Geology

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EVEREST ENGINEERING COLLEGE
AFFILIATED TO POKHARA UNIVERSITY
Sanepa, Lalitpur
A
Report
On
Geology Tour to Malekhu
Submitted by
Prashant Joshi(31)
Rawbee Dahal(32)
Raju Rayamajhi(33)
Ramsudist Yadav(34)
Ranjit Mandal(35)
Roshan Sah(36)
Submitted to
Department Of Civil Engineering
Date:2076/10/17

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ACKNOWLEDGEMENT
We would like to express our deepest appreciation to all those who provided us the
possibility to complete this report. Our special thankful to the administration of
Everest Engineering college, Head of civil Engineering Department Er.Prashant
Thapaliya and for managing tour and providing the required materials in the field.
It’s the golden opportunity to us to workout with our subject teacher Anil Ghimire
and Mr.Aadesh Budhathoki for their insightful and scholarly guidance to
successfully complete this field work.
Finally, we would like to thank all the staffs, drivers and others who directly or
indirectly helped us to successfully complete the field work.
 Group Members
Prashant Joshi
Raju Rayamajhi
Roshan Sah
Ramsudist Yadav
Ranjit Mandal
Rawbee Dahal

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TABLE OF CONTENTS
Contents PageNo.
INTRODUCTION ………………………………………………………………………………………………………… 4
➢ STUDY AND INTERPRETATION OF RIVER CHANNEL MORPHOLOGY…………………………………. 4-8
• RIVER CHANNEL MORPHOLOGY
• TYPES OF RIVER CHANNEL PATTERN
• FEATURES DEVELOPED BY THERIVER CHANNEL
• PHOTOGRAPH OF LOCATION
➢ STUDY AND INTERPRETAION OF GEOLOGICAL STRUCTURE……………………………………………… 8-15
• INTODUCTION
• FAULTS
• FOLDS
• JOINTS
• Bedding
➢ STUDY AND IDENTIFICATION OF ROCKS AND MINERALS ……………………………………………………. 16-25
• INTRODUCTION
• IGNEOUS ROCK
• SEDIMENTARY ROCK
• METAMORPHIC ROCK
• SAMPLES OF ROCKS
➢ HANDELING OF GEOLOGICAL COMPASS AND………………………………………………………………… 26-30
MEASUREMENT OF ATTITUDES OF GEOLOGICAL PLATES
• STRIKE
• DIP
• DIP DIRECTION
• GEOLOGICAL COMPASS, DROPPER,HAMMER
➢ CONCLUSION……………………………………………………………………………………………………………. 31
➢ REFERENCE……………………………………………………………………………………………………………… 32

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Introduction
Report on geological field visit to Malekhu, Dhading district organized by the Department of
Civil Engineering,Everest Engineering College dated 2076/11/07.It was conducted in order to
study about rocks, river channel morphology and structure of earth.
Objectives
 Study and interpretation of river channel morphology
 Study and interpretation of geological structure
 Study of rocks and minerals in hand specimen
 Handling of geological compass and geological hammer
Location of study area
The location of study was Malekhu, dhading district. It is about 75km. west of Kathmandu
valley.
1. Study and interpretation of river channel morphology
Geological agents:
Any phenomenon which changes earth crust are geological agent. Due to oxogenous (outer) and
endogenous (inner) process structure of land surface like mountains, hills, valleys, plains occurs.
The exogenous process are those which derive their energy from external sources.Geological
agents like wind, running water, glaciers, sea waves and underground water etc causes change in
structure .Activities of geological agents include processes like gradations,degradations,
aggradation and weathering.
A. River Channel Morphology:
The terms river morphology are used to describe the shapes of river channels and how they
change over time. The morphology of a river channel is a function of a number of processes and
environmental conditions, including the composition and erodibility of the bed and banks (e.g.,
sand, clay, bedrock); vegetation and the rate of plant growth; the availability of sediment; the
size and composition of the sediment moving through the channel; the rate of sediment transport
through the channel and the rate of deposition on the floodplain, banks, bars, and bed; and
regional aggradation or degradation due to subsidence or uplift. The study of river morphology is
accomplished in the field of fluvial geomorphology. When the river flows in its way it follows
the definite path, the path followed by the river during its flow is called river channel.

