TECHNICAL REPORT

ON

STUDENT INDUSTRIAL WORK EXPERIENCE SCHEME (SIWES) TRAINING

PROGRAMME

AT

SHOP NO 19 EMMANUEL PLAZA BUKURU BYPASS JOS SOUTH PLATEAU

STATE.
NAME: DANJUMA MANCHANG HARUNA
MATRICULATION NUMBER: UJ/2020/NS/1024
PROGRAMME: GEOLOGY
DATE: MARCH – SEPTEMBER

DEPARTMENT OF GEOLOGY, FACULTY OF NATURAL SCIENCES

UNIVERSITY OF JOS.

BEING A REPORT SUBMITTED TO THE SIWES COORDINATOR IN PARTIAL

FULFILMENT OF THE REQUIREMENTS FOR THE STUDENT INDUSTRIAL WORK
EXPERIENCE SCHEME AT WAKDEE MINES LIMITED, JOS, PLATEAU STATE
 CERTIFICATION
This is to certify that DANJUMA MANCHANG HARUNA of matriculation number
UJ/2020/NS/1024 completed this report based on his six (6) months Student
Industrial Working Experience Scheme (SIWES) carried out at WAKDEE MINES
LIMITED – JOS.

...................................... ………………………………………..
DANJUMA MANCHANG HARUNA DATE
STUDENT

.............................................. ............................................
MR. EMMANUEL GWOTT DATE
INDUSTRIAL BASED SUPUPERVISOR

............................................. .............................................
DR. RAYMOND I. DASPAN DATE
HEAD OF DEPARTMENT

............................................. ..............................................
..
DR. JANET YAKUBU DATE
SIWES COORDINATOR
 APPROVAL
This is to certify that this work has been read and approved by the
undersigned as meeting the requirements for the Student Industrial Work
Experience Scheme (SIWES) Training Programmed at WAKDEE MINES Limited,
Jos, Plateau State.

............................................. .............................................
DANJUMA MANCHANG HARUNA DATE
STUDENT

............................................. .............................................
MR. EMMANUEL GWOTT DATE
INDUSTRIAL BASED SUPUPERVISOR

............................................. .............................................
DR. RAYMOND I. DASPAN DATE
HEAD OF DEPARTMENT

............................................. .............................................
DR. JANET YAKUBU DATE
SIWES COORDINATOR
 DEDICATION
I would like to dedicate this report to the Almighty God, for His infinite mercies, sufficient
grace and the blessings He bestowed on me throughout the SIWES Program. I also dedicate
this report to my lovely family; we stood by throughout the course of my industrial training.
May God bless you all for your support, prayer and encouragement.
 ACKNOWLEDGEMENT

My sincere and profound appreciation goes to the almighty for his love and protection and
also for supplying me with good health and sound mind during the period of my SIWES
programmed. I appreciate the entire community of the University of Jos, Plateau State and
the SIWES Directorate for the opportunity given me to acquire quality industry experience
while yet in school. I must also mention the efforts of my Departmental SIWES Coordinator,
Dr. (Mrs.) Agati Janet Yakubu, for all her assistance and sacrifice to make this program a
reality, not forgetting my institution-based supervisor Mr. Caleb Mangai for his patience,
assistance and sacrifice. I acknowledge the efforts of the Managing director, Mr. Wakdung
Wambutda for giving me the opportunity to do my SIWES at his company for imparting me
with practical knowledge in groundwater exploration and borehole. I want to express my
appreciation to my Industrial-based supervisor Mr. Emmanuel Gwott for his intellectual
support during our work together, not forgetting the management and staff of WAKDEE
Mines Limited who supported me and made my stay at the company worthwhile. I am
indeed grateful to all my lecturers in the department of geology for adequately preparing
me academically for the challenges I encountered during the period of my industrial
training. Finally, I would like to appreciate my beloved parents, Mr. And Mrs. HARUNA
TIMLOH, whose contributions and supports to my life are impactful.
 TABLE OF CONTENTS
Title page - - - - - - - - - -
Certification - - - - - - - - -
Approval - - - - - - - - - -
Dedication - - - - - - - - - -
Acknowledgement - - - - - - - - -
Table of contents - - - - - - - - -
Abstract - - - - - - - - - -

CHAPTER ONE
INTRODUCTION
1.1 Background of SIWES- - - - - - - -
1.1.2 Meaning of SIWES - - - - - - - -
1.1.3 Aims and Objectives of SIWES - - - - - -
1.1.4 Contribution of the scheme - - - - - - -
1.2 Profile of the organisation - - - - - -
1.2.1 Organisational chart - - - - - - - -

CHAPTER TWO
THE GEOLOGY OF JOS PLATEAU
2.1 Physical description - - - - - - - -
2.2 Geography - - - - - - - - -
2.2.1 Climate- - - - - - - - - -
2.3 History - - - - - - - - - -
2.4 Geology of the Jos-Plateau - - - - - - -
 CHAPTER THREE
PRACTICAL EXPERIENCE GAINED
3.1 Preliminary survey siting - - - - - -
3.2 Geophysical survey - - - - - - -
3.3 Geophysical survey equipment/instrument - - - - -
3.4 Survey methods use for water exploration - - - - -
3.5 Basic principles and theory of electrical resistivity method - - -
3.6 Factors influencing electrical resistivity value –
3.7 Electrode configuration - - - - - - -
3.8 Field data processing and interpretation - - - - -
3.8.1 Data interpretation ADMT - - - - - - -
3.8.2 Data interpretation in VES - - - - - - -
3.8.3 Field curves - - - -
3.9 Importance of data interpretation - - - - - -
3.10 Borehole drilling - - - - - - -
3.12 Methods of drilling - - - - - - - -
3.13 Equipment used in borehole drilling - - - - - -
3.14 Well logging - - - - - - - - -
3.15 Well casing - - - - - - - - -
3.16 Gravel packing - - - - - - - -
3.17 Borehole development / rehabilitation - - - - -
3.18 Flushing by compressed air (air lifting) - - - - -
3.19 Importance of borehole - - - - - - - -
 CHAPTER FOUR
CASE STUDY
4.1 Hydro geophysical survey - - - - - - - -
4.2 Location and accessibility - - - - - - - -
4.3 Google map of site - - - - - - - -
4.4 Geology and hydrogeology - - - - - - - -
4.5 Equipment and instrumentation - - - - - - -
4.6 Procedure - - - - - - - - - -
4.7 Methodology - - - - - - - - - -
4.8 Result interpretation - - - - - - - - -
4.9 Drilling recommendation - - - - - - - -
4.10 Borehole drilling - - - - - - - - -
4.11 Location - - - - - - - - - -

