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The Hydro geology of Offa, Southwestern Nigeria and its impact on the Groundwater quality.
CONTENTS PAGE

Acknowledgement                                                                                                   iv List of Abbreviations                                                                                               v List of Figures                                                                                                     vi List of Tables                                                                                                      ix Abstract                                                                                                            1

Chapter 1.0	Introduction	                                                                                   3 1.1	Influence of hydrothermal alteration on groundwater. 7 1.2	Common threats to the aquifer systems. 8 1.3	Aims and Objectives. 8 1.4	Background statement. 9

Chapter 2.0	Basement Complex of Nigeria. 10 2.1	Location of the study area (Offa). 12 2.2	Geology of the study area. 15 2.3	Hydro geology of Offa. 16 2.4	Vegetation and Climate. 17 2.5	Drainage and Topography. 17 2.6	Lithologic description of the rock samples in the study area. 19 2.7	Petrography description of the rock sample. 20

Chapter 3.0	Method of investigation. 22             3.1	Measurement of Hand-dug well. 25             3.2	Method of determination of groundwater flow-net direction. 26             3.3	Methods of hydro chemical assessment. 28 Chapter 4.0 4.1	Results of the Chemical analysis of Offa samples. 29             4.2	Presentation and interpretation of results. 30             4.3	Interpretation/contour map presentation and interpretation. 30             4.3(i)	Sodium ion. 31             4.3(ii)	Potassium ion. 34             4.3(iii)	Calcium ion. 36             4.3(iv)	Chloride ion. 38             4.3(v)	Cations. 40             4.3(vi)	Sulphate ion. 41             4.3(vii)	Nitrate ion. 43             4.3(viii)	Phosphate ion. 45             4.3(ix)	Anions. 46             4.3(x)	Total Dissolved Solid (TDS). 48             4.3(xi)	Total alkalinity (TA). 50             4.3(xii)	Electronic conductivity (EC). 52             4.3(xiii)	Total hardness (TH). 54             4.3(xiv)	Lead (Pb). 56             4.3(xv)	Zinc (Zn). 57             4.3(xvi)	Heavy metals. 58             4.3(xvii)	pH concentration. 60             4.3(xviii)	Temperature. 62             4.4	Hydro chemical facies. 64

Chapter 5.0	Discussion. 66 5.1	Comparison of Offa result with some other urban groundwater Pollution case histories                                                                       66 5.2	Conclusion. 72

Ways to expand and improve this study                                                                      74

References                                                                                                 75

ACKNOWLEDGEMENTS

I appreciate every members of my family who have all been a huge support to me since I began my degree. I am unable to thank every individual who has supported me during both the fieldwork and period of writing this dissertation, you are the best family in the world and thank you so much for the patience, love, advice, support and inspiration, and may God bless u all.

This dissertation would not have been accomplished, without the great assistance, advice and patient of Dr Andrew Johnson and Prof.Aradhana Mehra, Oliver Tomlinson, my tutors and mentors for their unwavering support and guidance towards the success of this study. Thank you very much for the precious time you have dedicated to me, for the success of this study. I appreciate my friends, most especially Bolaji Johnson, thanks so much for your encouragement and support. I am sure other friends know who they are and I hope they truly know how much their support has meant.

Lastly, my endless appreciation goes to my heart rob (Olaolu), even though I may not have shown it at times, but I was and always will be grateful for your endurance, help, prayer and support over the past years.

LIST OF ABBREVIATIONS

WHO		World Health Organisation FEPA		Federal Environmental Protection Agency Mg/L		Milligrams per litre GIS		Geographical Information System. TL1-19		Well sample locations in Offa area. SE		Surface Elevation. WD		Water Depth. WT		Water Table TDS		Total Dissolved Solid. EC		Electrical Conductivity. TA		Total Alkalinity. TH		Total Hardness. PO4−		Phosphate. SO42−		Sulphate. NO3−		Nitrate. ca2+		Calcium. Na+		Sodium. K+		Potassium. Cl−		Chloride. Pb		Lead. Zn		Zinc. Temp. Temperature. COD		Chemical Oxygen Demand. CHS		Chlorinated Hydrocarbon Solvent Org. Organic determinant. Nd		No data.