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Figure:River Morphology
B. Types of river /River channel pattern:
1. Straight river:- When the river flows in the straight path due tohigh energy level this type of
river is called straight river.
Figure:Straight River System
2.Meandering river:- In this type of flow, the river follows the path like as snake's movement.
In valley region, the river follows the meandering path. Erosion and deposition take place side by
side in the same time.
Figure:Meandering River System

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3.Braided:-In this type of flow, the river follows multiple Channels. Deposition is predominant
in this flow. The braided river tends to be very wide and relates shallow. The river follows this
type of path in Terai region.
Figure:Braided River System
C. Features developed by the river channel:-
Depositional landforms :
Higher Terrace
It is the land formed by the river as it was flowing in these areas in the past history. The higher
terrace is over the high flood level of the river in present. There may be finer and coarser
material layers alternately in the higher terrace.
Middle Terrace
As its name it is the middle part of the higher and lower terrace. This terrace will also over the
high flood level of the river.
Lower Terrace (Flood Plain)
During floods a river overflows its bank and submerges the adjacent low-lying areas where
deposition of alluvial material takes place. A wide belt of alluvial plain formed in this way on
either side of a stream, is called 'flood plain'.
Channel Bar
Many rivers are forced to rope a part of their load along their beds, especially in the flatter
regions along their course. Most commonly the deposits so formed tale the shape of long narrow
ridges called channel bars. Since they are made up of sand, they are also called sand bar. The
river will flow from both side of the channel bar. They are temporary in nature because an
increase in velocity, the river may cut down and take the sand along with it.

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Alluvial Fans:
The alluvial material, which flows down from mountains, accumulates at foothills where the
stream enters a plain. The deposition occurs due to abrupt change in the gradient of river valley.
Such deposits spread out in the shape of flat fans and are called “alluvial fans”. Usually the
coarse material is dropped near the base of the slope while finer material is carried further out on
the plain. Alluvial fans from many adjacent streams along a mountain may merge to form a long
wedge of sediment called “alluvial aprons”.
Point Bars
In meandering rivers, sediment deposits occur as point bars. The point bars are the crescent
shaped deposits, which occur at inside bends of a river channel.
Deltas:Deltas are deposits built at the mouths of streams. The deltas are usually triangular in
shape with their apex pointed upstream. When a stream enters an ocean or lake, the currents of
the flowing water dissipate quickly. This results in the deposition of the series of sedimentary
layers, which make up the delta. The material of most deltas is well sorted and many deltas are
uniformly graded.
Location 1st
.We studied the river channel morphology of the Trishuli-Thopal confluence from the higher
terrace of the river located about 500m. NE towards Dhading Besi along old track from the
suspension bridge. There was channel bar in the left side of the river. The discharge of the
Trishuli river was high with compared the Thopal river. There was side bar in the right bank of
the river. At the confluence point there was erosion band in the right side of the river. There was
an island at the confluence of these two rivers. The site study of the field fortified us with the
knowledge about the morphology of the river, the activities of the river, various landforms
formed by the river cutting, deposition and erosion. Moreover the site provided us with the
knowledge about the appropriate site for the construction of the bridge, i.e. the bridge must be
constructed where the effect of river cutting is the minimum and it should be somewhere near the
deposition bank so that we can easily get the constructions required. The site must also have a
strong foundation bed to resist the impact due to river.
Features observed at the site were-
1.Meandering river type
2.Still water present in some part of river.
3. Rock island forms at the junction of Trishuli- Thopal Khola.
4.Erosional and depositional bank in Trishuli river

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5. Point bar deposit in Trishuli river.
6. Large and wide striking bank.
An Image of Trishuli and Thoppal Khola confluence
2. Study and interpretation of geological structure
Introduction
Structural geology is a subfield within geology which focuses on the study of geological
structures, with the goal of learning how, when, and why they formed. There are a number of
applications for structural geology, ranging from determining where valuable mineral resources
might be buried to assessing land to determine whether or not it is safe to build on.
Practitioners in this field usually have a bachelor's degree in structural geology, and they may
have pursued graduate work as well.
•Primary structures
–Primary structures are original features of sedimentary or igneous rocks resulting from
deposition or emplacement.