CHAPTER FIVE
5.0 Conclusion - - - - - - - - - -
5.1 Achievements / skills / knowledge gained - - - - - -
5.2d Problems / challenges encountered - - - - - - -
5.3 Recommendation
 ABSTRACT
The S.I.W.E.S program is principally geared towards the orientation of the students to the
society, industrial, domestic demands and needs of their course of study. In the light of this
my six months student industrial work experience scheme with WAKDEE Mines Limited, Jos
was a very good platform for me to actually bridge the gap between theoretical knowledge
acquired in school and the practical work situation of an organization thus fulfilling the aim
and objectives of the scheme. The company also is involve in, environmental impact
assessment, drilling of borehole and mining. My stay with the company exposed me to
various practical knowledge, technical know-how, data interpretational skills and report
writing. Projects involving geophysical survey for groundwater resources development,
drilling of borehole and Installation are some of the projects executed by the company, of
which I was actively involved.
 CHAPTER ONE
INTRODUCTION
1.1 BACKGROUND OF SIWES
SIWES was established by Industrial Trust Fund in 1973 to solve the problem of lack of
adequate practical skills preparatory for employment in industry by Nigerian graduates
of tertiary institutions. The Nigerian University Commission (NUC) comes in later to
assist the ITF in coordinating the program. In 1985, due to the increasing number of
students in the country, the federal government through the Federal Ministry of
Environment took over the funding of the program. The Industrial Trust Fund
established in 1971 admits the nationwide climate of accelerated economic activities of
the early 1970s as manpower development agency of the Federal Government of
Nigeria, specifically to provide service and facilities to the economy. The Industrial Trust
Fund enabling NO, 47 of 8th October 1971 was therefore, one of the major leverages by
which the government hoped to transform the economy of the nation from its
pronominal department of foreign expertise to a state of self-reliance through the
training and development of Nigerian, that would be competent to perform the
specialized skills required to manage essential of the national economy.
1.2 MEANING OF SIWES
The Students Industrial Training Work Experience Scheme (SIWES) often referred to, as
Industrial Training (IT) is an important feature of all professional and technical programs in
most part of the world. Though it is practical under different names such as practical
experience, teaching practice, houseman-ship, depending on the type of institution its basic
aim remains the same. Industrial Training may be defined as the practical skill training
experience based on the process of learning which link the theoretical classroom with the
practical work in the industry as a workshop or laboratory. This is geared towards increasing
the efficiency, effectiveness and hence productivity of the country’s graduates within its
labour market. The Industrial Training is backed by the new policy on education; hence, it
has become a national scheme and regarded as the major promoter of technological
training and industrialization in the country.
1.1.3 AIMS AND OBJECTIVES OF SIWES
 To expose and prepare students in related courses for industrial working situations they
may likely come across after graduation.
 To expose students to methods in handling equipment/tools that may not be available in
educational institutions.
 To give students the opportunity to apply their knowledge appropriately so as to bridge
the gap between theory and practical experience.
 To strengthen the relationship between industry and educational institutions.
 To prepare students for a prosperous industrial working life career and possible job
opportunities.
 To expose instructors and lecturers to new development in the industrial sector.
1.1.4 CONTRIBUTION OF THE SCHEME
The scheme is making a tremendous impact in the economy and technological development
of the country especially on human resources development. An elaborated summary of
some of the Contribution of the scheme are as follow;
 It offers the students an opportunity to associate themselves with workers at various
levels in the industries.
 It has contributed to the improved quality of skilled man-power in Nigeria.
 It prepares the students so that they can fit into employments in the industries.
 It creates more relationship between institutions and industries.
 It assures the institution that the qualities of student produced by them are to standard
after going through the SIWES program as it forms part of the assessment of the award of
certificate and degree.

1.1 BRIEF HISTORY OF WAKDEE MINES LIMITED

Wakdee Mines Limited was incorporated under the Company and allied matters of

1990 with the Corporate Affairs Commission of Nigeria. Its registration number is RC

730632, with its operational head office in Jos, Plateau State. The Company also operates

satellite offices on project-to-project basis.

The technical staff is made up of Engineers, Hydro-geologists, Geologists, Technicians and

craftsmen. Having been involved in supervision and execution of projects across the

federation, the company offers services as general contractors, mining, production of

general goods and merchandise.

1.2 FUNCTIONS OF THE COMPANY

As contractors, Wakdee Mines Limited is fully involved in offering but

not limited to the following services;

- Building design and construction

- Borehole design and construction

- Erosion/flood control

- Environmental pollution and Impact Assessment

- Project management

- General consultancy as hydro-geological investigation including

geophysical studies for water, well drilling and development, flushing

and Pump test

- Imports and exports

- Agro-allied services.

1.3 SERVICES PROVIDED BY THE COMPANY.

- Consultancy

 Detailed exploration of mineral raw material deposits to establish

reserves

 Borehole flushing using drilling rigs and Compressors

 Drilling for industrial and domestic portable water supply

  Environmental impact assessment and pollution control.

- Geophysical services

 Location of water borehole drilling point using Vertical Electrical Sounding

(VES) and Resistivity Profiling (RP) methods

 Engineering foundation studies using VES method

 Borehole Rehabilitation and Reactivation

 Pump test

 Baseline survey for water supply project

 Environmental Impact Assessment (EIA)