LIST OF FIGURES

Figure 1	Diagram showing saturated and unsaturated zones in ground- Water. Figure 2	Diagram showing types aquifer in relation to the groundwater. Figure 3	The map of Nigeria showing basement complex. Figure 4	Map of Nigeria showing region of the study area. Figure 5	Picture of opened hand -dug well in Offa Township. Figure 6	Picture of well with concrete rim and covered metal plate. Figure 7	Picture of Municipal dumpsite in Offa. Figure 8	The map of Kwara State showing the Offa Township. Figure 9	The Map of drainage pattern in Offa, Nigeria. Figure 10	The picture of the rock sample found at Akewusola’s compound. Figure 11	The diagram showing the thin section of fine medium grained Gneiss Found at Akewusola’s compound (TL15) in Offa. Figure 12	The GIS map of Offa showing the municipal dumpsite, Atan stream  and Agun stream. Figure 13a	Diagram showing groundwater flow-net direction. Figure 13b	Diagram showing groundwater flow-net direction. Figure 14a	Plot showing the concentration of Na2+  in the well water sample. Figure 14b	Interpolated G.I.S contour map of Na2+ concentration in the well Samples Figure 15a	Plot showing the concentration of K+  in the well water sample. Figure 15b	Interpolated G.I.S contour map of Phosphate concentration in                      the well samples. Figure 16a	Plot showing the concentration of Ca2+  in the well water samples. Figure 16b	Interpolated G.I.S contour map of Ca2+ concentration in the well Samples. Figure 17a	Plot showing the concentration of Cl- in the well water sample. Figure 17b	Interpolated G.I.S contour map of Cl- concentration in the well Samples. Figure 18	Plot showing concentration of Cations in the well sample. Figure 19a	Plot showing the concentration of SO42-  in the well water samples. Figure 19b	Interpolated G.I.S contour map of SO42- concentration in the well samples. Figure 20a	Plot showing the concentration of NO32-  in the well water sample. Figure 20b	Interpolated G.I.S contour map of Ca2+ concentration in the well Samples. Figure 21a	Plot showing the concentration of (PO43-). in the well water samples. Figure 21b	Interpolated G.I.S contour map of (PO42-) concentration in the well samples. Figure 22	Plot showing the concentration of Anions in the well water. Sample. (Chloride, Sulphate). Figure 23a   Plot showing the concentration of TDS in the well water sample. Figure 23b	Interpolated G.I.S contour map of TDS concentration in the well Samples Figure 24a	Plot showing the concentration of TA in the well water sample. Figure 24b	Interpolated G.I.S contour map of TA concentration in the well Samples. Figure 25a   Plot showing the concentration of EC   in the well water sample. Figure 25b	Interpolated G.I.S contour map of EC concentration in the well Sample. Figure 26a   Plot showing the concentration of  PO42-  in the well water sample. Figure 26b	Interpolated G.I.S contour map of T.H. concentration in the well Sample. Figure 27a	Plot showing the concentration of Pb in the well water sample. Figure 27b   Interpolated G.I.S contour map of Pb concentration in the well Sample. Figure 28a	Plot showing the concentration of Zn in the well water sample. Figure 28b	Interpolated G.I.S contour map of Zn conc. in the well samples. Figure 29	Plot showing the concentration of Toxic element in the well water sample. (Pb and Zinc). Figure 30	Plot showing the concentration of Heavy metal in the well water Sample (EC, TDS, TH, and TA). Figure 31a	Plot showing the concentration of pH in the well water samples Figure 31b	Interpolated G.I.S contour map of pH concentration in the well samples. Figure 32a	Plot showing the concentration of Temperature in the well water. Figure 32b	Interpolated G.I.S contour map of Temperature concentration in                        the well samples.

LIST OF TABLES

Table 1 	The table showing well locations and measurement. Table 2         Results of the Analysis of water samples from Offa groundwater. Table 3	Table showing W.H.O AND FEPA Recommendation Standard Values for Portable, water (W.H.O, 2008). Table 4	 Case history of some urban groundwater pollution (Adapted and modified from Yusuf, 2007).

ABSTRACT

Ground water assessment has been highly probed in recent time and in various places. This research work determined the ground water flow-net direction and, also examined and assessed the levels of some physical, chemical, biochemical, and Microbial water quality parameters in Offa area of South-western, Nigeria with a view to determine their suitability for human consumption. The result of this study is compared with the work of other academics from different part of the world.

The knowledge of the amount of natural recharge to an aquifer is compulsory in a ground water study. The groundwater potential in Offa area, improved with induced secondary permeability derived from fracture, joint and solution channels. The main controls of the occurrence and flow net rates of ground water are usually the porosity and permeability of the groundwater reservoir (Babara, 2001) and these two controls, are lacking in the Offa area, because the study area lies within the crystalline basement. The outcome of the study in Offa area shows that Agun and Atan streams recharge the ground water in the area. Moreover, most of the water requirement for Offa is obtained, from the surface and ground water supplies. The insufficient supply of pipe-borne water due to Increase in the population has forced majority of the people in the area to depend on the well water as source of portable water. The water samples collected in Offa were analysed in a Laboratory in Lagos, Nigeria using Atomic Absorption Spectrometer (Perkins imer 306) with wave length of 285.The values obtained are reported in Milligrams per litre (Mg/L). The results obtained from the laboratory, were presented and interpreted using Arc view software in GIS. This software was used to construct the interpolated maps of each parameter detected in the well water samples from the study location.

Furthermore, the results of the hydro chemical analysis of the water samples collected in the study location show that the samples closer to the source of pollution consist of toxic elements, cations, anions and heavy metals with higher concentration of Total dissolved solid (TDS). Apart from TDS, all other parameters conformed to W.H.O recommended standard, but water from most of the wells is not properly clean and pure enough for human consumption. Adequate treatment is required in some hand-dug wells in the study area, to avoid unexpected water-borne disease that, could lead to serious epidemic diseases. In addition, to combat the groundwater pollution in the study area, I recommended that wells in the study area and other places should be constructed beyond 300m from any identified source of pollution. Modern and standard solid waste disposal technique such as recycling should be implemented; and provision of modern incinerator is required in appropriate place in Offa area.

