A Report On Field Visit To Malekhu

A report on field visit to Malekhu
Preface
Nepal is a land of geological diversities. So the knowledge of engineering
geology is very essential for the engineering structures to be stable and durable
in this region. To provide the students, the basic concept of engineering geology
and geological structures, the Malekhu field visit was extremely necessary
because the students themselves can see everything in front of them, they can
measure themselves various geological parameters and analyze the various
geological structures such as folds, faults, unconformity etc.
This report provides the gist of the Malekhu field visit. Every activity
performed, every data taken, every site visited and every difficulty faced and
each and every results of such site visit are orderly maintained in this report.
The sketches of each and every site along with their photographs, the location of
the site (in terms of chianage), the observations made and the findings of the
site including the techniques used, the description of the geologically vulnerable
zones, their causes, engineering significance and ways of control make this
report very visual and gives the readers a clear ideas about the visit.
Acknowledgement
We would like to express our deep and sincere gratitude to the
Department of Civil Engineering, Pulchowk Campus and especially to the
section of Geology. Special vote of thanks goes to the instructors during the
field visit, namely Prakash sir, Basant sir, Hitendra sir and Shrawan sir, without
which the field visit would have been impossible. They shall be ever credited
for the in depth knowledge of the geology which otherwise would not have
gained!

Also, we are thankful to all the persons who are contributed so
immemorable, knowledgeable and entertaining. All of the friends who were
always with us in the field are thanked for making the field visit a worth time to
have and worth place to be.
Of course, on the course of our stay, Chitwan Triveni Hotel and its owner
helped us in every way to make our stay comfortable, to whom we
acknowledge. All others directly or indirectly helping us to make our field visit
http://s3.amazonaws.com/academia.edu.documents/33984372/…hment%3B%20filename%3DEngineering_Geology_Field_Visit.docx 2/19/16, 8:17 PM
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successful are thanked.
All the references which helped in making our report meaningful and
knowledgeable are thanked. Also a special vote of thanks goes to Microsoft
Company and Bill Gates for making this wonderful Microsoft Word without
which report would not have been possible.
Last but not the least, group E thanks the manufacturer of laptop and
desktop on which this report is prepared!

