Geological fieldwork report

Geological Excursion and Field Work in Chobhar Area
A Report Submitted to Prof. Dr. Tara Nidhi Bhattarai
Samarpan Academy (Institute of Crisis Management Studies) for the Partial
Fulfillment of the internal evaluation
of the Paper CMS-502 Geological Processes and Natural Hazards
Submitted by:
Bhadra Bahadur Singh Thakuri
Masters in Crisis Management Studies
First Semester
28th
April, 2018 Roll No. 4

2
Acknowledgement
We are privileged with an excellent opportunity to have geological excursion and fieldwork in
Chobhar area on 24th
March 2018. To be a good crisis manager, the fair amount of knowledge
about the geological process and its implication on the crisis is essential. In this regard, I would
like to acknowledge the wisdom of Samarpan Academy (ICMS) for selecting such an interesting
and useful subject (Geological Process & natural Hazards) as a part of course curriculum and in
addition, organizing fieldwork to impart practical knowledge.
I am deeply indebted to Prof. Dr. Tara Nidhi Bhattarai sir, faculty of ICMS for his valuable
insights during theoretical classes followed by his presence, conduct and guidance during
geological excursion and field work with tireless efforts despite his busy schedule. He has been
my source of inspiration. I sincerely thank his generosity and greatness.
Similarly, I would like to thank all of my colleagues of ICMS 5th
Batch for their kind
cooperation and generosity during this fieldwork. I would also like ensure that any deficiencies
in this report remain my own responsibilities.
28th April 2018

3
Table of Contents
Acknowledgement ii
Chapter-1 Introduction
1.1 Aim and Objectives 1
1.2 Investigation/ Study to meet the objectives 1
1.3 Selection of excursion site 2
1.4 Map of excursion site 2
1.5 Relevant Literature for study context 2
Chapter-2 Materials and Methods
2.1 Observation method 3
2.2 Experiment method 3
2.3 Descriptive method 3
2.4 Equipments and their uses 3
Chapter-3 Results
3.1 Observing the geomorphic features 4
3.2 Gaining information from topographical map 4
3.3 Observing geological structures & processes 5-6
3.4 Identifying rocks and its characteristics 6
3.5 Attitude measurement 7
3.6 Finding own position on map 8
3.7 Time estimation for point to point walk 9
Chapter-4 Discussion 9-10
Chapter-5 Conclusion 10
Reference 11

4
Chapter 1 Introduction
Geology is the fascinating subject (Bhattarai and Rai, 2015, p. 1) in which we learn interesting
and useful facts about mother earth. The best way of study is observing the aspects of geology in
surrounding areas. As a part of a course requirement, we students of ICMS 5th
batch got an
opportunity to have geological excursion and fieldwork in Chobhar area. We were engaged in
various practices in observing, identifying, experimenting and computing on geological features,
structures, information and attitudes in the close guidance of subject matter expert. To document
the learning achievements of fieldwork in systematic order this report has been prepared.
1.1 Aim and Objectives
The aim of the geological excursion and field work is to impart the practical knowledge to the
students about geological processes and its impact on crisis management.
To accomplish the selected aim the specific objectives are as mentioned below;
1.1.1 To observe and identify the geomorphic features in and around the site.
1.1.2 To handle the equipment like service protractor, Brunton compass and geological
hammers for the purpose of geological study and excursion.
1.1.3 To gain managerial information from the topographical map such as surface elevation
with the help of contour lines and measurement of physical structures with the help of map scale.
1.1.4 Observation, identification and analysis of geological structures like pothole, sink hole,
rock joints, joint plane etc.
1.1.5 To observe the weathering and erosion process.
1.1.6 To identify and observe the character of rocks using dilute hydrochloric acid and
geological hammer.
1.1.7 To measure the attitudes like bearing, strike, dip direction and dip amounts.
1.1.8 To find own position on the map by trisection method.
1.1.9 To estimate the reasonable time to walk from one point to another.
1.2 Investigation/ Study to meet the objectives
The small groups of students were engaged in various objective focused practices (which will be
described in later segments of the report) to achieve the above- mentioned learning objectives. In
each practice, the groups were given tasks to solve themselves relating the theoretical learning in
the classes. The group works were checked and corrected. In addition, some tasks were
demonstrated and briefed by the teacher on the spot. Walk through talk through between teacher
and students were done reaching every part of the site. Students were privileged with close
observation of every geological structures guided by subject matter expert (SME). The features
of rocks were examined by using a geological hammer and diluted HCL.