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–It gives an ultimate goal to understand the total history of a deformed rock and not just its
deformational history.
–It also help to understand that the processes of deposition and deformation are not
necessarily isolated in time
•Secondary structures
–Secondary structures are formed after the formation of rock due to different types of
stresses. Different geological structures are:-
1. Faults
2. Folds
3. Joints
4. Thrust
Faults
Fault is a fracture in the earth's rock units along which there has been an observable amount of
movement and displacement. Unlike folds which form predominantly by compressional stress,
faults result from either tension, compression or shear. In order to correctly describe a fault, it
is essential to understand its components:
1- The fault plane: Is the plane of dislocation or fracture along which displacement has
occurred. The fault plane therefore separates one or more rock units into two blocks.
2- The Hanging wall and footwall blocks: If the fault plane is not vertical, then the block lying on
top of the fault plane is known as the hanging wall block, whereas that lying below this plane is
known as the footwall block.
3- The downthrown and up thrown blocks: The downthrown block is the one that has moved
downwards relative to the other block, whereas the up thrown block is that which registers an
upward relative movement.
4- The Dip of the fault plane is the angle of inclination of the fault plane measured from the
horizontal plane perpendicular to its strike.
5- Fault Throw: Is the vertical displacement of a fault.
6- Dip slip: Is the amount of displacement measured on the fault plane in the direction of its
dip.

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7- Strike slip: Is the amount of displacement measured on the fault plane in the direction of its
strike.
8- Net slip: Is the total amount of displacement measured on the fault plane in the direction of
movement.
N.B. In measuring the slip or throw of a fault, the displacement has to be measured using the
same surface of the same unit affected by that fault.
Types of Faults
1- Normal fault: Is a fault in which the hanging wall appears to have moved downwards relative
to the footwall (i.e. downthrown block = hanging wall block).
2- Reverse fault: Is a fault in which the hanging wall appears to have moved upwards relative to
the footwall (i.e. upthrown block = hanging wall block). Because the displacement in both
normal and reverse faults occurs along the dip of the fault plane, they may be considered types
of dip slip faults.
3- Thrust fault (or thrust): Is a reverse fault in which the fault plane is dipping at low angles (<
45°). Thrusts are very common in mountain chains (fold and thrust belts) where they are
characterized by transporting older rocks on top of younger ones over long distances.
4- Strike slip (wrench, tear or transcurrent) fault: Is a fault in which the movement is horizontal
along the strike of the fault plane.
5- Oblique slip fault: is one in which the displacement was both in the strike and dip directions
(i.e. the displacement has strike and dip components). Keep in mind that an oblique slip fault
can also be either normal or reverse. From this classification of faults, it can be seen that
normal faults result predominantly from tensional stress, reverse faults and thrusts from
compression (or shear), and strike slip faults from tension, compression or shear. The
engineering significances of fault are as follows:
•Faults are the region where dislocation of ground has occurred in the past due to deformation
and where such dislocation cannot be entirely ruled out in future.
•The faulted rocks will form weak foundation despite the fact that the rock originally might
have been strong.
•The shear of fault zone will be a easy pathway for water and cause leakage if left untreated in
dams and reservoirs.

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•Fault planes with easy pathway for groundwater creates problem if encountered along the
highway or tunnel alignment.
•The fault zone once lubricated by water may slip further and prove critical for foundation and
abutments.
•Fault gouge and breccias may create additional problems and they have to be cleared to the
sound bedrock for construction in the site.
•Major fault zones are prone to landslides due to fragile earth material and may cause problem
during construction of various projects.
•The presence of faults, their type and extent and their effect on the project area can be
ascertained by engineering geological map and geophysical data.
•The number, size and inclination of shear zone should given consideration.
•Ideally, projects are to be located far from an active fault and never on the active faults.
•If the site couldn’t be relocated the treatment of the shear zone extensive excavation of the
sheared material and back filling with cement grouting may be a solution to the problem.
•Many major faults may be associated with earthquakes so the project site should also be
considered with respect to the seismic zoning of the country.
•Even if the evidence of the study shows that the sheared zone will have no movement during
the lifespan of the project, some factor of safety should be considered while constructing in the
sheared zone.
Figure:Fault