-Group”E”
Introduction
Geology and civil engineering shared a close and intimate relation with
each other as no foundation can be laid in air, every civil engineering structures
stands on earth’s surface and therefore it’s vita to know about the earth’s
surface, various landforms and factors affecting it which coincides with literal
meaning of geology.
The present era is the era of construction, so civil engineering today not
only deals with construction of structures(buildings, dams, bridges etc) rather it
deals with construction of structures with maximum safety lesser efforts in a
shorter time at a minimum possible price.
For all these factors, we need to know a lot about the existing geological
condition. In the construction site, we need to know about the types of soil and
it’s properties so that we could modify, excavate or replace it as required. We
need to know about the rock underlying it, exposed at the site. We need to know
about the ground water condition, we need to know about the mass movement
and most importantly we need to know about the faults, folds and fractures
present at the site. For all these information, we could go nowhere but study
geology. So geology plays a vital role in civil engineering.
As we have already discussed the importance of geological knowledge,
only theoretical knowledge is lame when we are concerned with civil
engineering which is total practical.
It’s very difficult for us to understand the various geological features such
as beds, bedding plane, their orientation, strike, faults, folds, fractures, and river
morphology but it will become very effective when we see all of them in front
of our eyes. In the beginning phase, when we are just building our geological
knowledge, our basic concept must be very clear for which geological field visit
or trip is essentially required.
In a way, this reports provides us both the above mentioned aspects are
clarified. The readers will have knowledge of various geological features and
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their civil engineering significance through this report.
Location
Malekhu lies on lesser Himalayan region of Nepal. It has peculiar
geological features within a small range of area. The Malekhu V.D.C. of
Dhading district lies about 70 kms south west of Kathmandu valley and is
located at latitude of 27
o
50' 38'' to 27
o
45' 50'' and longitude of 24
o
49' 5'' to 84
o
50' 50’’. It is situated on the bank of Trishuli and Malekhu River. The Trishuli
River is running from the eastern direction to the western direction and the
Malekhu River from south to north which mingles into the Trishuli River. Also,
the Malekhu River has a tributary namely the Apakhola which meets the
Malekhu River at a distance about 3 kms from the Malekhu bazaar. Climatically
Malekhu is a sub-tropical zone. Mainly the rainfall is during the monsoon.
Objectives of field study
❖ To be clear enough about joints, faults and folds.
❖ To estimate, where the bridge site should be selected?
❖ To identify the rock type and its property.
❖ To measure strike of bedding plane.
❖ To measure the dip direction and dip amount of the bedding
planes and joints
❖ To study about the rock mass and its classification on the field.
❖ To study the mass movement.
❖ To understand the River morphology
Methodology
The primary method of collection of data was used in the field
during the field visit to Malekhu. The visit was a very useful tool to help
develop a concept about the geological structures, mass movement, rock mass
analysis and rating.
The primary methods used are:
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❖ Sighting of the field
❖ Sketching of the field in its natural condition
❖ Photograph of the field
❖ Collection of data
❖ Interpretation and analysis of data
Study of Slope instabilities along road
corridor
Mass movement
Mass movement is the detachment of and down slope transport of soil and
rock material under the influence of gravity and accelerated by various factors
especially water. The sliding and flowing of the materials takes place due to
their position and gravitational forces but the mass movement is accelerated
mainly by the presence of water. The main cause of mass movement is the
gravitational force. As when gravitational force acting on a slope exceeds its
resisting force, slope failure (mass wasting) occurs. But various factors like
strength, folding, faulting, jointing, foliation, bedding, soil depth, porosity,
permeability, rock type and soil type play effective role in mass movement.
Types of mass movement
Depending upon mechanism, types of material and rate of movement mass
movement can be classified into mainly three types viz. soil failure, landslide
and debris flow. They can be briefly defined as follows:
Landslides
Descent of a mass of earth and rock down a mountain slope is often known
as landslide. Landslides may occur when water from rain and melting snow
sinks through the earth on top of a slope, seeps through cracks and pore spaces
in underlying sandstone, and encounters a layer of slippery material, such as
shale or clay, inclined toward the valley. The water collects along the upper
surface of this layer which it softens. If the support is sufficiently weakened, a
mass of earth and rock slides down along the well-lubricated layer. Some great
landslide masses move slowly and spasmodically for years, causing little
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destruction.
There are various types of landslides depending upon movements and
materials. They are:
a. Falls
b. Topples
c. Slides
d. Spreads
e. Flows
Debris flow
A debris flow is a fast moving, liquefied landslide of unconsolidated,
saturated debris that looks like flowing concrete. It is differentiated from a
mudflow in terms of the viscosity and textural properties of the flow. Flows can
carry material ranging in size from clay to boulders, and may contain a large
amount of woody debris such as logs and tree stumps. Flows can be triggered
by intense rainfall, glacial melt, or a combination of the two. Speed of debris
flows can vary from 5 km/h to up to 80 km/hr in extreme cases. Volumes of
material delivered by single events vary from less than 100 to more than
100,000 cubic meters. Variables considered important in debris flow initiation
include slope angle, available loose sediment, and degree of land disturbance by
activities such as forest harvesting.
Slope failure
Slope failure is the movement of weathered surface soil layer/rock of steep
slope in small dimension and rapid movement. In this there may be absence of
slip surface. These types of failures occur due to steep slopes, loose soil, and
excavation of rock or soil on downhill side. There are two kind of slope failure.
There are two kind of slope failure. They are (a). Slope failure (b).Rock failure
The preventive measures for the mass movement are:-
1. Retaining structures: These are the walls are rigid walls which
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are used to support the soil mass laterally so that the soil can be
retained at different levels on the two sides. Following are the type
of retaining walls constructed on risky zones for mass movement
prevention:-
2. Gabion wall: Those wall are made by filling the stones in the
wire net. Those wall check the soil material without undergoing
failure due to their flexibility.
3. Stone masonry wall: Those walls are made by joining stones
with the cement concrete.
4. Concrete masonry wall: Those walls are made by mixtures of
aggregates of cement.These structures are only suitable to prevent
small scale of mass movements (mostly landslides).
5. Rock anchoring: In this method an anchor which is made
steel bar or wire is anchored to the sliding soil mass to the bed
rock. However the bond strength between anchor and rock at the
anchor part should be considered beforehand in this method.
6. Pile works: In this method sheet pile of f200-600 mm are
driven through the sliding surface to control landslide movement
directly. This method is employed for urgent and important
locations. They are installed from the center to the lower part of the
landslide block.
Description of mass movement in each location
Location A(chainage 17+00 km, along Trivhuvan highway)
A typical type of mass movement was observed along the Tribhuvan
highway at 17 km chainage.A landslide was seen which showed different
features. Some debris flow as well as the slope failure was also seen.
The factors causing these may be:
a. Stress developed by vehicles and road construction.
b. Due to reduced strength of soil caused by various other
geological factors and violent rainfall.
Measures for remediation:
1. Both gabion wall and the concrete masonry wall at the side
of highway. Crib wall and the check dam were also seen.
2. Rock anchoring was observed was observed about 100 m
ahead which were preventing the movement of sliding mass.
SKETCH AND PHOTOGRAPH
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Figure 1: Location A
Location B(Belkhu khola bridge along Prithivi Highway)
Another location to be observed was Belkhu Khola Bridge. This location
had a bridge which was a new one. However we could clearly see some
reminisces (pillars, old bridge parts) at the sides of existing bridge. Actually
what happened was that the old bridge span was swept away by the flood in
2050 B.S. This was due to the fact that the bridge span was kept below peak
flood level. However the existing bridge span is kept above the peak flood level.
From the study, we came to know that the peak flood level should be
studied before making the bridges and such structures near the rivers.
The main thing to be studied however was the outcrop which was observed
at the right bank of Trishuli River. Amazing thing was that the slope was
vertical but stable. Many things contribute to make the slope stable, such as
there were vegetations in the upper layer of the slope. The shear stress was
balanced in the region, thus stabilizing the slope.
where,
Hence, it was interpreted that the normal stress, friction angle and the
cohesion are high in the slope.
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Figure 2: Location B
Location C (chainage 42 km along Prithivi Highway)
A complex landslide was observed in this area. There were different ways
implemented in the area to avoid further landslide.
The remedies used in this area are:
1. Cascade drainage for surface drainage.
2. Gabion wall for stabilizing continuous moving mass.
3. Stone machinery wall for stabilizing the fixed mass in the bed
rock with weep hole and sub-surface drainage system.
4. Technique of bio-engineering used for which some special types
of plants like sishau, kaher, bakiyino,bhojetro are planted in a proper
way.
Sketch and photograph
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Figure 3:Location C
Location D(chainage 43 km along Prithivi Highway)
Rock slope failure was observed at the chainage of 43 km along the Prithivi
highway from Kathmandu.
Plane, wedge and toppling failure observed in that area. A colluvial fan was
also observed on the slope. The slope was however seemed to be temporarily
stabilized.
Failure mechanisms on rock slope:
There are three failure mechanisms on rock slope on the basis of orientations
of discontinuities with respect to the orientations of hill slope.
Plane failure
When the dip direction of planner features such as joints, beddings or
foliations is at the same direction (±20
◦
) as that of the hill slope or cut slope then
plain failure is possible. However friction angle has also influence in this
mechanism.
Wedge failure
When two planes intersects obliquely across the slope face and their line of
intersection plunges at the same direction as the dip direction of hill slope or cut
slope then wedge failure is possible.
Toppling failure
The toppling failure is possible when the planar features dip opposite to hill
slope or cut slope and the hill slope or cut slope is steep enough than the planner
features.The main causes for such failures in the location might be due to improper
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cutting of rock bed during the road construction.
The preventive measured used in this location are:
a. Gabion walls are placed near the road as check wall and catch wall.
However, the slope has self- stabilized.
Figure 4: Location D
Measurement of attitude of rock bed
Compass
Compass refers to the device used for measurement of angles. In geology,
a magnetic compass is used to find out the attitude of bed, i.e. the dip amount
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and dip direction.
Types of compasses
Clinometers compass
The compass which can measure bearing and orientation with
two sets is called clinometers compass. Since it doesn’t consist the
sprit level, it should be leveled by approximation and may not be
accurate.
Brunton compass:
It consists of sprit level and can measure bearing and inclination
with relatively less error.
Clar compass:
It can read both inclination and bearing at simultaneously. It is
relatively easier to handle.
Digital compass:
The value of the bearing taken are directly displayed as digits so
it is very simple to operate.
Digital PC compass:
This is similar to digital compass. In addition to it, this compass