5
1.3 Selection of excursion site
The field site was Chobhar area which is situated at approximately 14 km distance towards South
West from ICMS. The place is rich in geological features and structures. Easily identifiable land
features can be observed on map and ground. The geological works of Bagmati River in relation
to tectonic activity can be studied. The exposed rocks can be examined and measured. The
diverse landscape in and around the area can be studied with the help of contour line on a map
and observe them on the ground. The place is close to Kathmandu valley and accessible by
mechanical transport up to the site. Hence the site is appropriate for one-day turn round field
work in cost effective manner.
1.4 Map of excursion site
The satellite image from Google map and topographical map of field site are shown here.
Fig. 1.1 Satellite image and topographic map of Chobhar area.
1.5 Relevant literature for study context
The book "Fundamentals of Geological Excursion and Field Work" written by Bhattarai, T.N. &
Rai, S.M., (2015) is referred to set the context of the study regarding geological knowledge and
guidelines for excursion/ fieldwork. Furthermore the book of Keller, E.K, (1999) titled
"Introduction to Environmental Geology" and Tarbuck, E.J., Lutgens, F.K., (2005) "Earth: An
Introduction to Physical Geology" are reviewed.

6
Chapter 2 Materials and Methods
Following multiple study methods were adopted to achieve the objectives of the fieldwork.
2.1 Observation method
Students observed geomorphic features like peak, saddle, slope, spur, river terraces etc.
Geological structures like cut bank, deposit bank, rock formation, joint plane, cracks, bedding
plane and so on and the geological process like chemical weathering by acid rain, physical
weathering by tree roots and erosion/ deposition by river were observed.
2.2 Experiment method
The type of rock, it's age, and weathering probability were experimented with the help of a
geological hammer. The soft sound when banging the rock with a hammer and the scratch lines
on rock indicated that the rocks are softer than steel and weathering chance is high. Likewise, the
experiment of dropping dilute HCL on bedding plane producing Fizz justified that the rock
contains calcium carbonate and it is sedimentary rock particularly limestone.
2.3 Descriptive method
After observation and experiment, our instructor described how the geological processes took
place in past and present influence in future. The impact geological process on crisis
management was the core issue of description.
2.4 Equipments and their use
The various equipments used during fieldwork are their utility is shown in below table;
S. N. Equipments/ materials Use during fieldwork
1. Topographical Map Orientation, locating positions & gaining information
2. Geological Hammer Testing, extracting and crushing rock/fossil samples
3. Brunton Compass Measuring forward/back bearing, strike, dip direction/amount
5. Dilute HCL in a dropper To experiment the type of rock observing a chemical reaction
6. Protractor To measure and plot the grid bearing on the map
7. Notebook, pencil, map
marker, ruler, measuring
tape
Note taking, map marking, measuring map distances and
features on the ground
8. Camera To take photographs
9. Water bottle, sunglass,
and sports shoes
Personal use during fieldwork
Table 2.1 Equipments used during fieldwork.

7
Chapter 3 Results
Various practices were conducted during fieldwork. The results of the field work are described
below with the help of photographs and tables.
3.1 Observation of geomorphic features
Fig. 3.1 Geomorphic features observed from excursion site.
3.2 Information from a topographical map
Students practiced in gaining following managerial information from the topographical map.
S. N. Descriptions Data Method
1. Elevation at the east side of suspension
bridge near Manjushree park
1280
meter
Following the contour lines on a
map
2. Length of the suspension bridge 75
meter
Converting the length from map
to ground with the help of scale
3. Elevation of river bank beneath the east
end of the bridge
1260
meter
With the help of contour lines
Table 3.1 Information gained from a topographical map.
Peaks
SaddleRidgelineSlope
Spur
River
Terrace 3
River
Terrace 2 River
Terrace 1
Cut Bank
Deposition
Bank

8
3.3 Observing geological structures
Below are the photos of geological structures observed at the site.
Fig. 3.2 Photos of geological processes taken at excursion site.
Joint plane parallel to river course Bridge foundation on rock joints
Potholes made of river water pressure Sink holes due to chemical weathering
Bedding plane & pebble imbricationsBase rock & alluvium deposit by river

9
Fig. 3.3 Photos showing chemical & physical weathering.
3.4 Identifying rocks and its characteristics
The experiment using diluted HCL showed that the rocks are sedimentary (limestone) containing
calcium carbonate. The sound and scratch made by geological hammer indicate that the rocks are
softer than steel and high chances of weathering by geological agents.
Fig. 3.4 Photos showing experiment on rock.
Physical weathering by tree rootsChemical weathering by acid rain
Dropping diluted HCL on the rock HCL reaction with calcium carbonate

10
3.5 Attitude measurement
The attitudes of rocks exposed at different places were measured as given in the table.
Obsn
No.
Structure Strike Dip Direction Dip
amountAzimuth Quadrant Azimuth Quadrant
1. Bedding plane & Bed 1500
-3300
S300
E-
N300
W
2400
S600
W 500
-3280
S320
E-
N320
W
2380
S580
W 550
-3250
S350
E-
N350
W
2350
S550
W 350
Table 3.2 Attitude measurement of the rocks.
Fig. 3.5 Photos showing measurement of attitude
Measuring strike on rock B.P. Measuring dip direction on B.P.
Measuring dip amount on bed Plotting grid bearing on map