 Feasibility studies for water supply projects

1.4 ORGANISATIONAL STRUCTURE OF WAKDEE MINES LIMITED

Managing director/CEO

Chief
Hydrogeologist/Engineer Director Operations

Geological services Engineering services Administration,finance

department department and supplies
department

Geophysical Machine
survey,Research and maintenance,drilling and
development divisions mining divisions
 CHAPTER TWO
GEOLOGY OF THE JOS-PLATEAU
2.1 PHYSICAL DESCRIPTION
The Jos Plateau is a Plateau located near the Center of Nigeria. The plateau state derived its
name from the Plateau which the state is found on and the state's capital is named, Jos. The
plateau is home to people of diverse cultures and languages. Its central area covers about
3,000 sq mi (8,000 sq km) and has an average elevation of 4,200 ft (1,280 m); the
surrounding high plains often exceed 3,200 ft. The adjoining highland area on the east is
occasionally designated the Bauchi Plateau.
2.2 GEOGRAPHY
Plateau State is located in the North Central Zone out of the six geopolitical zones of Nigeria.
With an area of 26,899 square kilometers, the state has an estimated population of about
three million people. It is located between latitude 8°24' N and 10°30' N and longitude 8°32'
E and 10°38' E. The state is named after the Jos Plateau, a mountainous area in the north of
the state with rock formations. Bare rocks are scattered across the grasslands, which cover
the plateau.[11] The altitude ranges from around 1,200 meters (3,900 ft) to a peak of 1,829
meters (6,001 ft) above sea level in the Sheres Hills range near Jos. Years of tin and
columbite mining have left the area strewn with deep gorges and lakes. Adjacent states
Bauchi State – to the North East Kaduna State – to the North West Nasarawa State – to the
South West Taraba State – to the South East
2.2.1 CLIMATE
Although situated in the tropical zone, the higher altitude gives the state a near-temperate
climate, with an average temperature between 13 and 22 °C. Harmattan winds because the
coldest weather between December and February, with the warmest temperatures usually
in the dry season months of March and April. The mean annual rainfall varies between
131.75 cm (52 in) in the southern part to 146 cm (57 in) on the plateau, with the highest
rainfall during the wet season in July and August. The cooler climate has led to a reduced
incidence of some tropical diseases such as malaria. The Jos Plateau is it the source of many
rivers in northern Nigeria, including the Kaduna River which drains the western slopes,
flowing southwest to join the Niger, the Gongola River which drains eastwards to join the
Benue and the Hadejia and Yobe rivers flow northeast into Lake Chad.
2.3 HISTORY
Plateau state is located in the central region of Nigeria was created in 1976 during the
military regime of General Murtala Rahmat Mohammed. The state was carved out of old
Benue-Plateau state with Jos as its capital. The state is home to over 3 million people,
consisting of various ethnic and linguistic groups, including the Berom, Afizere, Tarok, Jukun,
and many more. Before the creation of plateau, the area was a part of the Benue-Plateau
state protectorate and later the northern region of Nigeria. The region’s economy was
initially dominated by agriculture, mining, and Jos, the state capital, was known for its
beautiful scenery, temperate weather, and rich cultural heritage. It is known for its rich
cultural diversity, tourist attractions such as the shere hills, the kurra falls, and many others.
It has also been home to some significant political leaders in Nigeria, including Solomon Lar,
Joshua Dariye, and Jonah Jang amongst others. However, Plateau state has been plagued by
ethnic and religious conflicts since the early 2000s, resulting in several outbreaks of violence
that led to the loss of lives, property, and displacement of people in the affected
communities. In 2009, Plateau state was listed among the states that had been hit by book
haram attacks. Today, Plateau state remains important in Nigeria’s JOS political and
economic landscape.
2.4 GEOLOGY OF THE -PLATEAU
The Jos Plateau is an area of younger granite which was intruded through an area of older
granite rock, making up the surrounding states. These "younger" granites are about 160
million years old. They occur as Ring Complexes such as the Jos-Bukuru Complex, Sara Fier
Complex, Buji Complex and Jarawa Complex. This creates the unusual scenery of the Jos
Plateau. The younger granites contain tin which was mined since the beginning of the 20th
century, during and after the colonial period. There are numerous hillocks with gentle slopes
emerging from the ground like mushrooms scattered with huge boulders. Also, volcanic
activity 50 million years ago created numerous volcanoes and vast basaltic plateaus formed
from lava flows. The phases of volcanic activities involved in the formation of Plateau State
have made it one of the mineral rich states in the country. Tin is still mined and processed
on the plateau. Figure 1: The geologic map of Plateau State.
 CHAPTER THREE
PRATICAL EXPERIENCE GAINED
In the course of my student industrial work experience (SIWES), I was able to put into
practice all that I had theoretically learnt in school. I gained practical knowledge in hydro
geophysical survey and borehole drilling. This technical report covers a documentation of
my exposure and experience gained during the student Industrial Attachment (IA), in the
area of Hydro geophysical Survey using pool finder plus, ADMT-400SX-16D and Electrical
Resistivity technique (Allied Ohmega Resistivity Meter) practically employing the
schlumberger configuration (geometry, array), equipment and field procedures used in
carrying out geophysical investigation, interpretation of data procured, digitally using zohdy
or win resist software program. The drilling of borehole with respect to the geology of the
environment using air rotary drilling and mud drilling (fluid).
3.1 PRELIMINARY SURVEY SITING
A preliminary survey siting, often referred to simply as preliminary survey or site survey, is a
process conducted before the commencement of the geophysical survey. Its purpose is to
assess and gather important information about a potential geophysical survey. The survey
involves a comprehensive evaluation of the proposed sites physical characteristics, such as
topography, soil composition, the rocks, drainage patterns, and vegetation information
helps in understanding the site’s suitability for the intended project. A preliminary survey
siting, often referred to as a preliminary investigation or pre-survey, is an initial assessment
or data collection process conducted before a more comprehensive study or project begins.
It helps in collecting essential data and information about the subject or area of interest,
providing a foundation for the survey or decision-making. The following are the preliminary
survey siting steps we take on the field;
 Confirm name and location of settlement.
 We delineate the near surface geologic structures such as faults and fractured zones.
 Check for possible outcrops if noticeable and their relationship to ground water
occurrence.
 Check if the study area is it covered by Sedimentary or Basement
 Check the relief of the area (Low land or High Land).
 Check and ask questions about pre-existing boreholes and wells in the area to have an idea
of what to expect.
 Look out for sources of noise e.g., high tension wires and communication mass and avoid
them.
 Check and ask for possible sources of contamination e.g., soak away and make sure the
distance between the site and the source of contamination is at least 20-25m away.
 Check the location of the site and land nature (space or no space), help us to know the
type of survey to apply at the site, in order for the drilling rig to be position easily.
3.2 GEOPHYSICAL SURVEY
The application of the principles of physics to the study of the Earth subsurface is term
Geophysical Survey, it aimed at solving Ground water problem, in three general categories.
A geophysical survey is a method used to study the Earth's subsurface by measuring various
physical properties of the ground. This can include techniques like seismic surveys,
electromagnetic surveys, gravity surveys, and magnetic surveys. Geophysicists use these
surveys to gain insights into the composition, structure, and properties of the Earth's
subsurface, which is valuable for various applications such as mineral exploration,
environmental studies, and locating underground resources. The company I did my
industrial training at use geophysical survey for Environmental Impact Assessment, mineral
exploration and water exploration. During my attachment, I actively participated in using
the geophysical survey for water exploration. The aim of carrying out this survey is to: a.
Identifying the location of Ground water b. Determining the Quality of the Ground water. c.
Selection of sites most favorable to high yield of water, in areas known to be water bearing.
3.3 GEOPHYSICAL SURVEY EQUIPMENT/ INSTRUMENT
The company have in possession all the basic equipment required for carrying out
Geophysical Surveys. The equipment’s used for geo electrical resistivity Survey include the
following:

 Allied Ohmega Resistivity Meter

 ADMT-300HT2 and other accessory equipment’s like hammer, Global positioning system,
chisel, measuring tape, cables, calibrated ropes,
Plate 1: picture of an ADMT-300HT2:
 ADMT-series of three-dimensional imaging cavity detectors are the most advanced
professional grade geophysical detectors for 3-dimensional imaging in the industry. The
instrument responds to changes in the underground resistivity by measuring the strength of
the natural electromagnetic field. In other to analyze and judge the location, size, depth and
other related information of underground cavities.
ADVANTAGES OF ADMT
1. High precision: equipped with high performance processor to run a variety of
algorithms, the output is stable and accurate, ensuring the accuracy of the
instrument in various environments.
2. Automatic drawing: After the measurement is completed a 2D, 3D color map and
variety of curve graphs will be generated.
3. Depth adjustment: Each product has a variety of adjustable depths; the number of
channels can be set.
4. Multi-screen data sharing: Mobile phone, computer, remote terminal data sharing
only need to log in with the same account.
Plate 2: Picture of ADMT-300HT2.