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Fold:
Wavy undulation on the surfaceof the earth is known as fold. The bending of rock strata is due to
the compressional forces acting from opposite directions.Folds result due to ductile deformation
of rocks.
Engineering Significance of fold:
•Fault planes are weak zone
•Water makes the fault weak
•Some cracks act as channel which creates severe groundwater problem
•Shaking in fault may collapse the civil engineering structures
•Fault can cause landslides
•Fault zones are weak, porous, unstable, incompetent and runserious rick of occurrence of
faulting.
1- Hinge line: Is the line of maximum curvature on a folded surface. The hinge line almost
always coincides with the axis of the fold defined as a line lying in the plane that bisects a fold
into two equal parts.
2- The axial plane is an imaginary plane dividing the fold into two equal parts known as limbs. It
is therefore the plane which includes all hinge lines for different beds affected by the same fold.
3- The crest of a fold can be considered the highest point on a folded surface. The trough is the
lowest point on a folded surface.
4- The inter-limb angle: Is the angle between two limbs of the same fold. It is measured in a
plane perpendicular to that of the fold axis.
5- The angle of plunge of a fold is the angle between the fold axis and the horizontal plane,
measured in a vertical plane. The direction of plunge of a fold is the direction in which the fold
axis dips into the ground from the horizontal plane.
6- The median surface: Is the surface that passes through points where the fold limb changes its
curvature from concave to convex.
7- The amplitude of a fold: is the vertical distance between the median surface and the fold
hinge, both taken on the same surface of the same folded unit.
8- The wavelength of a fold system is the distance between two consecutive crests or troughs
taken on the same folded surface.

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Classification of folds
Folds may be classified based on the direction of dip of their limbs, the inclination of their axial
planes, the value of their interlimb angle, their plunge, and their general shape and effects on the
thickness of the folded layers. In order to describe a fold correctly, one may have to use more
that one of these classifications; e.g. recumbent anticline, open syncline, tight plunging
anticline,.... etc.
Identification of fold:
Local scale fold are directly observe in the field in railways cutting, hill cutting during road
construction, excavation of tunnels as well as drilling of rocks beds for certain purpose. Large
scale fold are recognized in the field by plotting the attitudes of the beds or foliation planes by
preparing geological map and obtaining cross-section.
Figure:Folds
Joints
Joints are fractures in the rocks characterized by no movement along their surfaces. Although
most joints are secondary structures, some are primary, forming at the time of formation of the
rocks.
Types of joints
1- Columnar joints: Are joints that form in basalts. When the basaltic lava cools, it contracts
giving rise to hexagonal shaped columns.
2- Mud cracks: Are joints that form in mud. As the mud loses its water, it contracts and cracks.
3- Secondary joints: Are joints that form in rocks as a result of their subjection to any form of
stress (compression, tension or shear). Joints that are oriented in one direction approximately

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parallel to one another make up a joint set. Rocks often have more than one set of joints with
different orientations, which may intersect, and are then known as joint systems. Note that
tensional stress usually results in one set of joints,whereas compression may form more than one
set.
4- Sheet joints: Are joints that form in granitic rocks in deserts causing them to break into thin
parallel sheets. These joints form when the rocks expand as a result of the rapid removal of the
overlying rock cover, possibly due to faulting or quarrying. This process is called exfoliation.
Engineering significances
The engineering significances of joints are as follows:
•The selection of sites for dams and reservoirs and alignment of tunnels and highway through
require very thorough investigation of joints for arriving at safe and economic design.
•Joints are always considered as a source of weakness of the rocks and as a pathway for the
leakage of water through the rock.
•Both these properties of joints destroy the inherent soundness of the rock to a great extent.
•If a rock forming the foundation of a dam or reservoir happens to be heavily jointed and the
region is one of low water table, the risk of leakage of water from under the dam or from
reservoir may be of substantial magnitude demanding very heavy cost for treatment of rocks.
•If the roof and side rocks in the case of tunnel are much fractured, slippage of rock along these
fractures and leakage of water may cause many troubles.
•A large joint dipping into the highway cut is the site of potential landslide.
•Jointed rocks easily get lubricated in the presence of water and start sliding or falling form the
original places of occurrence.
Figure: Joint Sets

