northern, western and southern orogenic belt information.

1. Orogenic Belts of
Pakistan
By Bassam nasir kaimkhani

2. NORTHERN BELT OF PAKISTAN

3. THE HIMALAYAS
• 50 million years ago the Neotethean Sea disappeared due
to the great collision of Indian Plate and Eurasian Plate.
• This collision give rise to the Himalayas orogenic belt.
• Himalayas are still over-lifting upward about 4-10 mm/y
and are eroding about 10 mm/y.
• The average width of Himalayas is 160-400 km and
altitude is 8000m.
• The Himalayas are extended over 3000 km from East to
West and the countries in which the Himalayas are
exposed are Pakistan, China, Nepal, Bhutan & India

5. THE INDUS
SUTURE ZONE
It represents the
Northern limit of the
Himalaya also known as
Main Mantle Thrust
(MMT).
It is about 5000 m in
altitude. It is also known
as Trans Himalaya, or
more locally Ladakh
Batholith.
Widespread volcanism in
this volcanic arc was
caused by the melting of
the mantle at the base of
the Tibetan block,
triggered by the
dehydration of the
subducting Indian
oceanic crust.
It is the thrust between
Lhasa Block and the
Higher Himalayas.

6. • THE HIGHER HIMALAYAS:
• The higher Himalayas are about (8000-8800 m) above sea level.
• They are about 100 km wide and are spread over the Indian Plate.
• They are thrusting downward onto the lesser Himalayas.
• The boundary thrust between Higher & Lesser Himalayas is Main Central
Thrust (MCT).
• LESSER HIMALAYAS
• After Main Central Thrust, the Lesser Himalayas continue.
• The lower or lesser Himalayas are about (1500-3000 m) in altitude and are
about (65-80 km) in width.
• They are thrusting onto Sub Himalayas.
Conti……………………….

7. Conti……
• The Sub Himalayas:
• The Sub Himalayas start after the Main Boundary Thrust (MBT), which is
present below the Lesser Himalayas.
• The Sub Himalayas are about (600-900 m) in altitude and are about (1-25 km)
in width. Then the Main Frontal Thrust (MFT) occurs.
• Foreland Basin, Fore Bulge & Indian Shield:
• After the Main Frontal Thrust (MFT) a Foreland Basin is formed, where all the
eroded sediments of Himalayas are deposited.
• After the Foreland Basin, a Fore Bulge is present which is of about 500 m in
altitude.
• Moreover moving towards South the Indian Shield rocks are found, which are
also called ‘basement rocks’ or ‘cretonic rocks’.

8. WESTERN BELT OF PAKISTAN

9. SULEIMAN-KIRTHAR RANGE
• After the collision between the Afghan block and Indian plate,
the Sulaiman Range uplifted which is 10 km thick.
• Indian western continental margin sediments are deposited
on Sulaiman Range.
• Sulaiman-Kirthar range extends up to 1250 km from
Waziristan to Karachi.
• The Sulaiman Range extends from Waziristan to Quetta with
the altitude of approximately (3200 m).
• Sulaiman Kirthar range is about (60-150 km) wide.
• The Kirthar Range extends about (750 km) from Quetta to
Cape Monze, and its altitude is about (2300 m).

11. SOUTHERN BELT OF PAKISTAN

12. MAKRAN
SUBUCTION ZONE
• The first subduction started in Early Cretaceous.
• In this era the African plate started subducting
under the Afghan block and Red Sea disappeared
(30 Ma).
• The second subduction started in Middle Cretaceous
when Arabian plate subducted under Afghan block,
which formed Dalbandine trough (inter-arc basin)
which is between Ras Koh and Chagi magmatic
arcs.
• In further thrusting Afghan block and Chagi
thrusted on Ras Koh in Paleocene and Koh-e-Sultan
formed in the north of Chagi.

13. MAKRAN
SUBDUCTION ZONE
• Ras Koh and Chagi magmatic arcs extend into
Iran (Bazman) which is about (500 km) and
their width is (150 km).
• The Ophiolites are found on Ras Koh of about
(110 Ma) which indicate the closing of oceans.
• Due to the collision, Ras Koh and Chagi
uplifted about (3000m).
• Arabian plate is moving at the speed of 4
mm/y towards south and the Makran
accretionary prism is moving towards south at
1 mm/y.