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Geology Camp Report
CE 373 Department of Civil Engineering
IIT Kanpur
Umed Paliwal 10774
Group 5
Acknowledgment
I take this opportunity to express my profound gratitude and deep regards to Prof. Javed N.
Malik and Prof. D. Paul for their exemplary guidance, monitoring and constant
encouragement throughout the course of this camp. The blessing, help and guidance given by
him time to time shall carry me a long way in the journey of life on which I am about to
embark.
I also take this opportunity to express a deep sense of gratitude to our TA’s. Their cordial
support, valuable information and guidance, which helped me in completing this task through
various stages.
I am obliged to staff members Shitla Prasad Tripathi, Maurya sir for the valuable information
provided by them in their respective fields. I am grateful for their cooperation during the
period of my assignment.
Umed Paliwal
Group 5 Members: - 1) N.V.S. Bharat Kumbhat
2)Saurav Shekhar 3)Raj Shekhar
4)Rahul Meena 5)Sandeep Verma
6)Uday Kumar 7)Nivesh Goel
8)Vishal Katariya 9)Umed Paliwal
Introduction This report is based on the understanding and insight we gained in the field observation at Nainital in the Geological part of the CE373 course. The camp was held from 4th December 2012 to 8th December 2012conducted by Department of Civil Engineering IIT Kanpur. It was held under the guidance of Dr. Javed N. Mallik and Dr. D. Paul. During the course of these four days we visited various sites guided by our instructor. All these sites had an aesthetic appeal to the senses and also they carried a large amount of valuable geological information on the inside.
Geology of Nainital Nainital is situated in Uttarakhand which comprises of Kumaon Himalayas which are part of Lesser Himalayas whose avg. Height above MSL is about 800-2500m. Nainital is famous for lakes and the name Nainital has come from ‘Naini’ which means 9 and ‘tal’ means lake, this means that it comprises of nine lakes. Very high tectonic movement is found in this region that is the reason why stresses are not accumulated and no major Earthquake was found. Nainital region consists of three main rock formations. They are
Krol formation
Tal formation
Blaini formation
Krol formation:Further divided into 2 parts 1) Upper Krol 2) Lower Krol These are older rocks which belong to Pre-Cambrian age. Stromatolites of algae are found as they came from marine deposition. These are basically sedimentary in nature. Tal formation:These are relatively younger compared to Krol and belong to Cambrian age comprising primarily of silty shales and dolomite. These are low grade metamorphic rocks and don’t have Stromatolites. Krol formation: This is further subdivided into two types: (a) Upper Krol (b) Lower Krol Upper Krol: It consists of a thick succession light to dark grey dolomite beds separated
by thick carbonaceous silty shales. Lower Krol: They are characterized by grey fine silty slates. Blaini formation: These rocks are of glacial origin and are mixed with old sedimentary rocks. There are also numbers of faults in this region like 1) Main Central Thrust (MCT) 2) Main Boundary Thrust (MBT) 3) Himalayan Frontal Thrust (HFT) Himalaya – (Him+Alya) means“abodes of snow” – is one of theyoungest and highest mountainranges on the globe with manypeaks as high as 7000 meters and above. It isabout 2400 km in length from AfgahnistanPakistan in the west and Namcha Barwa in the east. It varies in width between 250 to 300km along its length. On the basis of elevation difference, the Himalayas can be broadly classified as:
1) Lower Himalayas (less than 1000m) The Subhimalaya forms the foothills of the Himalayan Range and is essentially composed of sediments derived from the erosion of the Himalaya. These molasse deposits, known as the Muree and Shiwaliks Formations, are internally folded and imbricated. The Subhimalaya is thrust along the Main Frontal Thrust over the Quaternary alluvium deposited by the rivers coming from the Himalaya which demonstrates that the Himalaya is still a very active orogen.
2) Lesser Himalayas (1200-3000m) The Lesser Himalaya (LH) is mainly formed by Upperdetrital sediments from the passive Indian margin intercalated with some granites and acid volcanicare thrust over the Subhimalaya along the Main Boundary Thrust (MBT). The Lesser Himalaya often appears inwithin the High Himalaya Crystalline Sequence
3) Higher Himalayas (3000-7000m) The Central Himalayan Domain, (CHD) or High Himalaya, forms the backbone of the Himalayan orogen and encompasses the areas with the highest topographic relief.
Another division of the Himalayas exists, called the Tethys Himalayas. The junction of the Lesser Himalayas and the Himadri is called MCT The junction of the Shivaliks and the Lesser Himalayas is called MBT. The junction of the Indo-Gangetic plain and the Shivaliks is called HFT.