is directly connected to the computer so there is no need to observe
the data and to note down it in the note book. The taken data are
directly transferred to the computer.
Handling of geological compass:
A geological compass is used to measure the attitudes of the
geological features (strike and dip) and orientation of the slopes. In
the past, the compass was mainly used for measuring the bearing of
object with respect to north and to measure inclination. The main
operation of geological compass consists of opening the compass
carefully, leveling the spirit level and placing the compass on the
planer feature for measurement.
Planar features and attitude of planar features
The planar features of rock consists of rock beds, joint plane and
foliation planes. The orientation of rock beds can be described from the
attitude. Attitude is the three dimension orientation of planar features of
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rock. Attitude of beds or joint plane can be described from strike and
dip.
Strike
Strike is the line formed by intersection of an inclined geological
plane and its own projected horizontal plane.
Dip amount and direction
Dip amount is the angle between geological plane and horizontal
plane which provides inclination of the bed.
And dip direction refers to the direction of the horizontal
projection of the bed. Strike and dip direction are perpendicular to each
other.
Measurements of attitudes of the rocks
Location No.L1:
About 50m far from the old (broken) bridge along Prithivi Highway the data of
rock strata are taken.
S.N. Dip Direction Dip Amount Attitude Plane Remarks
Observed by : Sujit Bhandari
1 S 82O
E 30O
S 82O
E/30O J.P
2 S 75O
W 10O
S 75O
W/10O J.P J.P=Joint Plane
3 S 78O
E 21O
S 78O
E/21O J.P
4 S 04O
E 86O
S 04O
E/86O B.P
5 S 21O
E 71O
S 21O
E/71O B.P B.P=Bedding
Plane
6 S 70O
W 50O
S 70O
W/50O B.P
7 N 56O
W 84O
N 56O
W/84O B.P
8 S 09O
E 86O
S 09O
E/86O B.P
9 S 83O
W 61O
S 83O
W/61O J.P
10 S 87O
W 63O
S 87O
W/63O J.P
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Observed by : Sudeep Paudel
1 S 88O
E 31O
S 88O
E/31O J.P
2 S 64O
W 50O
S 64O
W/50O J.P
3 S 04O
E 87O
S 04O
E/87O B.P
4 N 55O
W 45O
N 55O
W/45O B.P
5 N 56O
W 64O
N 56O
W/64O J.P
6 S 81O
W 85O
S 81O
W/85O J.P
7 S 20O
E 85O
S 20O
E/85O B.P
8 N 78O
E 21O
N 78O
E/21O B.P
9 S 14O
E 82O
S 14O
E/82O J.P
10 N 19O
E 84O
N 19O
E/84O B.P
Observed By : Simpson Lamichhane
1 S 18O
E 84O
S 18O
E/84O B.P
2 S 20O
E 85O
S 20O
E/85O B.P
3 S 12O
E 87O
S 12O
E /87O B.P
4 S 14O
E 82O
S 14O
E/82O B.P J.P=Joint Plane
5 S 20O
E 84O
S 20O
E/84O B.P
6 S 11O
E 83O
S 11O
E/83O B.P B.P=Bedding
Plane
7 S 18O
E 90O
S 18O
E/90O J.P
8 S 16O
E 78O
S 16O
E/78O B.P
9 N 85O
E 10O
N 85O
E/10O J.P
10 N 89O
W 36O
N 89O
W/36O J.P
Observed By : Tshreya Bhattarai
1 N 84O
W 47O
N 84O
W/47O J.P
2 S 16O
E 78O
S 16O
E/78O B.P
3 N 56O
E 76O
N 56O
E/76O B.P
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4 S 82O
W 64O
S 82O
W/64O B.P
5 S 18O
W 90O
S 18O
W/90O J.P
6 N 19O
E 84O
N 19O
E/84O J.P
7 S 17O
E 87O
S 17O
E/87O B.P
8 S 11O
E 86O
S 11O
E/86O B.P
9 N 56O
E 84O
N 56O
E/84O B.P
10 N 60O
W 79O
N 60O
W/79O B.P
Observed by : Sudip Thapa
1 S 14O
E 89O
S 14O
E/89O B.P
2 S 75O
W 52O
S 75O
W/52O J.P
3 N 89O
W 36O
N 85O
W/36O J.P
4 S 19O
E 75O
S 19O
E/75O B.P
5 N 86O
W 52O
N 86O
W/52O J.P
6 N 85O
E 10O
N 85O
E/10O J.P
7 S 85O
W 86O
S 85O
W/86O J.P
8 S 04O
W 84O
S 04O
W/84O B.P
9 S 68O
W 67O
S 68O
W/67O J.P
10 N 89O
W 58O
N 89O
W/58O J.P
Observed by : Sudesh Dahal
1 N 55O
W 79O
N 55O
W/75 J.P
2 S 69O
W 66O
S 69O
W/66 J.P
3 N 20O
W 79O
N 20O
W/79 B.P
4 S 11O
W 83O
S 11O
W/83 B.P
5 N 85O
W 10O
N 85O
W/10 J.P
6 N 00O
W 54O
N 00O
W/54 J.P
7 S 20O
E 85O
S 20O
E/85 B.P
8 N 78O
E 21O
N 78O
E/21 J.P
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Figure 5: Fold
9 N 02O
E 88O
N 02O
E/88 B.P
10 N 20O
W 59O
N 20O
W/59 J.P
STUDY OF GEO-STRUCTURES
Structure geology deals with the mechanism and types of deformation of
rock or earth’s crust due to distribution of stress generated through various
geological processes. Structural geologists use microscopic analysis of oriented
thin sections of geologic samples to observe the fabric within the rocks which
gives information about strain within the crystal structure of the rocks. They
also plot and combine measurements of geological structures in order to better
understand the orientations of faults and folds in order to reconstruct the history
of rock deformation in the area. In addition, they perform analog and numerical
experiments of rock deformation in large and small settings.
Compressive, tensile and shear stress produce strain in the structures in the
earth’s surface. The deformation may be elastic, brittle, ductile; which
determines which structure is to be formed. The structures may be of following
types :
FOLD
The term fold is
used in geology
when one or a stack
of originally flat and
planar surfaces, such
as sedimentary strata, are bent or curved as a result of plastic (that is,
permanent) deformation. Fold is the ductile deformation caused due to
compressive stress. Fold most often occurs well inside the earth’s surface.
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Figure 6:Folds and its types
The general types of folds are:
• Anticline: linear, strata normally dip away from axial center, oldest
strata in center.
• Syncline: linear, strata normally dip toward axial center, youngest
strata in center.
• Symmetrical: limbs form mirror image of each other, both limbs
dip at equal angle in opposite direction, axial plane is veritcal.
• Unsymmetrical: limbs donot form mirror image of each other,
both limbs dip at unequal angle in opposite direction, axial plane is
oblique.
Engineering Significance:
1. For the foundation of dam in a large fold, upstream is more
favourable than the downstream.
2. In fold, there is more stress in the zone of hinge line than the other
zones.
3. In synclinal aquifer, the underground water potential is higher and
is adverse in case of anticlinal fold.
LOCATION
L6,
FIELD OBSERVATIONS
An anticline asymmetric fold was seen in the site. The existence of fold
was confirmed by the sighting of hinge line and the different dipping of the rock
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Figure 8: Normal and Reverse fault
in the boulder seen. Also, fold in the area was confirmed by the dipping of the
rock masses on different directions from the location.
FAULT:
A fault is a planar fracture or discontinuity in a volume of rock, across
which there has been significant displacement in the plane parallel to the
fracture plane. Fault is the result of brittle deformation due to tension,
compression and shear
stress. Large faults
within the Earth's crust
result from the action of
tectonic forces. Energy
release associated with
rapid movement on
active faults is the cause
of most earthquakes.
A fault line is the
surface trace of a fault, the line of
intersection between the fault plane and the Earth's surface.Since faults do not
usually consist of a single, clean fracture, geologists use the term fault zone
when referring to the zone of complex deformation associated with the fault
plane.The two sides of a non-vertical fault are known as the hanging wall and
footwall. By definition, the hanging wall occurs above the fault and the footwall
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Figure 9:Dip slip and Strike slip faults
occurs below the fault.
Geologists can categorize faults
into three groups based on the sense of
slip:
1. a fault where the relative
movement (or slip) on the fault
plane is approximately vertical is
known as a dip-slip fault
2. where the slip is
approximately horizontal, the
fault is known as a transcurrent or strike-slip fault
3. an oblique-slip fault has non-zero components of both strike and
dip slip.
Also, on the basis of genetic classification, the fault may be normal fault
and reverse fault.
1. Fault zones are not strong and cannot resist the heavy loads and
stresses, such as dams and high raise buildings.
2. As there are non-homogeneous rock masses in the zone of fault,
an extra calculation and expenses are needed in the case of such areas.
3. There is chance of water to come out from the fault, which even
more increases the risk of having more faults in this zone.
4. Violent faults may even cause earthquake and damage the
engineering structures.
LOCATION
L7, located at a distance of 200 m from old bridge on the left bank of
Malekhu River.
FIELD OBSERVATIONS
Small scale fault was seen in the site. The evidence of the fault was that of
the presence of powder gauge and breccia. Due to high heat and temperature,
the gauge was seen along with the breccia, which provides the direct evidence
of the existence of the fault.
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Figure 10: Fault as seen in the field
THRUST
A thrust is a type of fault, or break in the Earth's crust across which
there has been relative movement, in which rocks of lower stratigraphic position
are pushed up and over higher strata. They are often recognized because they
place older rocks above younger. Thrust faults are the result of compression
forces.
Thrust faults typically have low dip angles. A high-angle thrust fault is
called a reverse fault. The difference between a thrust fault and a reverse fault is
in their influence. A reverse fault occurs primarily across lithological units
whereas a thrust usually occurs within or at a low angle to lithological units. It
is often hard to recognize thrusts because their deformation and dislocation can
be difficult to detect when they occur within the same rocks without appreciable
offset of lithological contacts.
If the angle of the fault plane is low (generally less than 20 degrees from
the horizontal) and the displacement of the overlying block is large (often in the
kilometer range) the fault is called an overthrust. Erosion can remove part of the
overlying block, creating a fenster (or window) when the underlying block is
only exposed in a relatively small area. When erosion removes most of the
overlying block, leaving only island-like remnants resting on the lower block,
the remnants are called klippen (singular klippe).
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The engineering significance of a thrust is same as that of a fault but a
thrust extends over a larger zone and is more likely for re-occurrence due to its
low angle. Even some thrusts keep on being active with very small velocities.
Thus it should be taken in care before designing any civil engineering
structures.
FIELD OBSERVATIONS:
The Malekhu region also contains the Main Central Thrust (MCT), also
known as Mahabharat thrust extending throughout the Mahabharat range. The
evidence of the thrust has been laid by sighting the metamorphic rocks on the
earth’s surface along with the younger rock types on the surface. The younging
sequence has been reversed in the region giving indirect evidence of thrust.
An inverted metamorphic field gradient associated with a crustal-scale
south-vergent thrust fault, the Main Central Thrust, has been recognized along
the Himalaya for over 100 years. A major problem in Himalayan structural
geology is that recent workers have mapped the Main Central Thrust within the
Greater Himalayan Sequence high-grade metamorphic sequence along several
different structural levels.
PHOTOGRAPH
Figure 7:Fold seen in the field
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JOINT
The term joint refers to a fracture in rock where there has been no
movement in the plane parallel to the plane of fracture of one side relative to
the other. This makes it different from a fault which is defined as a fracture in
rock where one side slides laterally past the other. However, there could be a
perpendicular displacement to the plane of fracture. Joints normally have a
regular spacing related to either the mechanical properties of the individual rock
or the thickness of the layer involved. Joints generally occur as sets, with each
set consisting of joints sub-parallel to each other.
Joints are classified based on the attitude of joint w.r.t. the attitude of the
bedding and on the basis of the orientation of joint sets.
Geometric classification
Dip joint: strike of a joint parallel to the dip of bedding.
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Strike joint: strike of a joint is parallel to the strike of the bedding.
Oblique joint: strike of a joint makes an angle with the strike of the bedding.
Genetic classification:
Mural joints: joints on the massive igneous rocks, three sets of joints
perpendicular to each other
Columnar joints: joints formed on volcanic igneous rocks such as basalts,
vertical prominent planes breaking the rocks into hexagonal prismatic columns
Sheet joints: one set of prominent joints found in massive igneous rocks
Tension joints: joints developed due to tensile forces acting on the rock, found
commonly on the
PHOTOGRAPH
Figure 12: Joints
ENGINEERING SIGNIFICANCE
1. The joints represent the areas where the rock mass has been
fractured. So, the rock mass may detach at the point and are
unnecessary in light of the engineering construction.
2. The reservoirs, tunnels and dams should not be constructed in
these regions as there are chances of water leakage.
Page 22 of 51