CHAPTER ONE

1.0   Introduction

Groundwater is water contained in Fractures, sediments and underground caverns .It occurs 40 times greater than the fresh water such as lakes or streams. There is also a small volume of groundwater at greater depth, formed as a result of the high pressure exerted by the overlying rocks, which extremely reduces the pores size. Groundwater flows very gradually between grains of sediments; the flow is slow enough to the extent that it forms laminar flow, while turbulent flow occurs mainly in fractured bedrock or underground Caverns. (Close, 1989)

The typical rates of groundwater flow is (15m/year) or 4cm/day(Hem, 1985).The main controls on the occurrence and the flow rates are the porosity which is defined as the % of void space in a reservoir that may be filled with water, this determines the quantity of fluid a rock or sediment can retain. The size and shape of the rock particles as well as compactness of their arrangement are the main factors, which affect the porosity. On the other hand, permeability of the ground water reservoir is the measurement of the ease of flow of fluids through a rock body. Permeability also measure, the rate with which water flows through pores in a rock unit .This often describes extent to which pores are interconnected. In addition, there are different porosity and permeability occurrences in different rocks, which explain the reason why water does not flow in all rocks in the ground in the same manner (Barbara, 2001) The rocks with low porosity often have low permeability since the pore size and the interconnectivity of its pores also have impact on the ability of the fluids to move through the rock.

The saturated zone is classified, as the ground below the water table while unsaturated is the ground above the water table, as shown in figure 1. Meanwhile the saturated zone under the water table is also referred to as the aquifer. In saturated zones, groundwater flows toward direction of surface streams or lakes, where discharge occurs. In the discharge zones, surface water flows out as springs or it joins a surface water body. The time required for water to flow through the ground to a discharge zone depends on the distance and rate of water flow (Roger et al, 1982).

Furthermore, the water table is the water found at the top surface of the saturated zone. This tends to replicate the shape of the land surface; it is lower below valleys, high below hills and there are always surface water bodies such as streams or lakes wherever the water table intersects the land. However, if there is lack of rainfall, this causes the water table to gradually flatten down; and the lakes, wells and streams all dry up as the water table lowered. The water from the rainfall soaks into the soil by infiltration and seeps downward because of gravity, this seepage continues down till it reaches the water table.

Figure1: Diagram showing saturated and unsaturated zones in groundwater                                                       (Roger, 1982)

An aquifer is a body of rock or sediment, which contains economically significant quantities of groundwater. It may form as a result of geological situation and may be found in a variety of different settings, normally their depth is limited to few kilometre, below this depth, pressure are high enough to seal pores, eliminating space for water. Aquifers may be confined, if its upper surface is not the water table but rather an impermeable layer of rocks such as Shale. On the other hand, if the upper surface of an aquifer is the water table itself, then the aquifer is called unconfined aquifer. This is well illustrated in Figure 2. It should be noted that not all aquifers have the same rate of recharge (Todd, 1959) Moreover, if the rate at which water is being pumped or drawn from the well is faster than normal or is in excess, it could reduces the water content in the aquifer and which can invariably reduces the water quantity in the well and allowing it to run dry. This does not only affect well, but all other nearby wells could be affected provided they are also pumping water from the same aquifer (Barbara, 2001) Furthermore, aquifers are replenishable even though, it might take several years for depleted aquifers to become replenished. If the withdrawal rate of the groundwater is more than the rate of recharge, this will gradually reduces the volume of the stored water. Recharging is the process of replenishing of groundwater. In the aquifer, compaction occurs as a result of mineral collapse when the pore water holding them apart is removed. This often leads to permanent damage, and reduces the amount of water the aquifer can ultimately hold. In addition, Urban development is another factor which can also cause groundwater depletion, this is not only by increasing the demand for groundwater but by increasing the impermeable ground cover; such as covering of the recharge area by roads, side walks, buildings and parking lots which can easily reduced the rate of replenishment (Barbara ,2001)

Figure 2: Diagram showing types aquifer in relation to the groundwater. (Source: McNeely et al, 2008).

Groundwater movement is such that it usually moves from areas of high pressure towards areas of lower pressure, so the direction of groundwater movement is more or less parallel to the surface of the land in most unconfined aquifers.(Close,1989). Most of the pollutants that cause pollution in surface water also account for the groundwater contamination. The commonest sources of groundwater pollution (in wells and springs) are municipal dumpsite, agricultural chemicals and untreated sewage. In addition, poorly designated landfills, toxic waste facilities, harmful chemicals leaking from the underground gasoline storage tanks can also seriously contaminate groundwater reservoirs (Beck et al, 1993).

1.1         Influence of hydrothermal alteration on groundwater

The circulation of a hot fluid through rocks causes hydrothermal alteration. The fluid may be a gas, a liquid or a mixture of both. The fluids in most cases carry a variety of substances in solution. Sometimes the fluid might be the groundwater that have been heated, because of its deep position in the earth crust and mobilised by broad gravity-related potentials (Hanor, 1979) Hydrothermal fluids seem to affect rocks selectively, some of the more susceptible rocks being limestone, mafic or glassy igneous rocks. Alteration is more intense along permeable zones such as open fractures, breccias, uncemented coarse clastic rocks, and rocks that are readily ‘hydro-fractured’. In rocks of moderate permeability, alteration is likely to be strongest near contacts with less permeable rocks, or at fault gouge that acted as a barrier to circulation. (Meyer and Hemley, 1967).