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Bedding:
The primary surface in a sedimentary rock has separating beds with different composition,
texture, color, etc. A plane of separation, along which the rocks has a tendency to split or fracture
parallel to bedding.
Figure:Bedding

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Study and identification of rocks and Minerals in the field
Introduction
Minerals, quite simply, are the building blocks for making rocks, and a rock is made up of one or
more minerals. When you look at a rock and see different colors, those colors are minerals that
make up that specific rock. There are over 3,000 named minerals; however, there are really only
about 30 minerals that people who are not geologists will come across or need to concern
themselves with.There are four criteria that must be met in order for something to be called a
mineral:
• Not formed from the remains of plants or animals; that is, inorganic
• Naturally occurring, not man-made
• Has the same chemical makeup wherever it is found (Ex: Quartz is always SiO2)
• Has a crystalline structure, which means that it has a specific repeating pattern of atoms.
If all four of the criteria are not met, the substance is not a mineral. Therefore, “minerals” made
in a lab are not true minerals because they did not occur naturally.
Here are a few tests that geologists rely on to identify what minerals they are looking at.
Color – Color is a very common way to try to identify a mineral; however, it should not be used
on its own. Because any mineral can be any color, you cannot use color alone to identify a
mineral. Color can merely help you. (Or, sometimes, confuse you!)
Shape – Minerals form in certain shapes based on the elements that make them up. Some
minerals, such as quartz, only form in one particular shape. Others, such as calcite, can be found
in multiple shapes. Sometimes shape isn’t enough and you need to use other tests to help you
identify a mineral.
Hardness – How hard or soft a mineral is can tell you right away what mineral it could or could
not be. The hardness of minerals is based on the Mohs Hardness Scale, which ranges from 1-10,
1 being the softest and 10 the hardest.
Streak – The streak of a mineral is simply the color of a powder that’s left behind when the
mineral is scratched along a white, ceramic, unglazed tile. Even if the color of the mineral itself
changes from one specimen to another, the streak color is always the same.
Luster – Luster simply means the way that light reflects off a mineral. Light can make a mineral
look very dull or as shiny as a diamond. There are many other tests that geologists use; however,
the tests listed above are usually sufficient for the amateur, and can help you identify the mineral.

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There are 3 types of rocks:-
1.Igneous Rock
2.Sedimentary rocks
3.Metamorphic rocks
Igneous Rock
These types of rocks are formed by the solidification of magma either under the surface of earth
or over it. These are of three types according to the solidification process.
Plutonic Rock: - The rocks, which are formed underneath the surface of the earth, are called the
plutonic rocks.
Volcanic Rock: - The rocks, which are solidified on the surface of earth, are called volcanic
rocks.
Hypabyssal Rock: - The rocks, which are solidified on the way of extrusion process, are called
hypo basal rocks. Igneous rocks are commonly identified in the field by the study of their
interlocking crystallization of a number of mineral grains. Igneous rocks are generally hard,
massive, compact, having no bedding plane and interlocked grains. It usually contains much
feldspar. By the study of these properties we identified the igneous rocks in the field. e.g.
Granite - generally equigranular texture, light color appearance
Gabbro - coarse grain and dark color
Dolerite - containing dark minerals in good proportion with medium grain sized
Sedimentary rocks
These rocks are derived from pre-existing rocks through the process of erosion, transportation
and deposition by various natural agencies such as wind, water, glacier etc. The loose sediments
undergo compaction and form resulting products as sedimentary rocks. According to the mode of
transportation the sedimentary rocks are divided into threedifferent types.
Clastic Rocks: - The rocks which are formed by deposited mechanically are known as clastic
rocks.
Chemical Deposits:-The rocks which are formed by chemical precipitation are known as
chemical deposits.
Organic Deposits:-The rocks which are formed by deposited organically are called organic
deposits.