Figure 13:parallel unconfirmity
3. There are chances of ground water seepage in the areas of
joints.
4. As the areas of joints are the regions of breakage, the site is
weak and heavy constructions such as dams, high raise
buildings, etc. shall not be constructed in these areas.
Joint planes are more harmful than the fault planes but less harmful than
the bedding planes. However, the attitude of the joint planes have greater
significance in the construction within these palces.
UNCONFORMITY
An unconformity is a buried erosion surface separating two rock masses or
strata of different ages, indicating that sediment deposition was not continuous.
In general, the older layer was exposed to erosion for an interval of time before
deposition of the younger, but the term is used to describe any break in the
sedimentary geologic record.
The rocks above an unconformity are younger than the rocks beneath
(unless the sequence has been overturned). An unconformity represents time
during which no sediments were preserved in a region. The local record for that
time interval is missing and geologists must use other clues to discover that part
of the geologic history of that area. The interval of geologic time not
represented is called a hiatus.
The formation of unconfirmity may be attributed to three main processes
like erosion, deposition and tectonic activities. Its development involves the
following stages:
1. The formation of the older rocks.
2. Upliftment and surfacial erosion of the older rock.
3. Again, the formation of younger succession of beds after long
interval above the surface of erosion.
There are three types of unconformity:
Parallel Unconfirmity
Parallel
unconformity is a
type of unconformity in which strata are parallel;
there is little apparent erosion and the
unconformity surface resembles a simple bedding
plane. It is also known as disconfirmity,
nondepositional unconformity or
pseudoconformity.
Page 23 of 51