1.2          Common threats to the aquifer systems Many aquifers are subjected to serious threats which mostly affects the quality and quantity of the water obtained from the groundwater. Some of the major factors affecting the groundwater are; Depletion of quantity of available groundwater, which is also, refers to as groundwater over exploitation (pumping of excessive quantities of water out of an aquifer). This over exploitation occurs when there is continuous water-quality deterioration, water-level drawdown and ecological damage because of excessive pumping of quantities of groundwater from an aquifer (Simmers et.al, 1992). Climate change is another great threat to the groundwater systems. This normally induced by gas emission, from the greenhouse, which indirectly alters the recharge rates of groundwater, and it eventually leads to depletion of aquifer resources (Adams and MacDonald, 1998). Furthermore, when global sea levels were closer to 100m, during the glacial period, the water table in many regional aquifers became depressed far below the present levels and most of the groundwater in those aquifers froze to become permafrost at latitude above 40° (Younger, 1989). Large-scale mining activities such as mining include; limestone quarries, coal and clay mining, these and many others cause serious physical destruction of groundwater if they are not adequately monitored and regulated (Hobbs and Gunn, 1998).

1.3           Aim and Objective

The aim of this project is to determine the groundwater flow-net direction and to examine and assess the levels of some physical, chemical, biochemical, and microbial water quality parameters in Offa, South- west, and Nigeria. The objectives of this Independent study is to determine the suitability of the well water in study area by comparing the chemistry of the water with World Health Organisation (WHO) drinking water standards, with a view to determine their suitability for human consumption. The result of Offa well water samples will be compared with results of water of some cities in the world, such as Milan (Italy), Halifax (Canada), Oklahoma (USA), Coventry (UK), Faridabad (India), Lagos (Nigeria) etc.

1.4           Background Statement Groundwater exploration and exploitation have become a very important aspect of geology, and has a specialised branch namely; hydro geology this is due to the limited source of portable water for both domestic and commercial purpose.

Water is an abundant natural liquid mineral, which is readily available. However, the need of water for domestic supply, effluent disposal and cannot be met without appropriate and proper management of this resource. The ability of human being to render the surface fresh water inconsumable and expensive for the commercial uses necessitates the high demand for the exploration of the water in the subsurface.

Furthermore, water is very essential for direct human consumption. It is integrally linked to the provision and quality of ecosystem services. Domestic water is used for drinking, cooking, bathing and cleaning. However, access to safe drinking and sanitation is critical in terms of health most especially for children. For instance, unsafe drinking water contributed to numerous health problems in developing countries. Mark et al, (2002) indicated that approximately 100,000,000 incidents of diarrhoea occur annually as a result of ‘’unsafe’’ water consumption.

In addition, several studies exist on the relationship between ground (well) water and rock types in many parts of the world (e.g. Kawamura et.al.,1942;Davies and De Wiest,1961;Azeez,1971;Handa ,1975;Freeze and Cherry,1979;Okufarasin ,1984;and Adediji,1990).

CHAPTER TWO

2.0	     Basement Complex of Nigeria

The majority part of South-western Nigeria constitute part of the basement complex as shown in Fig. 3; the basement complex of Nigeria forms part of the Pan-African mobile belt and lies between the West Africa and Congo cratons and south of the Tuareg-shield (Black, 1980).

Generally, the basement complex rock of Nigeria is composed predominantly of magmatite gneiss, schist, quartzite, amphibole, charnockites, and calc-silicate and diorite rocks. There is also older granite suites consisting mainly of granite, granodiorite, and syenites (Rahaman, 1976).

More than 90% of Kwara-state is underlain by the Precambrian basement; the rocks include the migmatite gneisses, the metal sediment like schist, quartzite, and rock of older granite suites. These rocks have different aquifer potential based on their metrological characteristics and relative resistance of weathering and stress. They show strong foliation with other minor structure like joints and shear zones. The joint and fracture aid the development of extensive weathering profile in some places in Kwara-State such as Offa (Annor, 1992).

The main aquifer unit in a typical basement complex area is the weathered and fractured or jointed zone with thickness that varies from about 20m to 40m, or even more. Generally, the ground water flow system in the basement complex is localized depending on the presence of sufficient thickness and lateral extent of the decomposed weathered rock as well as the development of joint and fractures to a watershed. Lateritic soils are all product of tropical weathering. They are characterized by reddish brown or dark brown colourations laterites are generally found below hardened ferruginous crust of hard parts, lateritics soil are permeable (Acworth, 1987).

Figure 3: The map of Nigeria showing the basement complex (Adegoke et al, 1970)

Figure 4: Map of Nigeria showing the region of the study area in the South-west Nigeria (Oyawoye et, al, 1970)

2.1	       Location of the study area (Offa) Offa is located in South east of Kwara State, which lies within the South-western segment of the basement complex of Nigeria. It lies between Latitude 8º05’ N and Longitude 4º.44’E. The neighbouring towns include Patiagi, Ogidiri, Oyun, Ilorin and Ikotun. The population of Offa in 2005 census was 114,000 people. It is approximately 60km from Ilorin the State Capital .The vegetation in Offa is Savannah with temperature ranges between 25°c to 30°c. The major Climatic seasons are rainy season, which begins in March or April, and ends in October and the dry season, which begins in November and ends in March or April. The city is noted for its weaving, dyeing, trading and farming.

