ppt related Siwalik- Stratigraphy, sedimentation, distribution, flora and fauna of Siwalik

1. Presented By
PRAMODA G
Faculty in Geology
Yuvaraja College
Presentation on
“Siwalik- Stratigraphy, sedimentation,
distribution, flora and fauna of Siwalik”

2. • Introduction
• Stratigraphy
• Sedimentation
• Distribution
• Flora and Fauna
• Conclusion
• References
CONTENTS

3. INTRODUCTION
1. The name Siwalik was initially given by Captain
P.T.Cautley in the early 19th (1832) to the outermost
Sub-Himalayan Ranges.
2. He discovered the Siwalik fossils while digging for
the Ganga canal near a Shiva temple at Haridwar
(now in Uttaranchal) in the Ganga Valley.
3. Hence the name Siwalik was given to the sedimentary
rocks entombing the fossils.
4. Subsequently, it was applied to the mammal-bearing
horizon of the Himalayan foothills Neogene
continental deposits.

4. 1. Tertiary formations stretching from the Indus
River in the west to Irrawady River in Myanmar
in the east.
2. he Siwalik Group occurs in Potwar basin in NW
Pakistan and extends along the Himalayan
foothills to Arunachal Pradesh foothills in the SE,
except for a small break near Sikkim. The group is
about 7 km thick and ranges from Middle
Miocene to Early (?) Pleistocene (16.8 to 0.22
Ma) in age.
3. Most of the Siwalik hills are less than 1000m rom
MSL and running parallel to Himalaya.
4. Siwalik separated from Indo-Gangetic plain by
Main Boundary Fault (MBF)

6. • High degree of lateral and vertical facies variation
and poor continuity of lithological characteristics.
• Siwaliks divided into three Lower, Middle and
Upper units based on their correlation fauna with
similar fauna of Europe.
• Siwalik sediments classified into 4 environments
A. Piedmont
B. Outwash plains
C. Channel and flood plains
D. Lacustrine
• Thickness of the molassic sediments between
5000 m to 60003

7. Chronostratigraphic divisions of Siwalik

8. Lithostratigraphic divisions of Siwalik

11. Fauna and Flora
• The Siwalik Group is well known for its wealth of
vertebrate fauna, though they are confined to only
certain horizons and only some of them are of
biostratigraphic importance.
• Occurrence of hominoids in almost all the
formations.

13. • The distribution of Siwalik from Brahmaputra
valley to the Potwar Plateau of Pakistan and cover
the Indian states of Jammu and Kashmir, Punjab,
Himachal Pradesh, Haryana, Uttarakhand, Uttar
Pradesh and Assam. The distribution of Siwaliks
inNorth-western region of India

14. Jammu and Kashmir
• The Siwalik sediments overlie the Murree in this
sector of Kashmir Himalaya.
• Complete development of Siwalik can be seen
in the Jammu Hills, where they attain a
thickness of about 6000 m with an outcrop
width of about 40 km as seen along the Chenab
section in Riasi-Aknoor sector and in Ramnagar-
Samba sector.

15. Himachal Pradesh
• The Siwalik Group in Himachal Himalaya forms a
parallel foothill belt along the southern margin of the
Paleogene Sirmur belt between the Ravi and the
Yamuna rivers.
• The Siwalik sediments generally overlie the
Dharamsala Group.
• A gradual transition from Kasauli to Lower Siwalik
(Nahan) is seen.
• However, at Dharamsala. Sarkaghat and Nalagarh
the Siwalik Group directly overlies the Sirmur Group.
• the Lower Siwalik rests on Dagshai with a profound
unconformity, indicating a period of earth
movements.

16. Uttaranchal
• Siwalik Group here extends for over 250 km and is
25 km wide, but much less than those in Himachal
Pradesh.Total thickness is about 4500m
• Kalagarh one of the principal areas hominid and
other vertebrate fossils and dominantly
arenaceous.
• Clays, however, appear in Ramganga-Palain river
sections. Middle Siwalik is best exposed south of
Dehra Dun in the Mohand section in the core of
Mohand anticline, where it attains a thickness of
about 1800 m. It is predominantly made up of
multi-storied sandstone.

17. West Bengal
• Terai region of the northern part of jalpaiguri and
Darjeeling districts ofWB.
• Sandstone is usually soft and friable but close to the
thrust highly indurated and sheared.
• In the upper pebbly horizon pebbles made up of
quartzite, jasper and rarely of phyllite are present
• . Besides these lenses of lignite and fossil wood
commonly occur in the Siwalik.

18. Arunachal Pradesh
• The Siwalik Group occurs as a linear belt all along
the foothills from the border with Bhutan in the
west, to Roing in the Dihang Valley in the cast u
here it ends against the Roing fault.
• Its northern limit is defined by the Main Boundary
Fault separating it from the pre-Tertiary sequence.
while in south the Brahmaputra alluvium defines its
boundary. which at places appears to he tectonic
(Foothill fault).T
• he sediments have been divided into Kimi, Dana.
Subansiri and Kimin Formations.