Figure 14: angular unconfirmity
Figure 15: Nonconfirmity
Angular unconfirmity
Angular
unconformity is an
unconformity where horizontally parallel strata of
sedimentary rock are deposited on tilted and
eroded layers, producing an angular discordance
with the overlying horizontal layers. The whole
sequence may later be deformed and tilted by
further orogenic activity.
Non confirmity
A
nonconformity exists
between sedimentary
rocks and
metamorphic or
igneous rocks when
the sedimentary rock
lies above and was
deposited on the pre-existing and eroded metamorphic or igneous rock.
Namely, if the rock below the break is igneous or has lost its bedding by
metamorphism, the plane of juncture is a nonconformity.
LOCATION
L3,
FIELD OBSERVATIONS
Unconformity was seen and identified in the field. An unconformity
existed between the bed rock and the depositional layer. The deposited layer
was loose and consisted of small stone particles and sand, deposited over an
intact bed rock, exposed at that place. The difference in the depositional time
period was clearly seen which confirms the presence of unconformity.
Metamorphic
rocks
Figure 11: Evidence for the thrust
Sedimentary
rocks
Page 24 of 51

STUDY AND IDENTIFICATION OF
ROCKS
Rock is defined as naturally forming, hard and compact solid aggregates or
assemblage of minerals forming crust of the earth. The branch of geology that
deals with the study of various aspects of the rocks, such as their mode of
formation, composition and occurrence is called petrology.
The rocks are classified as following on the basis of their mode of
formation:
A. Igneous Rock
Page 25 of 51

Figure 17: Igneous rock
Figure 18: Sedimentary rock
The rocks formed by the cooling and
solidification of molten mobile mineral called
‘magma’ by the crystallization are called
igneous rock. The process of formation of
igneous rock is called magmatism.
Igneous
rocks are formed when molten magma cools
and are divided into two main categories:
plutonic rock and volcanic. Plutonic or
intrusive rocks result when magma cools and
crystallizes slowly within the Earth's crust (example granite), while volcanic or
extrusive rocks result from magma reaching the surface either as lava or
fragmental ejecta (examples: pumice and basalt) .
[1]
B. Sedimentary Rock
The rocks formed by the process of
accumulation, compaction, cementation,
and consolidation of the sediments are
called sedimentary rock. The sediments
are formed by the weathering of old
rocks, igneous, metamorphic and even
sedimentary.
Sedimentary rocks are formed by
deposition of either clastic sediments,
organic matter, or chemical precipitates (evaporites), followed by compaction
of the particulate matter and cementation during diagenesis. Sedimentary rocks
form at or near the Earth's surface. Mud rocks comprise 65% (mudstone, shale
and siltstone); sandstones 20 to 25% and carbonate rocks 10 to 15% (limestone
and dolostone).
[1]
C. Metamorphic Rock
Page 26 of 51

Figure 19: Metamorphic rock
The rock formed due to the change in the
nature and properties of the pre-existing rock is
called metamorphic rock. When igneous rocks
and metamorphic rocks are subjected to high
temperature and stress for very long period of
time, they gradually change their form and
evolve as a new form of rock known as
metamorphic rock. The process of formation of
metamorphic rock is called metamorphism
(examples: slate, marble, diamond, etc)
Identification Of Rocks
Location no.L4
About 200m from the hanging bridge over the Trishuli River along Thopal
Khola i.e. in between location L2 and the hanging bridge. Following things we
observed in this location
Sample no.1
S.N. Physical
Properties
1 Sample
number
01
2 Colour Greyish
3 Texture Non crystalline
4 Structures Foliation plane/slaty cleavage
5 Grain size Fine
6 Sp. Gravity Low to medium
Page 27 of 51

7 Acid test No reaction
8 Mineral
comp.
9 Origin/rock
type
Metamorphic rock
10 Engineering
properties
Low strength
Low blastability
Low drillability
11 Identification Slate: saltic cleavage
12 Uses Roofing, in electrical industry as switch board, bases and
various turned or shaped parts due to its insulating
property.
13 Attitude of
the rock:
S 009o
E/84o
Location no.L5
Sample no.2
S.N. Physical Properties
1 Sample number 02
2 Color Dirtywhite
3 Texture Crystalline
4 Structures Bedding plane
5 Grain size Medium
6 Sp. Gravity Medium to high
7 Acid test Vigorously reacts with HCl in powder form
Figure 16: Unconformity (Loose soil in the left and bed rock on the right)
Page 28 of 51

8 Mineral comp. Calcite
9 Scratch test Scratched by hammer
10 Origin/rock type Sedimentary
11 Engineering propertiesHigh strength
High blastibility
High drillability
12 Identification Dolomitic limestone
13 Uses Raw material for cement,
aggregates
14 Attitude of rock S 0080
E/ 850
Location no.L8
Sample no. 3
Amphibolites
1 Sample number 03
2 Color Greish black
4 Structures/cleavage Massive/Foliation plane/slaty
5 Grain size Fine to medium
6 Sp. Gravity High
8 Mineral comp. Amphibolite group
9 Origin/rock type Metamorphic
10 Engineering properties High strength
Page 29 of 51

