari etc.
 Compression: Inner and outer Sulaiman folded zone
 These structures ranges from simple dome(sui) to complex Duplex
types(outer folded zone)

11. Punjab platform
 Tectonically stable area
 Regional scale monocline dipping gently towards
Sulaiman depression
 Tilted eastward in Paleozoic time due to non-orogenic movements
 Tilted westward since Mesozoic due to collision of Indian and Eurasian plate

12. Sulaiman depression

13. Sulaiman fold belt
 Represents compressional and strike-slip tectonics
 Represents thin-skinned tectonics where rigid Basement
is not playing any major role
 The sedimentary cover is Imbricated due to severe
compression and its intensity increases from northwards of sui

14. Drilling history