OHMEGA RESISTIVITY METER:

This is the major equipment or instrument use in carrying out electrical resistivity
survey of an Area of interest, basically both sedimentary and Basement complex. It is
used to measure the resistivity of the subsurface at different depth as a controlled
current is passed into the Earth. It measures the electrical resistivity of subsurface
materials, which can provide valuable information about the composition and
characteristics of the Earth's subsurface. The basic principle behind a resistivity
 meter is to inject an electrical current into the ground through two electrodes and
measure the voltage difference between two other electrodes. By analyzing the
resistance of the subsurface to the flow of electrical current, geophysicists can create
resistivity profiles or images of the subsurface. This data is used for various
applications, such as locating groundwater, identifying mineral deposits, assessing
soil and rock properties, and detecting buried archaeological features or
environmental contaminants. They are a valuable tool in geophysical exploration and
subsurface characterization. During the course of my industrial training, we use the
Resistivity meter for ground water exploration. Plate 3: Picture of allied ohmega
resistivity meter.
GLOBAL POSITIONING SYSTEM (G.P.S):
This is a space base navigation system (device) used to provide information on the
longitudinal and latitudinal coordinates of the study Area as well as elevation of a
location and that of sounding stations (VES points).

REELS (Current and Potential Electrode Wire):

These are instrument winded with an electric wire which are used for connecting the
electrodes to the resistivity meter and serve as the conductor through which current
passes to the electrodes and down into the subsurface, in the cause of the geophysical
survey operation. Usually, two pairs of cables are used, a pair for current (c1 and c2) and
the other pair for potential (p1 and p2). Plate 4: Current and potential electrode wire.

CALIBRATED ROPES (meters-M): This is also a reel although in this case it is a rope that
has been calibrated in meters from 1.5 to 215m, used for spreading (identifying the
distance moved apart) while carrying out the geophysical survey. Plate 5; Picture of a
calibrated rope.

METALLIC ELECTRODE:
These are survey tools made of metals with a pointed and sharp edge bottom for easy
penetration into the earth and a nub at the top. The current wire is usually tied to the
nub; which is then driven into the ground in order to conduct electricity down to the
subsurface. The electrodes are placed strategically during geophysical survey, which also
depend on electrode configuration used. The schlumberger electrode configuration was
used during my period of training.
Plate 6: picture of electrodes.
HAMMER: This is a hand-held tool consisting of a solid heavy metal which is used in
driving the metallic Electrodes deep (few cm) into the ground (sub-surface) while
carrying out the geophysical investigation.
Plate 7: Picture of a hammer.
MEASURING TAPE: A round narrow band of woven fabric, which is used for linear
measurement, each tape rule is about 50cm long.it is also used in identifying distance
move apart during survey operation.
Plate 8: Picture of a measuring tape.
CHISEL: A chisel is a tool with a characteristically shaped cutting edge of blade on its end;
for carving or cutting a hard material such as wood, stone, or metal by hand, struck with
a mallet, or mechanical power. In the field we use it for making holes when the ground is
strong before driving in the electrodes.
Plate 9: Picture of a chisel.

3.4 SURVEY METHODS USE FOR WATER EXPLORATION

The first stage of this the preliminary survey siting and the second stage the geophysical
survey which comprises of Horizontal Resistivity profiling (HRP) and vertical electrical
sounding (VES).
HORIZONTAL RESISTIVITY PROFILIG: This is achieved using a water detector called the
dowsing stick and ADMT-300HT2 configuration. The point is selected for successive
readings with fixed inter-electrode sounding. The inter-electrode spacing is set to be

10meters with station distance of 1m apart. The geometric factor is

given as k=2 a, a=k R where a is the inter-electrode spacing.
Plate 10: Picture of me using the A DMT.

VERTICAL ELECTRICAL SOUNDING:

Electric current is passed through the ground by means of two electrodes, and the potential
difference is measured across the electrode, in this way the subsurface resistivity is
measured using Ohm’s Law, and the resistance value is multiply by Geometric Factor (K) in
order to calculate the apparent resistivity (Schlumberger Array).The current flows within the
Earth and this in turn affect the distribution of electrical potential, the degree to which the
potential at the surface is affected, depends upon size, location and conductivity of the
material within the ground, it is therefore possible to obtain information about the sub-
surface. In homogeneous subsurface, this is the true ground resistivity, but usually it
represents a weighted average of the resistivity of all the formations through which the
current passes. It is the variation of this apparent Resistivity with change in electrode
spacing, and positions that gives information about the variation in sub-surface layering.
Whereas the wider the electrode spacing (AB) the deeper the depth of investigation (the
values of the Apparent resistivity).
Plate 11: VES showing the Schlumberger Array.
3.5 BASIC PRINCIPLES AND THEORY OF ELECTRICAL RESISTIVITY METHOD
Basically, the electrical resistivity method is conducted to measure and map the resistivity of
subsurface materials. It is also referred to as the survey carried out to present the image of
electrical properties of the subsurface by passing an electrical current along many different
paths and measuring the associated voltage. Electrical resistivity method is based on the
response between the earth and the flow of electrical current. It is sensitive to variations in
the electrical resistivity of the subsurface measured in Ohm meters. Resistivity
measurement are conducted by inducing or passing an electric current (using D.C or low
frequency A.C current) into the earth through or via two current (C1 and C2, source)
electrodes and measuring the resulting voltage at two potential electrodes (P1 and P2,
receivers). The apparent resistivity (pa) value can be calculated based on the current (I) and
voltage (V) .pa = k V / I Where K, represents the geometric factor that depends on the
arrangement of the four electrodes used. Imaging depth of electrical resistivity method is
dependent on the spacing between electrodes. Greater depth is achieved by increasing the
electrode spacing. The total length of electrode array also plays an important role in
resulting greater imaging depth. The overall subsurface resistivity also affects the imaging
depth with highly resistive ground tending to decrease the depth after inversion. The
resistivity values of groundwater vary in range from 10 to 100 ohm-m depending on the
concentration of dissolved salts contain as refer in Table 5. However, the overlap value
resistivity of different classes of waters is Dependent on several factors such as porosity,
degree of water saturation and concentration of dissolved salts.
Table 1: Resistivity values of some types of waters.