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Sedimentary rocks are identified in the field by the study of different layers, which are originally
bedded or laminated under suitable conditions. There may be the impression of fossils in
sedimentary rocks. The colour and the grain size of the rocks may be different in different layers.
By the study of these properties also the rocks may be identified. e.g.
Conglomerate - grain size greater than 2 mm
Sandstone - grain size is equal to sand (i.e. 1/16 mm –2 mm),
quartz is common
Clay stone - formed by deposition of clay, shale is common example
Metamorphic rock
These are formed by alteration of alignment, texture, structure, chemical composition etc. in pre-
existing rocks due to the action of temperature, pressure and chemical reaction. Metamorphic
rocks are generally hard and having of interlocking grains.
· Contact Metamorphic
· Dynamic Metamorphic
· Dynamo Thermal
· Metasomatic
Metamorphic rocks are distinctly distinguished from other types of rocks by the development of
features like cleavage, foliation, schistosity and by the presence of such minerals which are
known to be of metamorphic origin. Metamorphic rocks often exhibit an interlocking texture of
the constituent minerals grains. Thus these rocks are basically identified in the field on the basis
of color, texture as well as structure. e.g.,
Slate - slate cleavage
Phyllite - soapy feeling
Schist - rough, irregular and undulated plane, unequal growth of minerals
Gneiss - band of contrast colour, composition and texture (mica band)
Sample no 1.
1. Color: light gray
2. Texture: non-crystalline

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3. Structure: foliation plane
4. Grain size: fine
5. Mineral composition:
- Quartz
- Feldspar
- Muscovite
- Biotite
-chlorite
6. Rock type: metamorphic rock
7. Rock name: slate
Uses
1. It is use flooring and roof covering due to the presence of slaty cleavage.
2. It is used as aggregate.
Figure:Slate
Location:
Latitude:27°48’443N
Longitude:84°50’11”E
Sample no 2.
1. Color: White
2. Texture: Crystalline

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3. Structure: bedding plane
4. Grain size: Fine
5. Acid/hammer test: - reacts with acid and mono-mineralic so hammer test can be done.
6. Mineral composition: calcite
7. Rock type: sedimentary
8. Rock name: limestone
Uses:
1. Use in making cement
2. Use for making statue
3. Use as construction material
Figure:Limestone
Sample no 3.
1. Color: Bluish grey
3. Structure: Bedding plane
4. Acid/hammer test: -
-Slowly react with acid but reacts rapidly with power

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-scratches by hammer
5. Mineral composition: Dolomite
6 Rock type: Sedimentary
7. Rock name: Dolomite
Uses:
- Use for making cement by mixing with limestone
Figure:Dolomite
Location: About 800m from the malekhu bridge towards south west along the upstream of
Malekhu River on the right side of bank.
Sample no. 4
1. Color: Silvery gray
2. Texture: crystalline
3. Structure: foliation plane/slaty cleavage.
4. Grain size: fine
5. Acid/hammer test: doesn’t react with acid and cannot be done hammer test due to multi-
minerallic.
6. Mineral composition: Quartz, feldspar, mica(muscovite, chlorite,sericite) and other clay
minerals
8. Rock name: Phyllite
Uses: In filling material, roofing, flooring.

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1. Cannot be used in road aggregate
2. Cannot be used in road foundation
3. Cannot be used in Gavin wall.
Figure:Phyllite
Location:
Latitude:27°49’34”N
Sample no: 5
Location: About 1000m from the malekhu bridge along the upstream of Malekhu River on the
right side of bank.
1. Color: yellowish gray
2. Texture: crystalline
3. Structure: foliation plane
4. Grain size: fine
5. Acid/hammer test: doesn’t react with acid and can be done hammer test due to mono-
minerallic.
6. Mineral composition:
- Quartz
8. Rock name: slate
Uses

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1. Use as aggregate.
2. Use in foundation material.
3. Use for decoration purpose.
Figure:Slate
Sample no: 6
Location: About 1000m from the malekhu bridge along the upstream of Malekhu River on the
right side of bank.
1. Colour: Dark Grey
2. Texture: Non-crystalline
3. Structure: foliation plane/Schistocity cleavage
4. Grain size:fine
5.Acid/hammer test: doesn’t react with acid and cannot be done
hammer test due to multi-minerallic.
6.Mineral composition:biotite,Quartz,fdeldspar,mica.
8. Rock name: schist
Uses:Used for flooring, gap in walls(retaining wall) .