The wells studied were hand-dug and are uncased, but enjoyed the support from the firm soil. Their depths range from 4-15 metres and depend on the topographical levels. Most of the wells have concrete rims and are covered with painted metal plates, as shown in figure 6, but few were left opened (Fig.5). In addition, the environmental conditions around each well vary widely.

Figure 5: Picture of opened Hand-dug well in Offa Township.

Figure 6: Picture of well with concrete rim and covered metal plate

The study area (Offa) has few industries ranging from Foods (Okin Biscuits), textiles factories, farming (crops and animals), to various road side Vehicle repair garages. Significant amount of industrial and domestic waste generated are used in reclaiming land, whilst considerable quantities are dumped on the municipal waste dumpsites within the study areas. There are two major dumpsites in Offa. The one closer to the St James church (TL16) in table 3.1, is an old or abandoned dumpsite. Barb wire has been erect round the site to prevent people from dumping refuse on the waste site, while the other dumpsite near Bale’s compound (TL3) tends to be the main functioning municipal dumpsite in Offa Township as shown in figure 7. This dumpsite comprises of all sort of waste materials ranging from dead animals, waste metallic materials, plastic materials, car batteries, dead plants, defecate from human being and animals, waste chemicals from local textile industries, amidst harmful waste materials.

Figure 7:       Picture of Municipal dumpsite in Offa

Eventually, such wastes later provide pollutants and contaminations ranging from toxic elements, metals, and organic and inorganic species and down to cations such as chloride, potassium and so on. In addition another main source of pollution in the study area are waste chemicals from different agricultural fields in Offa areas, since farming is one of their main source of income and livelihood. Such agricultural waste includes pesticides, herbicides, fertilizers and some other agricultural waste which are all refer to as non-point source pollution. These contaminants easily gain access to local aquifers either through interaction with the surface water bodies or directly through infiltration (Vrba et al, 1994).

Figure 8: The map of kwara state showing the Offa Township (Annor, 1986)

2.2	     Geology of the study area

Six rock types underlie Offa area, which include; Pegmatite, Schist, Migmatite, Gneisses, Quartzite, Charnockitic. The deformation pattern and metamorphic imprint of the area cannot be exactly described, and the most dominant rock types are Schist that is of paleo -Proterozoic age. (Annor, 1986)

The crystalline basement exposure within Offa is very rare, throughout the field work and mapping in Offa, only one outcrop was encountered. As a result, the actual rock type, deformation pattern and metamorphic imprint of the area cannot be exactly described due to lack of outcrop exposure. The study area is an unexposed area that might be because of the in-situ chemical weathering. The type and degree of weathering in this study area is determined by the prevailing humid tropical climatic condition, also the essential meta-sedimentary schist are highly susceptible to insitu chemical weathering and because of their fine grained size intense weathering led to clay. 2.3	      Hydrogeology of Offa

The petrology of rocks determine the hydro geological characteristics of most areas, the ground water potential in Offa appears to improve with induced secondary permeability derived from fracture, joint and solution channels. The main controls of the occurrence and flow net rates of ground water are the porosity and permeability of the groundwater reservoir, and these two controls are generally lacking in the study area due to its location within the crystalline basement (Annor, 1989).

The study area is drained mainly by run off streams like Agun stream and Atan stream as shown in fig.9 below, which drain into the ground, and recharging the reservoir. The drainage pattern is dendritic. The soil type in the study area is Lateritic soils, which are all product of tropical weathering. Lateritic soils are generally well sorted and are permeable which makes a good reservoir even though the soils are not highly porous. The wells studied in Offa area are hand–dug as shown in fig.6, with water depths range from 4 to 15 metres depending on the topographical levels. The average depth of the water in Offa is not lower than the type of aquifer that operates in this, and this is termed regolith aquifer, which is lithologically controlled. The aquifer has good pore space that permits free flow of groundwater, and it is an unconfined aquifer, because there are no impermeable strata overlying it.

2.4	 Vegetation and Climate

The study area is characterized by rainy season, which starts in April or May and ends in September or October with the inherent month of August break. Offa is at the margin of Guinea savannah and tropical. The difference in climatic conditions contributes to the flow of groundwater movement. The vegetation of the area is characterized with big trees, tall grasses and shrubs, which remain evergreen throughout the year .The temperature ranges from 25ºC to 30ºC. There is intensive chemical weathering in Offa that occurs as a result of the climatic condition in the area (Oyetakin, 2000).

2.5	Drainage and Topography

Offa area is drained mainly by run off streams like Agun stream and Atan stream that drain into the ground re-charging the reservoir. The drainage basin is dendritic. The study area is an undulating land with the topography ranges from 432m and 384m height.

Figure 9:     The map of drainage pattern in Offa, Nigeria. (Source: Oyetakin, 2000).

2.6.	 Lithologic description of the rock sample in the study area.

The outcrop found at Akewusola’s residence in Offa area is a gneiss rock with approximately 20-25m in thickness. It is a foliated rock with uniformly distributed domains, which are small to influence a textural aspect when viewed from a few meters away .When I examined the rock sample with a hand lens, I discovered that, the domains consist of groups of certain grains. Most, or all, of the rock is granoblastic and cleaves only crudely parallel to the foliation. This gneiss was formed by deformation acting throughout grain growth, which is characterized by strongly lineated and often-plicated domains, with micas, amphiboles, and other platy or linear grains lying parallel to foliation and lineation (Compton, 1985).