Type of water Resistivity (ohm-m)

Precipitation 30 – 1000
Surface water in area of igneous rock 30 – 500
Surface water in area of sedimentary rock 10 –100
Groundwater in area of igneous rock 30 – 150
Groundwater in area of sedimentary rock >1
Sea water 0.2
Freshwater 10-100
Drinking water (max. Sadly content 0.25%) >1.8

3.6 FACTORS INFLUENCING ELECTRICAL RESISTIVITY VALUE

Electrical resistivity is based on the principle that the earth material is being tested and acts
as a resistor in the circuit. After electrical current is induced into the ground, the ability of a
material to resist current were measured. Several of earth materials could be distinguished
by using this application since several of earth materials exhibit characteristics of resistivity
value. There were several factors that affected resistivity values of earth materials. The
ground resistivity value is influenced by various factors such as density, moisture content,
void ratio, grain size fraction and porosity. Electrical resistivity method capable in imaging
changes of apparent resistivity with depth locally and to detect the water saturated clay,
which is identified as lower resistivity zone. This application has theoretically stated that
water content in subsurface materials has a close correlation with the electrical
conductivity. Thus, the resistivity value will change or remain constant according to water
content in the materials. Degree of fractures is the common factors that influence resistivity
values. The fractures are commonly filled with groundwater. The greater the fractures the
lower the resistivity value of the rock layer. The statement could be understood, example by
resistivity of granite that varies within 5,000 ohm-m for wet condition to 10,000 ohmm in
dry condition. Resistivity value of these rocks will be low to moderate, which from few ohm-
m to less of hundred ohm-m when saturated with water. Soils that are located above water
table are much drier and have a higher resistivity value of several hundreds to thousand
ohm-m. While, soils below the water table generally gives resistivity value of less than 100
ohm-m. Other factors such as density, porosity, pore size and shape of the aquifer, quality
of water encountered in the aquifer and temperature of subsurface environment also
influence the resistivity value. The tables below show an approximate resistivity range of
some rock types;
Table 2: Approximate electrical resistivity ranges of some rock types.

ROCK TYPE RESISTIVITY IN Ohm/meters

Clay and marl 1-100
Loam 8-80
Top soil 80-120
Clayey soil 100-180
 Sandy soil 180-1800
Loose sand 1000-100000
Sandstone 20-10000
Basalt 20-1000
Crystalline rocks 1000-?

3.7 ELECTRODE CONFIGURATION

In electrical resistivity survey, high resolution, reliable and good imaging are dependent on
the choices of electrode configuration or normally known as array. Several studies have
been conducted regarding the performance of various array. In data acquisition, there are
many types of arrays to be used. The array configuration has a substantial influence on the
resolution, sensitivity and depth of investigation. Each of the array has its own specific
advantages and limitations. In choosing appropriate array several factors are considered
such as depth of object, type of heterogeneity to be mapped, vertical and horizontal
changes of the subsurface and signal strength. However, the objective of the survey is the
main factor to be considered. Emphasizes that on certain cases the use of various
configuration can improve the different reading characteristics of the subsoil and lead to a
better interpretation. The different types of electrode configurations (array/geometry)
applied in the acquisition of data while carrying out the Electrical Resistivity method of
geophysical investigation is the Schlumberger array others are (Werner array, Dipole
Dipole). However, the schlumberger electrode configuration was the most employed at
WAKDEE Mines Limited in obtaining the Vertical Electrical Sounding (VES) of the sub-
surface. A simple schematic arrangement of the Schlumberger layout is as shown below
Figure 2: A Sketch of Schlumberger array

Where; M & N= Potential Electrodes

A & B= Current Electrodes
S = Distance between Current Electrodes
a = Distance between Potential Electrodes
V = Voltage (Volts, V),
I = Current (Am)
TYPES OF ELECTRODE CONFIGURATIONS IN ELECTRICAL RESISTIVITY SURVEY
The different types of electrode configurations (array/geometry) applied in the acquisition
of data while carrying out the Electrical Resistivity method of geophysical investigation in
which data obtained in the field Schlumberger are interpreted are explained below

SCHLUMBERGER array: This is a type of electrode configuration in which the current and
potential pairs of electrodes have common mid-point but the distances between adjacent
electrodes differs. Two potential electrodes are installed at the center of the electrode array
with small separation typically less than one fifth of the spacing between the current
electrodes. In making depth sounding, the current electrodes (source) are moved in steps,
but the inner electrodes (receivers) are not moved unless the voltage observed between
them become too small to measure. It has the advantage(s) of detecting deep structures
and water bearing horizons. This array is most widely used for groundwater exploration.
Figure 3: Schlumberger array
ARRAY METHOD
WAKDEE Mines Limited uses the latest array method, the Schlumberger array. Two of these
arrays exist, that is the symmetrical and asymmetrical electrode configuration as best
applicable to the field condition. The symmetrical electrode configuration is used when the
availability of enough space permits the simultaneous spreading of electrodes in opposite
direction about the center of symmetry and vice-visa respectively. However, the
asymmetrical electrode configuration was the most employed during my industrial training.
3.8 FIELD DATA PROCESSING AND INTERPRETATION
3.8.1 DATA INTERPRETATION ADMT
The observed field data is converted to apparent resistivity values by inbuilt computer
algorithm of ADMT-300HT2. The Isoline graph for this profile was obtained by plotting the
data digitally on the ADMT-300HT2. A preliminary interpretation was carried out using color
matching involving different colors and the appropriate fracture systems with depth. The
layer model thus obtained served as basis for inferences and recommendationns.
Figure 6: Image
of the ADMT data
3.8.2 DATA INTERPRETATION IN (V.E.S)

Resistivity’s V.E.S. data are interpreted by plotting apparent resistivity values against AB/2
on a Log- Log graph sheet and the Data can be interpreted quantitatively; the plotting of this
graph can also be done using a software called zohdy and this was what we use during the
course of my industrial training. Example of curve obtained from zohdy Software, used in
the interpretation of field data obtained from ALLIED OMEGA METER Resistivity meter is
shown below
DEPTH (M) RESISTIVITY (Ohm-m)
0.85 711.64
1.24 517.25
1.82 373.45
2.68 171.19
3.93 174.74
5.77 337.50
8.46 510.88
12.42 637.72
18.23 952.84
26.76 1981.05
39.28 5107.33
57.66 14978.30
999999.00. 51929.95
 Figure 7: Typical VES curves obtained from zohdy
software
The data was obtained using the Allied Omega Resistivity Meter. This is due to the precision
of this instrument as compare to others and it is water resistance. It is one of the costliest
survey instruments. The data was interpreted using computer software. The software used
was the zohdy programme. There are others software that can also be used such as the IXD
software, IPI3, win resist. The shape of a V.E.S curve depends on the number of layers the
subsurface, the thickness of each layer, and the ratio of the resistivity of the layers. The
number of inflection points on V.E.S curves gives some idea of number of layers in the
subsurface geological section of the area of survey.
TABLE 3: EXAMPLE OF THE ABOVE GRAPH, FIELD DATA INTERPRETATION