Google Earth Plot
Summary of Field Visits
Kumaon University Lecture By Prof. Charu Pant After reaching at Kumaon University we were given a brief lecture by Prof. Pant about the geology of Nainitaal the proceedings of the same are as follows: - Britisher’s founded Nainital in around 1840. It is a hilly area with a thick forest cover and Naini lake lying in the Centre. The lower part is known as tallital and the upper part mallital. General elevation is around 2000m above MSL. Nainital peak has an elevation of 2096m. Nainital developed as a hill station soon after and became a major attraction for tourists. As the population increased with it increased the pollution. Naini Lake is polluted because of the sewage water being dumped in it. Due to the organic waste coming in the oxygen content has been lowered. The bacteria present in water requires oxygen for decomposing the organic waste, the lowered oxygen content has led to death of fishes. A lot of remedial actions were taken up: - 1) Artificial aeration 2) Introduction of Gambusia Fish (it was stopped as the fish was eating the lava of some desired fishes) To solve the problem of landslides britishers made 63 ducts for avoiding seepage as rocks are slaty and it can cause landslide by increase in pore water pressure and after britishers those ducts were also facilitated with sediment traps to avoid sedimentation in lake from hill flow.
Museum We were exhibited various kinds of rocks and rocks structures like Low grade metamorphic rocks (slate, mylonite) Igneous rock structures (basalt, scoria) Sedimentary rock structures (stalagmite, rain prints, tracks and trails) Metamorphic rock structures (banded gneiss, wave ripples) Tectonic structures (mylonite, conjugate folding)
In addition to the above, various minerals, fossils and stones were also shown
Metallic minerals (pyrite, galena) Rock forming minerals (biotite, garnet) Radioactive minerals (uranite, monazite) Gemstones (quartz, amethyst) Plant fossils and invertebrate fossils
Ranibagh Bridge GPS Coordinates: Latitude = 29°17’33.8” Longitude = 79°32’51.8” We were taken to an area beside a water stream and were asked to select any 5 different types of rocks and identify them. Also we have to draw the top view and cross-section view of the stream flow labeling various river forms in that. The water over there is coming from Thermal Spring and has an approximate starting temperature of 7.5°C. Lower Shivaliks are generally very fine-grained muddy deposits deposited by ancient rivers. Various types of sedimentary structures can be observed over here. These are basically riverine mudstone. Middle Shivaliksare riverine deposits of sandstones with high energy of flow. These are alsoDepositsfrom ancient rivers and various sedimentary structures can be observed here. These are generally coarse grained. These are formed by high flows
Minerals: Quartz, Mica, Olivine Shape: Sub-angular Source: Greater Himalayas Kind: Igneous rock Name: Granite
Minerals: Clay, Mica Shape: Slate type Source: Greater Himalayas Kind: Metamorphic rock Name: Slate
Minerals: Clay Shape: Foliated Source: Lesser Himalayas Kind: Sedimentary rock Name: Shale
Minerals: Feldspar, Mica, Sand Shape: Sub-Angular Source: Shiwaliks Kind: Sedimentary Name: Sandstone
Minerals: Silica Shape: Angular Source: Lesser Himalayas Kind: Metamorphic rock Name: Quartzite
Boundary Between lower and Middle shivaliks
Cross sectional view of river flow:
Geomorphic Sketch of River:
Channel bar
Point bar Lateral bar
Channel bars are those, which divide the stream.
Longitudinal bars are those, which are along the stream flow.
River Characteristics:
Cut back
Point bar
Valley Length
Bed load
Suspended load
Longitudinal/Channel bar
River Bed
The flow type of the river is Helical Flow.
All sizes of stones are available from pebbles to boulders.
Both Sedimentary and Metamorphic rocks are transported by the river flow.
Basalt Shale converting to slate
AMRITPURI GPS Coordinates:
Latitude = 29°17’47.5”
Longitude = 79°33’47.1”
Here we were asked to find shear zone (MBT). This is the area where large number of
Igneous rocks from Lesser Himalayas and Shiwaliks are found. Both Igneous and
Sedimentary rocks are found in this area.
We observed Granite and Basalt. Degassing of rocks and plutonic intrusions in some
rocks indicate the presence of Igneous rocks.
Many shear planes and joints were observed in the
Shear zone with majority of sand stone. Sand stone
is present in MBT in high shear zone.
The volcanic rocks are much older that Shiwalik rocks. Large green schist is formed due
to low-grade metamorphosis. Sand stones are in direct contact with mafic igneous
rocks, metamorphosed to quartzite due to high pressure.
MBT
Shiwaliks
(Sandstone)
zone1
Fault zone
zone 1 & 2
Lesser Himalayas
(Igneous rocks)
zone 2
Degassing
Basalt
KILBARI ROAD
GPS Coordinates: Position 1
Latitude = 29°24’29.3”
Longitude = 79°26’47.9”
Elevation= 2269m
Carbonaceous slates were observed here. On closely observing the rocks it was
found that probably two or three episodes of folding have taken place in the past.
Beautiful folds/bends were observed here. Due to iron rich composition, a
reddish brown coating was also observed on the rocks. Intense deformation was
seen at this site and the cleavage observed was slaty cleavage (along with
rhombic cleavage at some places).