Figure 10: Picture of the rock sample found at Akewusola’s compound. (Size: 11cm by 7cm).

Generally, gneisses are formed mainly by grain growth after deformation. The platy and elongate minerals are orientated more or less randomly or grains that are usually platy or prismatic may be nearly equidimentional. (Moore, 1973) The gneiss has a pegmatitic vein, cutting discordantly through it. The pegmatite vein has strike and dip angles of 313º, 47ºW respectively. The vein has thickness of about 12 cm, and the crystal size ranges between 1.0-1.2 cm with milky to whitish colour.

The rock has a mineralogical variation ranging from quartz, feldspar, biotite with some opaque minerals, and the minerals are banded. There are joints with orientation 323º, 322º, 320º and the joint cuts across the striation and lineations.There are quartz vein intrusions, which are vertically inclined with many fractures. The veins trend in same direction on the pegmatite.

2.7.	 Petrography description of the rock sample.

The sample collected were analysed at the Laboratory of Department of Geology at the University of Ibadan. The results show that gneisses have fine to medium grain size and the mineral identifiable includes quartz, feldspar, mica, plagioclase, microcline, muscovite and apatite. This is shown in Figure 9

Plagioclase                           30% Microcline                             5% Muscovite                             4% Apatite                                  1%

Magnification 15x

Figure 11: The diagram showing the thin section of fine medium grained Gneiss Found at Akewusola’s compound (TL15) in Offa

CHAPTER THREE

3.0	 Method of investigation.

Nineteen (19) water samples were collected from eighteen (18) hand-dug wells, selected randomly at different localities. One of the samples was collected from Agun stream that is one of the two major streams in Offa area, I was unable to collect any sample from Atan stream due to lack of accessibility. However, the well water samples were collected randomly from different locations; covering the entire Offa Township as shown in figure 9. Three (3) samples were taken from each hand-dug well. In order to obtain results that are more accurate and prevent the sample collected from contaminated which could invariably affect the desired results. The measurement of the water table, water depth, surface elevation, and the bearing of each well are also tabulated in table 1 below

The well water samples from each location were collected in clean and well-rinsed 1.5 ml plastic bottles, which were temporarily stored in a plastic cooler. At the end of each day, the samples were stored in a refrigerator at 4°C in order to keep them at cool temperature and to reduce its exposure to sunlight or heat, which could also affect or influence the result, in order to obtain the desired result; the samples were prevented from contamination. The 19 water samples collected were analysed at Lagos State University Hospital Laboratory, Lagos, Nigeria using Atomic Absorption Spectrometer (Perkins imer 306) with wavelength of 285. Flame photometer was used for measuring potassium, sodium and calcium. Mohr Argentometric technique or method was used to determine the electrical conductivity and pH measurements, while titration methods were used to measure total hardness and alkalinity. The analysis for the organic pollutants was not carried out due to unavailability of facilities. The values obtained are reported in Milligrams per litre (Mg/L) except for electrical conductivity, which is in micro siemens per centimetre (µs/cm).In addition, during the entire period of this analyses, all the equipments and instruments used were calibrated in accordance with the guidelines from the manufacturers. Figure12: The GIS map of Offa showing the municipal dumpsite, Atan stream and Agun stream. Table 1:     The table showing well locations and measurement

Well numbers	Location	Latitude (Degree)N	Longitude (Degree)E	Surface elevation(ft)      (SE)       	Water Depth(ft) (WD)	Water table(ft)  (WT) TL1	Ogidiri LGEA school	8.16	4.74	28	14	14 TL2	Ijagbo Baptist Road	8.15	4.74	26	15	11 TL3	Bale’s compound (200m away from the dumpsite)	8.14	4.74	30	13	17 TL4	Ijagbo Baptist School	8.15	4.74	58	10	48 TL5	Ijagbo Baptist Church	8.14	4.73	39	11	28 TL6	Adekunle’s compound 100m away from Okin Biscuit factory)	8.13	4.74	48	13	35 TL7	Sample collected from Agun stream	8.13	4.72	No data	No data	No data TL8	Offa secondary school	8.13	4.71	61	9	52 TL9	Popo road Offa left roadside	8.15	4.73	64	9	55 TL10	Popo road Offa right roadside	8.15	4.73	65	9	56 TL11	Olofa palace King’s palace	8.16	4.71	66	11	55 TL12	St Claire’s Anglican college	8.12	4.72	67	8	59 TL13	Offa specialist Hospital	8.11	4.72	65	9	56 TL14	Well 30m away from Atan stream	8.18	4.72	68	6	62 TL15	Akewusola’s compound	8.13	4.71	67	7	60 TL16	St James CAC school (100m away from old dumpsite)	8.14	4.71	69	5	64 TL17	Owode market area	8.16	4.70	69	6	63 TL18	Olagunju’s residence	8.18	4.71	70	4	66 TL19	Adewuyi’s residence	8.17	4.69	71	4	67

3.1	Measurement of Hand-dug Well

The measurement of the water depth in the well was carried out with a Dipper. This is a graduated tape attached to a probe, where a simple electrical circuit is completed when it gets in touch with water in the well). It is the most common modern equipment for measuring depth to water, when the Dipper gets in touch with water, it is alerted by making sound of a buzzer and the bulb will be illuminated, indicating a complete circuit. The Dipper tape is put down the borehole until a signal is detected and the depth to water is recorded to the nearest centimetre. In addition, other equipment used includes a measuring tape, rope and a drawing bucket (for collection of water from the well).