Layer Depth (m) Resistivity Inferred Lithostrata Remark

(ohmm)
1 1.04-3.30 244.27-385.18 Top Soil Dry
2 3.30-10.44 385.18-64502 Fairly Weathered
Granite Moderate Yield
3 15.34-71.19 129.77-873.44 Faily Possibly
weathered/fractured Aquiferous
Granite
4 71.19-??? 810.93 Fairly Weathered Moderate Yield
Granite
3.8.3 FIELD CURVES:
There are basically four (4) main types of curves namely K-curve, H-curve, A-curve and Q-
curve, with their combination. The shape of a curve depends on the number of layers, the
sub-surface, the thickness of each layer, and the ratio of the resistivity of the layers, the
number of inflection points on V.E.S curves gives some idea of number of layers in the sub-
surface geological section of the area of survey. K-curve: it is indicative of fracture, in a
crystalline environment during ground water exploration, knowing the depth is required
dividing the electrode spacing by 3 at that point, it is a good curve in crystalline environment
but when produced in a sedimentary environment the depth would determine if it’s an
aquifer or not. H-curve: As S2 resistivity drops and at S3 it increased indicating a very good
curve in a crystalline environment base on its depth, in terms of ground water exploration
while it is good for sedimentary environment too because it shows deep aquifers A-curve:
Resistivity increases in A-curve with depth during water exploration; it is a bad curve in a
crystalline environment, but a very good curve in a sedimentary environment. Q- curve:
Resistivity reduces with depth on Q curve during ground water exploration. It is very good in
a crystalline environment especially in Jos water table but bad for sedimentary
environment.
3.9 IMPORTANCE OF DATA INTERPRETATION
a. Data interpretation aids in the reconstruction of the geology of the subsurface
b. It makes drilling accurate and save cost of unnecessary expenses
c. Data interpretation report is useful for future reference during maintenance of borehole.
d. Data interpretation helps the client to estimate the total cost of the borehole process
3.10
BOREHOLE DRILLING
Drilling can be defined as a cutting process which bores a hole of circular cross-section
vertically into the ground (borehole) to penetrate the aquifer within the saturated zone.
Underground water is stored in cracks (fractures) within rocks (naturally occurring solid
aggregates of two or more minerals) using a machine called the drilling Rig. However, this
borehole has to properly designed, professionally constructed and carefully drilled.
Generally, the rate of rock drilling is directly proportional to the rock drill ability that is, the
rock drill ability is a function of the rock strength. Basement rocks are hard, compact and
mostly crystalline, hence exhibits high drill ability. It should be noted that not all fractures
encountered when hammering is water bearing since some fractures are dried in most
instance the more the number of waters bearing fractures encountered, the better is the
water yield of the well. The rate of penetration decreases as soon as the rock encounter is a
fresh basement and the cutting also starts coming out in a dry powdered form. At this stage
the possibility of encountering any more fracture is very slim; hence the drilling can be
terminated. Drilling operations depends on the geologic setting and purpose of the well. The
drilling operation learnt was for the purpose of water well. Once a site has been explored
and marked as a suitable site for borehole drilling, the proper drilling method must be
chosen on the following basis; Purpose of the well Depth and diameter Geologic setting or
hydro geologic environment Quantity of water required and Economic factors.
3.12 METHODS OF DRILLING
The various drilling systems (methods) used for water boreholes includes; Hand-Auger
drilling, Sludging, Jetting, Rotary mud drilling, Rotary and air percussion drilling. However,
only two drilling method is being used at WAKDEE Mines Limited and it is the air Rotary
drilling and mud drilling fluid system. Air rotary drilling: In this method of drilling, air alone
lifts the cuttings from the borehole; a large compressor provides air that is piped to the
swivel hose connected to the top of the Kelly or drill pipe. Air forced down the drill pipe
escapes through small openings at the bottom of the drill bit, there by lifting the cuttings
and cooling the bit, cuttings are blown out the top of the hole and collected at the surface
around the borehole for every stem used and used to construct the lithology. Air rotary
drilling can be done only in semi consolidated or consolidated formation, with rig equipped
with air compressor. The path for fluid circulation during air rotary drilling is the same for
mud rotary drilling. Air travels from compressor to the Kelly or swivel down the drill pipe
through nozzles in the bit and exit along the borehole walls outside the drill pipe. During
drilling the clay cutter is screwed into the drilling rod, which is screwed to the swivel head.
The work of the clay cutter is to open the loose surface of the earth (Over burden). This is
achieved by the rotary movement of the clay cutter. On reaching the basement, (rocks of
the basement complex) the clay cutter is replaced with the hammer bit, a temporary casing
of length which is equal to the depth of the over burden is inserted into the borehole to
prevent the hole from caving. After drilling to the recommended depth by screwing more
drilling rods together and getting to the aquiferous region, the drilling rods are pulled out
one after the other and a permanent casing is inserted into the borehole.
3.13 EQUIPMENTS USED FOR BOREHOLE DRILLING

Drilling equipment is constantly developed to suit modern processes of drilling (practices),

the following equipment were utilized for different purposes during the training.
DRILLING RIG: This is the main drilling equipment usually with a mounted or detached
compressor and support truck that carries other accessories; generator, air hoses, water
hoses, temporary casing, rod stem, tank amongst others. The rig is the most important
equipment in drilling and thus highly protected and maintained.
Plate 12: Drilling rig

DRILLING RIG PARTS AND FUNCTIONS;

➢ ROTARY HEAD OR ROTOR HEAD: For the rotary movement of the machine that drives
the drilling rods.
➢ HYDRAULIC SYSTEM: Helps the mast to stand during drilling activity.
➢ MAST: The pole which the swivel sub and other equipment such as strings and is
always standing erect when drilling is going on.
➢ SWIVEL SUB: The part which connect drilling rod to the rotor head.
➢ PRIME MOVER: The engine section with gears, where power is generated.
➢ HYDRAULIC TANK: Controls and provides force for the machine hydraulic system.
➢ HYDRAULIC JACK: For machine suspension on the surface level.
➢ LEVER: To confirm the position of rig and ascertain balance.
➢ MUD PUMP: For the circulation of mud during rotary mud drilling.
➢HOISTING EQUIPMENT: Used to lift whatever tool may go into or come out of the
well.
2. DRILLING STEM/RODS: These are heavy steel pipes fixed to the drilling bit which helps
in determining the length of the borehole and the transfer of compressed air or mud
solution to the borehole. Plate 13: drilling rods.
3. HAMMER BIT: This special equipment has a barrel assembly for breaking rock
formation in basement areas or highly consolidated sedimentary areas.

plate 14: Hammer bits.