11
3.6 Finding own position on the map
Observer's position was located on the map by tri-section method. For this three easily
identifiable features on map and ground were taken for reference points. With the help of
Brunton compass, the forward and backward bearing of each feature were read. Adjusting the
declination, the magnetic bearing were converted into grid bearing and plotted on a map with the
help of protractor. The point where the lines reading back bearing of three features contact each
other that is the own position on the map. Below table shows the azimuth bearings of each
reference points.
S. N. Feature Forward Bearing Back Bearing
1. Peak (ht. 1980 m) 2260
0460
2. Last end of Spur (Point C) 1820
0020
3. Hill (Point D) 1460
3260
Table 3.3 Azimuth bearing of the features
Fig. 3.4 Locating own position on the map.
Determining own position on map by tri-section method
41

12
3.7 Time estimation to walk from point A to C
Depending upon the scale of the map, the aerial distance from point A to C is 4.3 km whereas the
ground distance following the road/track is approximately 10 km. The average walking rate of a
healthy human is 5 km/hr hence it takes 2 hours to travel the distance from point A to B.
Chapter 4 Discussion
4.1 Practice 1: Observing geomorphic features. The existing geomorphic features around
the area were formed and deformed due to plate tectonics over geological time. The Bagmati
River is older than the surrounding hills. Due to the tectonic upliftment, the river flow was
obstructed, deposition took place and the giant lake was formed in Kathmandu valley in
geological past. The river is constant erosion agent. Later on, when the uplift stopped or
subsidence took place, the river erosion became much faster and the lake converted to the valley
with drainage. We also observed the multiple terraces formed at the depositional bank of the
river. There is newly existing terrace towards river side of deposition bank.
4.2 Practice 2: Gaining information from the map. A crisis manager can gain
information from the map without going to the field using map reading skill. It helps to assess
crisis situation and make plan e.g. the width of Chobhar George is 80 meter and the information
is that the flood in Bagmati River is carrying 100 meter long trees. We can estimate the possible
crisis of river block.
4.3 Practice 3: Observing geological structure and processes. Various geological
structures like bedding plane, joints, joint plane, pothole, sinkhole and processes like chemical
weathering due to acid rain over limestone and physical weathering due to tree roots were
observed. The alluvium deposit and pebble imbrications in circular & semi-circular shape in far
above bank indicates that once river was at that level. The river flows parallel to the joint plane.
The bridge foundation over the rocks having inclined joints needs rock bolting. Knowing the
structures and processes at the site, a crisis manager can have a good decision regarding
construction, development projects and agricultural activities.
4.4 Practice 4: Identifying rocks & testing its features. The common rocks available in
the area, its hardness, weathering condition and mineral composition were studied which helped
to know the rock formation process and geological location and its best use for human beings.
4.5 Practice 5: Attitude measurement. It's relations between directional features and
horizontal plane measured as a strike, dip direction and dip amount. These attitudes help to get

13
the orientation of any feature containing rock/ mineral and estimate the area of interest for
mining.
4.6 Practice 6: Finding own position and estimating time to walk. To gain information
from map and formulate plan, it is necessary to find out the own position on map. It helps to be
oriented with map and ground as well. Similarly, the distance calculation helps to make plans
and decision to reach from own location to destination point.
Chapter 5 Conclusion
The fieldwork conducted at the geologically rich site remained utmost interesting and useful. We
are benefitted with practical knowledge regarding geological processes and materials on earth
surface as well as in its interior. As students of crisis management, it is necessary to incorporate
the consequences of geological processes in decision making and management. We must be
aware how the events and process in past and present affect the future. Our efforts should be
directed towards the judicious use of resources ensuring sustainable development.

14
References
Bhattarai, T.N., Rai, S.M., 2015. Fundamental of Geological Excursion and Field Work, Second.
ed. Creative Work Nepal, Kathmandu.
Keller, E.K., 1999. Introduction to Environmental Geology. Prentice-Hall, New Jersey.
Tarbuck, E.J., Lutgens, F.K., 2005. Earth: An Introduction to Physical Geology, 8th ed. Prentice-
Hall, New Jersey.
Prepared By:
5th
Batch
ICMS First Semester
Roll No. 4
28th
March, 2018
Members in team work

Geological fieldwork report

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Similar to Geological fieldwork report

Similar to Geological fieldwork report (20)

More from Bhadra Thakuri

More from Bhadra Thakuri (8)

Recently uploaded

Recently uploaded (20)

Geological fieldwork report