High blastibility
High drillability
11 Identification Amphibole groups
12 Uses Can be used as good quality aggregates
Location no.L8:
Sample no 4
Phyllite
1 Sample number 04
2 Color Silver white
4 Structures/cleavage Foliation plane/slaty
5 Grain size Medium to coarse
6 Sp. Gravity Medium
8 Mineral comp.
10 Engineering properties Low strength
High drillability
Low blastability
Page 30 of 51

11 Identification Phyllite
12 Uses Pavements, dry wall and slabing
Location no.L9
Sample no. 5
Quartzite
1 Sample number 05
2 Color Dirty white
4 Structures/cleavage Foliation plane/slaty
5 Grain size Fine
6 Sp. Gravity Medium to high
8 Mineral comp. Quartz
Low drillability
High blastsbility
11 Identification Quartzite
12 Uses For making reeling in home
applications, building stone, road
metal, concrete aggregates
13 Attitude of rock S0180
E/780
PHOTOGRAPH
Figure 20: Sample no. 5
Page 31 of 51

Location no.L10
Sample no. 6
1 Sample number 06
2 Color Silver white
4 Structures Foliation plane
5 Grain size Fine to coarse
Page 32 of 51

6 Sp. Gravity Low to medium
8 Mineral comp. Garnet, chlorite, quartz, horn blend,
talc
10 Engineering
properties
Low strength, incompetent, harmful
and undesirable rock
11 Identification Garnitiferous Schist
12 Uses Rock foundation, building stone,
aggregate for concrete, road material
13 Attitude of the rock S30o
E/46o
PHOTOGRAPH
Figure 21: Sample no.6
Location no.L11
Sample no. 7
Page 33 of 51

1 Sample number 07
2 Color White
4 Structures Foliation plane
5 Grain size Coarse
6 Sp. Gravity High
8 Mineral comp. Quartz, plagioclase, biotite, muscovite
Low drillability
High blastability
11 Identification Augen Gneiss
12 Uses as flooring mill and for building stone
or material
PHOTOGRAPH
Page 34 of 51

Location no.L12
Sample no. 8
1 Sample number 08
2 Color White
4 Structures No plane of mineral orientation,
no bedding plane
5 Grain size Coarse
6 Sp. Gravity High
8 Mineral comp. Orthoclase, biotite,quart, plaeoclase,
muscobite
11 Engineering
properties
High strength
High blastability
Low drillability
Isotropic
12 Identification Granite
13 Uses As aggregates, foundations in the
construction and as slab
PHOTOGRAPH
Page 35 of 51

Figure 23:Sample no.8
Location no.L14
Sample no. 9
1 Sample number 09
2 Color Whitish
4 Structures Bed plane/Foliation plane
Page 36 of 51

5 Grain size Coarse
6 Sp. Gravity High
7 Acid test Vigorously react in powder form
8 Mineral comp. Calcite
11 Engineering
properties
Medium strength
High drillability
High blastability
12 Identification Marble
13 Uses Used in cement factory,
In construction of civil engineering
structures
14 Attitude of the rock S15 o
E/ 87 o
PHOTOGRAPH
Page 37 of 51

River Channel Morphology
River patterns, or general shapes, depend on the geologic zone and the
climate of the location. There are three river patterns: meandering, braided, and
straight. A meandering pattern follows a winding, turning course. A braided
pattern has connected channels that resemble a hair braid. Some river patterns
are simply straight channels. Meandering and braided are the most common
patterns. Braided and straight patterns are usually located in the mountains or
hills below the headwater zone of rivers, while meandering patterns is located in
the middle and mouth zones of most rivers.
Meandering river morphology
A meandering river has looping bends of different sizes along its valley.
Each bend is the result of sediment depositing on the inside of the bend. The
topography of meandering river area is characterized by moderate relief,
medium gradient and velocity lower tthen straight river channel morphology. As
sediment deposits gradually build up, a point bar forms on the inside of the
bend. The point bar pushes the river flow against the outside bank of the bend,
eroding the bank opposite the point bar. Eventually the bend becomes so sharp
that the river bypasses it, cutting a straighter path. The arc of the bend is left
behind as the river moves past. The arc may form an oxbow lake, a pool of
water enclosed by the arc and riverbank. A meandering river’s bed is usually
covered with sand, while the floodplain is filled with silt and clay. Since the
energy level of such river is medium, the erosional rate and the depositional rate
of sediments is comparatively equal. Due to this phenomenon, the channel
shifting is prominent in such type of river system.
Braided river morphology
Braided rivers look completely different from meandering rivers. The
topography of the braided river area is characterized by low relief. The gradient
is low, area widned, and water flow with low velocity. They have many
channels that are constantly changing position because of frequent changes in
flow rate and sediment supply. The channels of a braided river change course
frequently, so the river’s water may cover the entire floodplain on a regular
Page 38 of 51

basis. The sediments of braided rivers are usually gravel and cobbles.
Sometimes a meandering river may change into a braided river in the middle
zone if the supply of sediment increases as a result of farming or grazing
activities in the watershed.
Straight river morphology
This type of river follows a straight path. The topography of the area is
characterized by steep relief. The slope of the river is also high causing the flow
velocity of water high , since the energy level of such river is high erosional rate
is intensely higher than the deposition of sediments. Deep scouting along the
path is higher than the side cutting. Straight rivers are not common. They are
typically located in canyons in mountainous areas or exist as the result of
engineering structures that force a river into a straight course.
Features developed by river channel morphology
Alluvial Fans and Cones
These are cone shaped accumulation of stream debris that is commonly
found at places where small intermittent streamlets coming down from hills enter
the low lands. The apex of such a deposit points up hill and its slope may range
from almost flat to as much as 50. When the slope of the deposits is below 10, the
alluvial deposit is known as alluvial fan, and when it is from 10-50, the deposit is
known as alluvial cone. Alluvial fans and cones show contrasting patterns in
distribution of fragments and particles of various sizes at their apices, peripheries
and in the main body. Further repeated accumulations over an initial fan or cone
contribute to its considerable growth. Alluvium is usually very porous and will be
compressible if rich in clay and permeable if composed of gravel, sand or silt.
Flood Plain Deposits
Floodwaters are invariably heavily loaded with sediments of all types. When
these waters overflow the banks and spread as enormous sheets of water in
surrounding areas, their velocity gets checked everywhere due to obstructions. As
a consequence they deposit most of the load in the form of a thick layer of mud, so
commonly seen after major flood. Since such a process may get repeated year after
year, the low lying areas surrounding major rivers are actually made up of the
layers of mud deposits laid after a number of floods. These are generally level or
plain in nature and extensive in area and are called Flood plains. All the plain
around major rivers are actually flood plains. These are invariably very fertile in
nature and hence have been supporting population. Two major types of flood
plains known as convex flood plains and flat flood plains are known.
Deltas
Deltas are defined as alluvial deposits of roughly triangular shape that are
deposited by the rivers at the points where they enter into the sea. Herodotus first
used this term for the deposits of the river Nile at its entry into the Mediterranean
Sea. Deltas are very complex in their structure. A number of fractures are involved
in their formation, evolution and modification.
Oxbow Lake:
Page 39 of 51