4. ROLLER BIT (CLAY CUTTER): This is used for clearing/drilling through clay, silt
(combination of clay and sand) and mica layers or formation.
5. PERMANENT CASING (SCREEN AND BLIND CASING): These are plastic pipes which are
inserted in the borehole so as to enable the ascension of water (capillary effect) or other
fluid and also prevent the walls of the borehole from collapsing.
6. TEMPORARY CASING: This is a metallic pipe used for the prevention of loose topmost
materials from falling in the borehole or well.
7. DRILLING RODS DISENGAGER: This tool is used in loosening and supporting of drill
rods while disengaging them at the end of a drilling exercise.
8. CHAIN TORQUE: Used for tightening or loosening drilling rods and temporary casing
9. FLUSING PIPES: Used when flushing borehole.
10. PIPE RANGE: Used for tightening and loosening of pipes and hoses.
11. TOOLS BOX AND CABINS: For safe keeping and storing of boring, packing and
heating tools that are simple and portable such as screw drivers, spanners, saws,
hammers etc.
3. 14 WELL LOGGING.
• Litho-log is a drilling log which is a written record of the geological formations (soil
layers) drilled according to depth. Soil samples should be taken at regular depth (e.g
every meter but we usually take our sample after each stem of the rod) and described
during the drilling process. The soil description is then recorded in the form of a drilling
log. The drilling log will help us to determine:
• The right aquifer for installation of the well-screen.
• Depth and length of the well-screen.
• Depth and thickness of the gravel pack. While drilling, either Air Drilling or Mud Drilling
it is important to keep records and Log of the drilling operation for decision on casing
installation, management of drilling problem that may arise and management of
subsequent drilling and in interpretation of this.
Plate 15: Well logs from the field. 3.15
WELL CASING The next phase in the process of borehole construction is well or hole
completion. In water boreholes, well completion may be reviewed as the techniques of
making and retaining an efficient connection with a desirable aquifer or aquifers while
effectively shutting off undesirable horizons in sub surface. This objective is acquired by
the use of casings, screens and seals. Installation of permanent casing Immediately after
completion of drilling to the required depth, casing is installed into the well, there are
two type of polyvinyl chloride (PVC) casing, the screen casing and blind casing, The
screen should be installed in the water bearing formation and should have sufficient
open area (determined by slot and length) to allow the water to flow freely into the well,
It also serves as filter to prevent large particle of sand entering the borehole.
BLIND CASING: These are pipes of different dimensions and made of different materials,
such as wrought iron, alloyed and unalloyed steel, ingot iron and polyvinyl chloride (PVC)
pipes (shallow and small diameter holes), However the PVC pipes were used during the
training.
FUNCTIONS
➢Provide lining to maintain an open hole from ground surface to the aquifer
➢ Seals out surface water and any undesirable ground water,
➢ Provides structural support against caving material
SCREEN CASING: These are slotted pipes of different slot sizes made up of polyvinyl
chloride (PVC), it is the same as that of the blind casing, only that it is perforated to
allow inflow of fluid
FUNCTIONS
➢stabilizes the walls of the holes (adjacent to aquifer)
➢ Prevent sands from getting into the well
➢ Allows maximum quantity of water in to the well with minimum hydraulic resistance
3.16
GRAVEL PACKING
Gravel packing involves placing of envelope around the screen casing and part of the
blind casing, the functions of the gravel pack are:
• To stabilize the aquifer, and prevent sudden collapse (Caving of the Borehole) of the
formation, which can damage the screen. Hard rock, (e.g. sand stone and basement
complex) materials usually provides little or no lateral support for the casings and
screen.
• Formation does readily slump during development in contrast to unconsolidated
sediments.
• The gravel pack supports the boreholes wall and the blind casing/screen casing.
• It permits the use of large screen slot, which provides large open area.
• It prevents the entrance of finer formation materials into the well thereby reducing
possible sand pumping.
• It provides an annular zone of permeability which increases by yield of the well.
• It helps in protecting the veins or fracture from blocking. In general terms, gravel
packing is the placement of 80mm-12mm thick pack of carefully selected coarse sand or
Gravels in borehole annular space. It is important for the thickness to fall within this
limit, if the thickness is smaller than 80mm bridging of gravels will occur during
placement. Gravel materials should have high percentage of Quartz but low in
feldspathic material, because they are resistant to Abrasion than mica and they should
be clean and well rounded.

3.17 BOREHOLE DEVELOPMENT/REHABILITATION

Well development is the final phase of operation in water borehole construction. The
objective of well development is to break-up or dissolve the mud cake and flush out the
fines and drilling fluids in the screen area. In this manner, near well permeability is
increased and water can then flow from the formation into well without turbulence for
head loss.
3.18 BY COMPRESSED AIR (FLUSHING AIR LIFTING)
The most important aspect of this process worth looking at closely is air lifting
development using compressors, the benefit of this method offers as follows.
• The borehole bottom can be suction cleaned by this method - No pump is damaged as
a result of pumping sand.
• Fine cuttings are brought from the formation into the borehole by the surging action of
the water column. The intensity of agitation can be increased or decreased
3.19 IMPORTANCE OF BOREHOLE
a. Borehole provides ground water which is a very important resource known to occur
widely than surface water.
b. Borehole drilling provides lithology used to reconstruct the geology of the subsurface.
c. It helps in the analysis of lithology by collecting samples of drill cutting at every
lowering of each drill stem.
d. Areas covered by basement and other crystalline rocks ground water would be only
source of water when surface water is either seasonal or non-existent.
INSTALLATION OF SUBMERSIBLE PUMP
The installation of electrical submersible pump of different power rating into the well
becomes so dependent on the yield of the boreholes. The pump is installed by attaching
riser pipe to the socket like threaded end of the pump and also aided by marine rope.
This is connected to an electrical power supply source through flexible cable fixed to its
side which in turn is activated by a suitable rate electrical motor which is a very sensitive
conductor designed by stable motor and has the ability to trip off at the slightest voltage
fluctuation. The size and type of pump to use are dependent on factors such as:
Pumping capacity, Well depth and diameter, Depth and variability of pumping level,
Duration of pumping, Type of power available and cost.
3.14 IMPORTANCE OF PUMP TESTING AND INSTALLATION
Ø Pump testing is a good time to collect water quality samples to assess the chemical,
physical and bacterial properties of the water.
Ø Gives information on water quality and its variability with time.
Ø Aids in the determination of the hydraulic properties of the aquifer.
Ø Helps to determine how much groundwater can be extracted from a well based on
longterm yield, and well efficiency. Ø Gives information on the spatial effects of pumping
on the aquifer.
PROBLEMS ASSOCIATED WITH BOREHOLE DRILLING