3.2	 Method of Determination of groundwater flow-net direction

The groundwater flows from high-pressure areas towards low-pressure areas. The direction of groundwater movement is almost parallel to the surface of the land in an unconfined aquifer. Moreover, groundwater normally moves toward, and eventually drains into streams, river and lakes (Todd, 1959). The movement of groundwater in aquifers does not always mirror the flow of water on the surface. Therefore, the groundwater flow-net in Offa and the hydraulic gradient within an unconfined aquifer can be determined using the following three (3) steps or methods.

Step1. The water table (WT) elevation at three (3) locations that are widely apart should be determined. This can be done by subtracting the depth to water (DW) from surface elevation (SE) at each well.

Figure 13 (a): Diagram showing groundwater flow-net direction. Step2:

All the well locations derived from the diagram in figure 13(a) are shown in figure 13(b) below. Using diagram from figure 13(a) above, to find the differences in the water table (WT) elevation between each of the wells by subtracting the water table (WT) elevation of a well with a higher elevation from the water table elevation of a well with a lower elevation on each of the straight line connecting the wells. The differences in these elevations are divided up into equal increments. Water table elevation levels have been placed on the figure by adding the initial water level to each increment draw, then draw straight lines connecting or joining the increments, which have the same values. These connecting lines represent the water table contours (Zhang et al, 2000).

Figure 13(b): Diagram showing groundwater flow-net direction.

Step3: It is observed from the connecting lines in fig13b that, groundwater flows from higher elevation to lower elevation in the direction of maximum change in elevation. The line perpendicular to the straight lines that connect the elevation increments indicates the direction in which the groundwater flows In addition, the hydraulic gradient, this is the vertical change in groundwater elevation over horizontal distance, in the direction of groundwater, flow. This can be calculated using the following equation (Price, 1996).

Hydraulic gradient =      water table elevation change (in direction of flow) Horizontal distance between measurement points.

3.3    Method of Hydro chemical assessment

The parameters analysed include; pH, total dissolved solids, (TDS), electrical conductivity (EC), total alkalinity (TA), total hardness (TH),as well as cations and anions concentration, such as phosphate ion (PO43-),sulphate ion (SO42- ),Nitrate ion (NO3- ), Calcium (ca²+ ), Sodium (Na²+ ), Potassium (K+), Chlorine (Cl-). The samples were collected from 18 wells water samples and 1 sample from Agun stream which were analysed (in April shortly after the fieldwork in Offa, Nigeria) using pH meter, Electronic conducting meter (EC) and atomic absorption spectrometer respectively. These analysis were carried out in a standard laboratory.

CHAPTER FOUR

4.0	 Interpretation of Results

4.1	  Result of the Chemical Analysis of Offa samples

The chemical analysis of the samples collected from the study area was carried out at Lagos State University Hospital laboratory, Nigeria using Atomic Absorption Spectrometer (Perkins imer 306) with wavelength of 285. The values obtained are reported in Milligrams per litre (Mg/L).The result of the analysis is shown in table 2 below.

Table 2: Results of the Analysis of water samples from Offa groundwater.

Nd:  no data.

4.2	Presentation and interpretation of Results

The results of the analysis in table 2 are compared with the recommended standard for drinking water by World Health Organisation (WHO) and Federal Environmental Protection Agency (FEPA), Nigeria that is shown in table 3 below. The comparison will indicate if the water in Offa area is suitable and good for drinking or hazardous to human health.

Table 3: W.H.O and F.E.P.A recommended standard values for portable Water, (W.H.O, 2008).

PARAMETERS	OFFA SAMPLES (RANGE)	     W.H.O     STANDARD FEPA RECOMMENDATION 1	pH	5.15 - 6.92	6.5-8.5	6.5-8.5 2	Temp °C	25.1 - 30.0	nil	nil 3	EC (µs/cm)	139 - 863	1000	950 4	TDS (mg/L)	77  -  878	500	500 5	TA (Mg/L)	10 -  134	200	200 6	TH (Mg/L)	10 -  81	200	<50 7	PO43- (Mg/L)	  0  -  0.7		<50 8	SO42-  (Mg/L)	  0  - 36.1	400	500 9	Pb   (Mg/L)	Nd  -  0.4	5.0	10.0 10	Zn   (Mg/L)	0.01 – 0.4	5.0	10.0 11	NO3-  (Mg/L)	0.01 – 1.5	10.0	10.0 12	Cl-   (mg/L)	0.44 – 99.3	250	250 13	Na²+ (Mg/L)	1.69 - 63.43	200	200 14	K+ (Mg/L)	0.63 -  59.0	200	200 15	ca²+ (Mg/L)	6.25 - 186.2	250	250

W.H.O        World Health Organisation FEPA         Federal Environmental Protection Agency Nd              No data 4.3	     Interpolated/Contour Map Presentation and Interpretation The plots of the examined parameters as well as the interpolated contour maps of different ions as shown in figure 14a to figure 32b below give explanations to the interpretation of the samples analysed. Moreover, these indicate that some of the water samples have high concentration of calcium, chloride, sulphate, Nitrate, Electronic conductivity, Total dissolved solid and other ions present in the water samples. Some of these are found in areas like Olofa’s palace, St James School, Adekunle’s compound, Ogidiri LGEA and others, which have been discussed earlier. The distribution of these ions and metals in Offa areas are also interpreted in the interpolated plots. The plots show areas with high and low concentrations of each ion and metal as well as areas with high concentration could occur because of the municipal dumpsite within the area. Waste products and pollution from the nearby factories, agricultural waste products and probably the chemical composition of the rocks that formed part of the sampled areas.