Figure 25: Formation of ox-bow lake.
The
isolated curve
or loop
shaped part of
meandering
river often
contains some
supplies of
water known
as oxbow
lakes in the shape of curve.
Floodplain
Floodplain is a flat region of a valley floor located on either side of a
river channel. A floodplain is built of sediments deposited by the river that
flows through it and is covered by water during floods when the river overflows
its banks. During most floods, just a portion of the floodplain is covered with
water and only during infrequent, very large floods is the whole floodplain
covered. Floodplains tend to develop on the lower and less steep sections of
rivers.
River channel morphology in foodplain
River channels in floodplains adopt two kinds of patterns: meandering
and braided. Meandering rivers consist of a single main channel that bends and
loops. In some cases, the channel is so winding that the length along the channel
is several times the straight-line distance along the river valley. Braided rivers
have numerous distinct channels that repeatedly divide and then merge again
downstream. While a meandering channel occupies only a small part of its
floodplain at any one time, a braided river occupies much of the floodplain over
the course of a year.
Both patterns migrate across the floodplain, removing sediments from
their path and depositing them elsewhere. A braided river reworks the sediment
in its floodplain very frequently as the various individual channels continually
shift position. In meandering rivers, sediment is eroded on the outside of bends
and on the downhill side of traverses and deposited on the inside of bends and
Page 40 of 51

on the uphill side of traverses. Over time, this causes meander loops to migrate
downstream. If the movement of one meander loop overruns the next one
downstream, then a meander cut-off, or chute, is formed. This causes the course
of the channel to be shortened as the two meander loops join. The abandoned
meander loop is gradually isolated as sediment is deposited at each end by the
water flow in the main channel. This process eventually leads to the creation of
an ox-bow lake. On average, about 290 km (about 180 mi) of the channel of the
Mississippi River is abandoned through the formation of meander cut-offs every
100 years, but the overall channel length is not reduced because there is a
compensating enlargement of other meanders.
Many interrelated factors determine the form taken by river channels and
it is not precisely understood why some river channels have a meandering
pattern and others are braided. Meandering channels are more common where
the floodplain sediments are sand, silt, and clay. Braided channels are more
common where the floodplain sediment is mostly gravel or where there is an
increase in channel steepness. A braided pattern also tends to be favored if the
amount of water flowing in the river is highly variable or if the banks are easily
eroded and can provide abundant sediment to the channel.
Engineering significance of different types of river channels
As we well know that the civil engineers have to deal with varieties of the
river channel morphology for the construction of different structures as well as
availability of the construction material. If we consider straight river channel
morphology, then construction of masonry bridge foundation on river channel is
not applicable as deep scouring is intense along the path, whereas, the straight
river channel has low side cutting, in such case arch bridge can be a good
option. Similarly the construction of run off hydropower dam is an option. In
meandering river if the bridge is constructed in a curve portion then the
foundation on the striking band may be affected. Instead the site of the bridge is
selected on the straight potion of the meandering river.
Whereas, depending upon the construction material available like granite
boulders, gravity dam can be constructed in this type of morphology like
Kulekhani Hydropower Dam. In braided river condition, a span of bridge is
high with many pillars on the river path. In low land braided river morphology,
the hydropower project is impracticable, due to low gradient and high
sedimentation problem.
Location
L2, about 300 m from Malekhu suspension bridge towards Dhading Beshi.
Sketch and Photograph
Page 41 of 51

Figure 26: River Channel Morphology
ENGINEERING GEOLOGICAL DATA
COLLECTION
Engineering geological data
There are some factors whose condition in case of rock are observed and recorded
in order to determine the strength of the rock for laying foundation on it is simply
known as engineering geological data. These data also helps us to determine the
present condition and the nature of the rock. The data was collected in location
no.1 about 50m from damaged bridge on the left side of Malekhu River.
Importance of engineering geological data
Purpose specific geological data collected from field (rock mass) which can
be quantified and used as design parameter. It is quantities diagnosis of an area. It
must be purpose specific. Site investigation is the investigation of particular area
for specific purpose data collection. It is very essential to draw any engineering
geological map or to solve any geological problems.
Page 42 of 51

We always deal with a rock mass not only with a block of rock. Rock mass
means intact rock with its discontinuities. In many cases, the technicians are in
dark in this aspect. He collects a piece of sample and takes it to the lab and
concludes his result. This is not a correct way to publish any geological decision.
In fact, it is much more important to know the entire rock mass up to our concern.
Parameters of engineering geological data
Rock type:
1. Sedimentary
2. Igneous
3. Metamorphic
Rock strength:
a. High
b. Medium
c. Low
Weathering grade
a. Fresh weather (w0)
b. Slightly weathered (w1)
c. Moderately weathered (w2)
d. Highly weathered (w3)
e. Completely weathered (w4)
f. Residual soil (w5)
Rock Quality Designation (R.Q.D)
It is expressed in percentage. The expression for RQD has is:
RQD=115-3.3*Jv
Where Jv = Joint volume. i.e. number of joint per unit volume.
Spacing of discontinuity
It is expressed in cm and all the discontinuity is taken under considered area.
Aperture or separation of discontinuity
1. Tight (<1cm)
2. Open (expressed in cm, all the data are taken)
3. Wide (>30cm)
Infilling materials
➢ Sand/slit/clay/calcareous material
Persistence ( Continuity of discontinuity)
Roughness of discontinuity
1. Smooth
Page 43 of 51