They include; casing jamming, hole deviation, drill bit jamming, hole caving/collapsing,
pipe sticking, loss of circulation, pipe failures, borehole instability, mud contamination,
formation damage, hole cleaning etc. Few of these problems will be briefly explained
below; Casing Jamming: Casing (Screen Jamming) During Installation: When the
borehole is not properly flushed or where the borehole cave without the knowledge of
the operator and the presence of drill cuttings or clay settles at the bottom of the hole, it
becomes very difficult to install the full length of casing desired, as there will be jamming
and the casing might refuse to enter fully. When this problem is encountered the best
thing to do is to pull out the casing carefully, then back flush the hole, a clay cutter bit
can be used to increase the diameter also, just to allow for easy entrance of the casing.
 CHAPTER 4
CASE STUDY
4.1 HYDROGEOPHYSICAL SURVEY
This is one of the several geophysical survey I was opportune to have been actively
involved in.
4.2 LOCATION AND ACCESSIBILITY
The study area is located in SHINKO JUNCTION, Opp.Florence nightingales nursing school
Rayfield,Jos SouthL.G.A., Plateau State on latitude N90 53’ 08’’ and Longitude E80 57’
43’’. The access roads are always accessible.
4.4 GEOLOGY AND HYDROGEOLOGY
Shinko junction opp, Florence nightingales nursing school rayfield, is underlain by biotite
granites which are Jurassic in age and the Basement complex rocks. The presence of
groundwater in any rock presupposes the satisfaction of two factors: adequate porosity
and adequate permeability. On account of their crystalline nature, the metamorphic and
igneous rocks of the Basement complex satisfy neither of these requirements.
4.5 EQUIPMENT AND INSTRUMENTATION
The following are some of the equipment / instruments used during the course of this
survey: Tape, hammer, sensor, ADMT, resistivity meter, current and potential
electrodes, calibrated rope and pool finder.
4.6 PROCEDURE
 We start by carrying out the preliminary survey check for outcrops if available, and the
trend of fractures and strikes on the outcrop, check the relief of the site and check for
outcrops.
 We ask questions about the existing borehole and wells.

 Check for possible sources of contamination and avoid them.

 Check possible sources of noise and avoid them.

 It was a church compound so we had space

4.7 METHODOLOGY
 We switched on the ADMT and set it to probe for water at the depth of 300 meters.

 We used it to probe the site and found four points of interest.

 We run the reverse of each point

 The point was marked

 We now used the tape to mark 10/18 points of fixed spacing of 1/2 meter apart

 Now connecting the ADMT to the sensor and using it to probe along the marked
points.
 The machine plots the frequency graph after the measurement.

 The line graph and profile were obtained after the survey.

 The same thing was repeated for the remaining points identified by the ADMT.

 We set up the resistivity meter using the slumberger array.

 As carry out the procedure one person is operating the equipment while the other
driving the electrode into the ground.
 We spread from 1.5 – 215 meters to get 71 meters as depth.

Figure 9: Profile 1 P
 Figu
re 10: Profile 2

4.8 RESULT INTERPRETATION

When interpreting the ADMT results we put two things into consideration. The first is
the color; from the chat you will see at the color purple we have the lowest resistivity
value and the orange with the highest resistivity value. Since we are exploring for water,
we watch out for low resistivity values. The second thing we watch out for is the
fractures (contour). I.e., places of plenty fracture.
For the resistivity meter after collecting the data from the field we use the zohdy
software to computer the data and come up with a graph. This was the graph we got.
The Geophysical sounding interpretation shows depth to the various geo-electric layers
as follows:
VES 1

Layer Depth (m) Resistivity (ohm-m) Inferred Lithostrata Remark

1 0.72-3.35 171.06 – 299.92 Topsoil Dry
2 4.92-15.55 393.09-457.33 Fairly Weathered Moderate yield
Granite
3 22.82-49.17 401.18-473.82 Fairly Weathered Moderate yield
Granite
4 49.17- ??? 314.10 Weathered/Fractured Possibly
Granite Aquiferous

Table 4
4.9 DRILLING RECOMMENDATION
Based on the field observation and the interpretation of the data obtained, borehole
drilling within the studied area is fairly feasible. The groundwater potential is expected
to be of MODERATE YIELD.
PROFILE 2, POINT 2 and 5 at a depth of 180M is the best within the studied area and
advised for a good yield.
4.10 BOREHOLE DRILING

During the course of my industrial training this was one among the many drillings I went
for.
4.11 LOCATION
The site was BHUNGA Mangu L.G.A, Plateau state on latitude N90 73’ 48’’ and Longitude
E80 87’ 93’’. The access roads are ACCESSIBLE.

S/NO DEPTH(M) DESCRIPTION REMARK

1 0-4.6 Lateritic, moist Top soil
2 4.6-9.2 Lateritic, very moist Overburden
3 9.2-13.8 Lateritic, very moist Overburden
4 13.8-18.4 Lateritic, very moist Overburden
5 18.4-23 Lateritic, very moist Overburden
6 23-27.6 Rock fragment and Weathered rock
water
7 27.6-32.2 Rock fragment and Weathered rock
more water
8 32.2-36.8 Quart’s fragment Fractured
and plenty water basement
9 36.8-41.4 Quart’s fragment Fractured
 and plenty water basement
10 41.4-46 Rock fragment and Fractured
water basement
11 46-55.2 Rock fragment, Fractured
Quarts and water basement

Table 5: Well log of borehole drilled.

The borehole was cased fully was plain and screen casing.
 CHAPTER 5
5.0 CONCLUSION
 Hydro geophysical survey is non-negotiable in the exploration and exploitation of
groundwater resource. The negligence of this practice has led to most failed boreholes
in recent time the fractures are either dry or wet.
 Professionals should pay attention to the preliminary stages of exploration to reduce
the number of abortive boreholes.
5.1 ACHIEVEMENTS/ SKILLS/KNOWLEDGE GAINED

My industrial training with WAKDEE Mines Limited has indeed exposed and
broadened my knowledge to the practical application of geophysical method,
precisely the electrical resistivity technique of groundwater investigation. I was
privileged to work in both the geophysics and drilling section and can now effectively
carry out survey to standard for example to detect sources of field errors and
proffering solutions, process a report, interpret a report using the zohdy and win
resist software program which was very vital for geophysical data analysis and
interpretation and also give recommendation on drilling and carry out drilling. I also
learnt how to develop a borehole.
5.2 PROBLEMS / CHALLENGES ENCOUNTERED

1. Lack of proper access road to some localities or communities. On several occasions

our Drilling Rig was trapped on our way to executing projects due to the nature of
the bad
2. During the rainy season, there were no much projects to execute so our learning
limited too few occasions when the company was awarded drilling contracts.
3. Some terrains are difficult to find water, such as HWOLSHE area of Jos North, so
proper survey needs to be carried out by experienced hydrogeologists before
drilling.
4. Even after proper survey, not all boreholes yielded as much water as indicated by
the survey report, thus not all subsurface fractures are aquiferous.
5. Surveys may not always give the accurate depth to which a borehole should be
drilled, thus clients should be patient with drillers even where they may have to drill
deeper than the anticipated depth. Surveyors should also make this clear to their
clients before embarking on a drilling project.
5.3 RECOMMENDATION

Students should be encouraged to go for internship with this geological firms and
not just wait for the SIWES so that by they will have more exposure and by the time
they go for their industrial training they just be building on the practical knowledge
the already have.

REFERENCES

-the new penguin dictionary of geology 2nd edition London.

-united states environmental protection agency, Environmental geo-physics;
resistivity method
-wakdee mines limited [2025]. company profile rayfield jos.

Photos of me at the site