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Figure:schist
Sample-7:
1. Color: White with Black spot
3. Structure: Massive (random orientation of minerals).
4. Grain size: coarse
5. Acid /hammer test: doesn’t react with acid and cannot be done hammer test due to multi-
minerallic.
6. Mineral composition: biotite,Quartz,feldspar,muscovite,
tourmaline and other mineral.
7. Rock type: Igneous rock
8. Rock name: Granite(Xenolyth)
Uses:
Used for flooring, as polishing stone and for construction
Location:

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4. Handling of geologicalcompass and measurementof attitudes of geological
plats
There are a number of different magnetic compasses used by geologists to measure orientation of
geological structures, as they map in the field, to analyze the geometry of bedding planes, joints,
and/or metamorphic foliations and lineations. A functional field compass for geological field
work should have the following attributes:
1. Must be lightweight and portable - can be carried on a belt loop or neck land yard.
2. The compass should be able to provide a precession of 1 degree for bearings.
3. The compass should have magnetic declination adjustment mechanism.
4. The compass should have a clinometer to allow the measurement of slopes and structural
information such as dip and plunge.
Strike:
An imaginary horizontal line in any horizontal plane is called strike. Strike is the horizontal
direction of slope. More precisely, strike can be defined as the direction of a line formed by the
intersection of the bedding(or foliation) with a horizontal plane. In simple term, strike is the
extension of a bed or it is perpendicular to the dip direction.
Figure:Strike
Dip:
The inclination of the bed is called its dip or it is the acute angle between the bedding and a
horizontal plane. Dip line represents the maximum inclination of a bed or foliation plane. It is the
value of angle given by zero of inner graduation of a geological compass, which coincides with
the angle from 0 to 90 when the bubble spirit is at the middle.

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Fig:Dip Angle
Dip direction:
It is the direction of inclination of a bed or slope of mountain or foliation plane. It is measured by
Brunton Compass, holding its north towards the direction of inclined beds or foliation planes. Its
is the value given by the north pointer of the geological compass when compass pointer is
perpendicular to the structural plane.
Orientations of planar features or portions of surfaces by:
Strike, dip, and dip direction; or Dip and dip bearing...
Figure:Dip Direction

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Given data are:
S.N Strike Direction Dip angle
1 276 N 185 N 86 0
2 210 N 81 N 62 0
3 300N 90 N 76 0
4 180 N 125N 87 0
5 200 N 170 N 65 0
6 225 N 110 N 500
Where;
N= North Side

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INSTRUMENTSUSED
1.Brunton Compass
These are the most commonly used type of the geological compass. Since strike, dip and dip
direction are measured only using a rotating level, dip measurements are unaffected by magnetic
fields. We should measure the strike, dip angle and dip direction separately using this compass. It
consists of the levels so measurement is more accurate.
Figure:Brunton Compass
2.GeologicalHammer
A geologist's hammer, rock hammer, rock pick, or geological pick is a hammer used for splitting
and breaking rocks. In field geology, they are used to obtain a fresh surface of a rock to
determine its composition, bedding orientation, nature, mineralogy, history, and field estimate of
rock strength. In fossil and mineral collecting, they are employed to break rocks with the aim of
revealing fossils inside. Geologist's hammers are also sometimes used for scale in a photograph.
The hammer also serves as an extension of the senses, permitting the geologist to perceive the
rock's granularity, soundness, and resistance to fracturing that may be relevant to its use
oridentification.
Figure:Hammer

31
Conclusion:-
In geological field visit of Malekhu area for two days we were able to know about the practical
knowledge about geology. We became able to recognize the geological structures like fold, fault
joint etc. We also know about the study of different type of rocks with its classification, different
properties and engineering significance also. We also learn to measure the rock’s strike dip
amount and dip direction of the bedding plane by using the geological compass (brunton). We
know the handling of geological compass and geological hammer and used it for various
practical purpose. River channel morphology was studied in detail and its features like activities
of river, type of river channel, land forms developed by the river and river channel Morphology
at the Trishuli-Thopal Confluence.
 Group Members

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REFERENCES
 www.geology.com
 www.wikepedia.com
 Enginnering Geology website.
 Data collected during Field Visit
 Photo taken in the field

Geology

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