2. Rough
3. Undulated
Number of joint set
These are the number of parallel or nearly parallel sets of the joints in the rock
mass.
Orientation of joint set
Expressed including dip amount and dip direction, (i.e. dip amount/dip direction)
Ground water condition
1. Dry
2. Dripping
3. Seepage
4. Flowing
5. Damp/wet
Rock mass classification system
The rock mass classification system is the system of evaluating the composition
and characteristics of the rock mass. The foundation stands on the rock and the
properties of rock affects the stability of foundation. The problems related to these
things can be solved using the rock mass classification system. This system helps
to estimate the strength and deformation properties of the rock mass. There are
four methods of rock mass classification.
Description of Rock mass classification system
Terzaghi’s Rock mass classification
This classification is the earliest reference which is the descriptive classification.
The rock with no joints: intact rock
The rock with little strength along bedding surfaces:
stratified rock.
Rock mass jointed but cemented: moderately jointed rock
Jointed rock mass without any cementing of joints: blocky
and seamy rock
Rock reduced to sand sized particles due to weathering:
crushed rock
Rock with clay: squeezing rock
Rock squeezes primarily from mineral swelling: swelling
Page 44 of 51

rock.
Rock quality designation index (RQD)
D. U. Deere introduced a rock mass classification system based on the qualitative
estimate of rock mass quality from drill core logs.
But in absence of core logs ,
,
which is suggested by Palmstom (1982) where Jv is sum of the number of joints
per unit length of all discontinuities sets or simply the volumetric joint count.
Bieniawski’s geomechanics classification
Bieniawski in 1976 published the details of rock mass classification called
the geomechanics classification and widely known as rock mass rating (RMR)
system. During the study of rock mass classification this method has been adopted.
Six parameters are widely used in this system.
1. Intact rock strength
2. RQD
3. Spacing of discontinuities
4. Orientation of discontinuities
5. Condition of discontinuities
6. Ground water condition
Different rating value has been provided to different parameters and the
sum of all these parameters gives the final rating. The value of rating provides the
class of the rock.
Rock mass classification based on RMR
Class no.
Rating value
Rock quality
I 100-81 Very good rock
II 80-61 Good rock
III 60-41 Fair rock
IV 40-21 Poor rock
V <21 Very poor rock
Rock tunneling quality index (Q value)
Barton et. al (1974) proposed this theory. The value of Q varies on the
logarithmic from 0.001 to 1000.
Q value is defined by:
Page 45 of 51

Q= (RQD*Jr*Jw)/(Jn*Ja*SRF)
Where,
❖ RQD= Rock quality designation
❖ Jr= joint roughness number
❖ Jw= joint water reduction factor
❖ Jn= joint set number
❖ Ja= joint alternation number
❖ SRF= stress reduction factor
Engineering geological data observed in the field
Location no. 04:
Rock mass classification by RMR system (rock mass rating)
Sample no. 1
S.N.
Parameters Properties rating
Remarks
1.Rock type Sedimentary
2nd
class
Rock mass,
Good rock
2.Rock strength Medium to high 12
3.Weathering W1 5
4.R.Q.D. test 88% 17
5.Spacing of
discontinuity (cm)
26,17,13,8,3,8,16,7,13
8
6.Separation Tight 6
7.Infilling materials Silt in traces 6
Page 46 of 51

8.Persistence 2.5-3.5m 4
9.Roughness Rough 5
10.
No. of joint set 2
11.
Orientation of joint sets S850
W/590
N850
W/59 0
5 Ground water
condition
Dry 15
Total 78
Sample no.2
S.N.
Remarks
2nd
class
Rock mass,
Good rock
2.Rock strength Medium to high12
3.Weathering W2 3
4.R.Q.D. test 88.6% 17
5.Spacing of
discontinuity(cm)
9,20,40,18,2,56,45
8
7.Infilling materials Clay 2
8.Persistence 0.8-2m 4
9.Roughness Very Rough 6
10.
No. of joint set 3
11.
E/610
N640
W/48 0
S180
E/800
Page 47 of 51

5 Ground water
condition
Seepage 10
Total 68
Sample no.3
S.N.
Remarks
1st
class
Rock mass,
Very
Good rock
2.Rock strength High 15
3.Weathering W1 5
4.R.Q.D. test 82% 17
5.Spacing of
discontinuity(cm)
10,7,2,3 15
7.Infilling materials No 6
8.Persistence 1-2m 4
9.Roughness Rough 5
10.
No. of joint set 3
11.
E/840
N630
W/76 0
N900
W/460
5 Ground water
condition
Dry 15
Total 88
Page 48 of 51

Photograph

Objectives of rock mass classifications
Identify the most significant parameters influencing the
behavior of a rock mass.
Divide a particular rock mass formulation into groups of similar
behavior – rock mass classes of varying quality.
Provide a basis of understanding the characteristics of each rock mass
class
Relate the experience of rock conditions at one site to the conditions
and experience encountered at others
Derive quantitative data and guidelines for engineering design
Provide common basis for communication between engineers and
geologists.
Engineering significance of rock mass classifications:
Improving the quality of site investigations by calling for the
minimum input data as classification parameters.
Providing quantitative information for design purposes.
Enabling better engineering judgment and more effective
Page 49 of 51

communication on a project.
Conclusions:
At last, we have concluded that Malekhu proves to be a good place for the
study and interpretation of the geology, its components and its significance in the
field of engineering. Actually, Malekhu, even small in area, contains large amount
of geological phenomenon and hence it can provide broad knowledge for the
learners.
Along Malekhu River, we found sedimentary rock and gradually
metamorphosed from Phyllite to crystalline schist and along the way to Dhading, it
gradually metamorphosed to lime stone to Phyllite and then to slate.
Every major bed was dipped in north direction. This proved the tectonic
movement is along the way from south to north. As the region lies in the zone of
Main Central thrust (MCT), there are evidences of different types of tectonic
activities such as unconformity, fold, fault, thrust, etc. within a small area.
Besides this, we have learnt different methods of geological data collection
through geological compass. By, the rivers channel morphology, we had known
how the river flows, what are the factors affecting erosion and deposition and how
it occurs. Also, we were able to gain board knowledge on the different landforms
formed by rivers.
Consequently the field trip was so much hard but in reality it had provided us
an opportunity to get closer to the real experience of practical study in the days to
come. This trip provided with a vivid knowledge of the geology which would
otherwise be hardly possible.
REFERENCES:
Page 50 of 51

➢ Data collected during the field visit.
➢ Sketches drawn and photo taken in the field.
➢ www.geology.edu.np
➢ www.wikipedia.com
➢ www.google.com
➢ Journal of the Geological Society; 2008; v. 165; issue.2
➢ Britannica 8.0(2009)
➢ Microsoft Encarta
➢ Engineering Geology:
By Ghimire, P. Chandra;
Dhar, M. Singh
➢ A Text Book of Engineering Geology
Kesavul, N. Chenna
Page 51 of 51

A Report On Field Visit To Malekhu

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