GPS Coordinates: Position 2
Latitude = 29°29’39.5”
Longitude = 79°26’47.9”
Elevation= 2316m
Here we observed a reverse fault. We could identify the fault as reverse fault
because on one side of the fault plane anticline fold was observed. It could have only
been possible if hanging wall must have pushed the while moving upward. And as
hanging wall was moving upward it must have been a reverse fault. This type of
faulting is known as Fault propagating folding
The material observed in the fault plane (black color) is termed as Fault Gauge
formed due to fractioning of two walls. This area is highly pulverized. Orange color
was also observed it is due to weathering of iron oxide and reaction with moisture.
On the right side of the fault line a 2 order folding was observed and on the left
side of the fault 3-order folding was observed. Further small kinks could be
observed in the limbs. The white streak of calcite was clearly visible for these kinds
of kinks.
CHARKETH
GPS Coordinates:
Latitude =29°23’07”
Longitude=79°25’49.2”
Elevation= 1857m
It was a part of lesser Himalayas where Tal formation is reported. The rocks
were low grade metamorphic and the place was rich in Dolomite and Shale.
Dolomite layer was thickly bedded and have red patches on them this represents
high iron content. Dolomite was formed by digenesis whereas shale and slate are
formed by metamorphism on mudstone.
We were asked to measure the dip angle and strike direction of some Anticlines
present in that area using Brunton compass. Our group measured all the dip
angles along with the direction and strike direction correctly. For each Anticline
we measured many dip angles in various directions and the largest is assumed to
be the true dip angle and the direction perpendicular to that is strike direction.
We have measured 4 dip angles and strike direction corresponding to each dip.
The angles we measured are 40°, 45°, 38° and 42°. So the greatest among them
45° is assumed as true dip and strike direction is 305° (N 55° W).
There was a debris fall landslide at that place because of high rainfall and being
highly vegetation area. Again the materials are shale and carbonate. There were
full of granular stones on the both sides of the road. Some stones were shiny due
to the presence of iron oxide.
Both Krols and Tals form in marine environment. Closer to the land ->
more organic matter -> mixed up with sediment forming shale ->
(metamorphosised) slate. Different rocks form due to change in depositional
conditions of sea.
In a portion of the location, consecutive layers of slate and limestone were
observed. Slate was easily breakable (incompetent) and on the other hand
limestone was hard (competent layer). On weathering slate with high amount of
iron, oxidized to iron oxide indicating observed brown color. Limestone, rich in
calcium on weathering formed calcium carbonate. Hence white color was
observed. Consecutive layer of different types of rocks (slates and lime stones)
was formed due to the fluctuations of mean sea level. Slates are older and
metamorphosed and on the other hand limestones are younger.
INFRAKROLS.Here was the brown blotting which was due to iron oxidation of
iron bearing minerals such as pyrites. Here we saw a fault, which was
overturned. The chert nodules and shales of the InfraKrol in this areas contain
prokaryotic and eucaryotic orgaic-walled and multicellular cyanobacterial
filaments, coccoids, large acanthomorphic acritarchs and thalophytic algae.In the
uppermost horizon including the Sherwood Member in the Nainital Hills - the
occurrence of small shelly fossils like Caleoloids typicalis, Olivooides alveus,
Spiellus columnorus and Anabarites trisulitos indicate the first appearance of
preservable life forms. Plats are very difficult to preserve here due to easily
debacle organic presence. Gloseoptaryx was the plant which found there before
90 -100 million year ago. It was very nicely folded plant.
TABLE FOR OVERTURNED FAULT
Strike DIP DIRECTION DIP AMOUNT
Position 1 N35°W N54°E 15°
Position 2 N45°W N50°E 13°
Position 3 N35°W N62°E 7°
Position 4 N274°E N5°E 85°
Position 5 N275°E N6°E 87°
Position 6 N260° N350° 45°
CONTACT BETWEEN INFRA-KROLS AND KROLS
In infrakrols 100% slates and more pyrites were present but in krols more lime
stone in form of dolomite and less pyrite was present. There was also a reverse
fault due to compression result in upward movement of hanging wall .A
overturned fold was also there we called it over turned because both limbs was
inclined in same direction. There also exists a fault within the folding which had
displaced the limbs of the folds. AT this place we also observed plunging fold and
tried to calculate plunge angle.
Strike of that fold-N260°, Dip direction-N345°, Dip amount-29°
CONCLUSION
Psychologically I have come to a conclusion that we have crossed the age of
playing with stones and have reached an age of identifying the names to those
rocks. This shows the maturity of mind in the field of Geology. For the 1st time
we have come into the field to study Geology this was a very good experience to
all of us and I wholeheartedly agree that field study stands a step ahead to the
normal laboratory study with samples.
Regarding the course I have learnt the formation of The Great Himalayas
one of the world’s largest mountain ranges. During these excursions we tried to
understand the local geology of areas around Nainital. We also had the
opportunity of applying the basics learned in a previous course on Engineering
Geosciences in field, such as identifying rocks, measuring dip and strike angles
in field using Brunton Compass etc.