4.3(i)		 Sodium (Na2+) Figure 14a: Plot showing the concentration of Na2+  in the well water sample.

The highest concentration of sodium was found in well TL16 (St James CAC school) which is 100m away from the old dumpsite and the lowest concentration was found in well TL17 (Owode market area).The concentration of sodium are not above detection level and this was maintained almost in all samples collected and the taste of sodium was not determined. The high concentration in TL16 might be due to proximity to domestic and industrial waste that might have been deposited on the old dumpsite in a considerable quantity. Such waste might provide pollutant, associated with putrescible materials and metals, which might be harmful to human health. Apart from the dumpsite refuse, the rock forming minerals can also be the main sources of sodium in the groundwater and under certain conditions. Some clay minerals may release exchangeable sodium ions (Carla, 2000). The sodium concentration in the well samples has very insignificant effect on human health.

Figure 14b: Interpolated G.I.S contour map of Na2+ concentration in the well samples

4.3(ii)		Potassium (K+)

Figure 15a: Plot showing the concentration of K+  in the well water sample.

The highest concentration of potassium was obtained from sample collected at Agun stream (TL7) while the lowest concentration was obtained from the well at Popo road Offa (TL10) .There are detectable amount or concentration of potassium at St Claire’s Anglican college (TL12) and St James CAC school (TL16) which is about 100m away from the old dumpsite. Although, the high amount of potassium discovered at TL7 is not harmful for human consumption, and it is in line with recommendation standard by WHO and FEPA. The high concentration of potassium in Agun stream could be because of application of herbicides on near by agricultural fields and farms that might be seeping into the groundwater and near by Agun stream (Vrba et al, 1998).

Figure 15b: Interpolated G.I.S contour map of Phosphate concentration in the Well samples

4.3(iii)	Calcium (Ca2+)

Figure 16a: Plot showing the concentration of Ca2+  in the well water sample.

The highest concentration of calcium was discovered in well sample at Adekunle’s compound (TL6) which is about 100m away from the dumpsite that consist of domestic and industrial wastes. The lowest calcium concentration was found at Owode market area (TL17), and the result of the chemical analysis of samples from Olofa’s compound (TL11) and Offa specialist Hospital (TL13) revealed that calcium content is within WHO and FEPA maximized permissible level for drinking water. The results obtained from the analysis shows that calcium is the most abundant dissolved cation in the well water samples in the study area. Calcium in crystalline rock is supplied by feldspar, pyroxene and amphiboles. The low calcium concentration despises by the analysis result, could be linked to the low ratio of bicarbonate, to free carbon IV oxide (CO2) in igneous and metamorphic rocks. This makes the calcium carbonate which dissolves in the groundwater minimal and such calcium has no significant effect on human health and not harmful for human consumption (Bishop et al, 1993).

Figure 16b: Interpolated G.I.S contour map of Ca2+ concentration in the well samples 4.3(iv)	Chloride (Cl-)

Figure 17a: Plot showing the concentration of Cl- in the well water sample.

Chloride is an anion, that is not a very reactive solute found in groundwater systems and it has few natural mineral sources. High concentration of chloride is derived from where the system and halite encountered by flowing groundwater (Elliot et al, 2001). In Offa area, chloride concentration has its highest value in TL3 (Bale’s compound) which is about 200m away from the dumpsite, while the lowest concentration was discovered in TL11 (Olofa’s palace).The values of chloride obtained in all of the wells sampled in Offa areas are not above the WHO recommended standard value of 250mg/L. The chloride concentration are less than WHO recommended acceptable level, the low chloride concentration in Offa areas indicate that pollution of groundwater was at its minimal and are not threat in any way to human health in Offa township. Moreover, high concentration of chloride in deep groundwater may indicate; dissolution of evaporate rocks at depth, an ancient history of evaporation in the near surface environment, and enrichment of solute concentration because of natural membrane filtration. Membrane filtration mostly occurs at great depths in some sedimentary basins, especially where the natural head gradient forces groundwater to flow through a mudstone bed, which has tiny pores that might prevent the migration of solutes. Most ancient groundwater found at depth in sedimentary aquifers is mostly rich in chloride and this water might have gained access into the aquifer during periods of the quaternary when the position of sea and land were different from the current state (Freeze and Cherry, 1979).

Figure 17b: Interpolated G.I.S contour map of Cl- concentration in the well Samples 4.3(v)	Cations Figure 18: Plot showing the concentration of Cations in the well water sample.

The major cations mostly found in groundwater are calcium, magnesium, sodium and potassium and they are always present in high concentration. The main source of these cations is the dissolution of minerals present in the soil and bedrock. Dissolution of carbonate minerals, such as calcite (CaC03) which consists of high concentration of magnesium and dolomite, both of which are surplus in limestone environments are also source of calcium and magnesium. Some silicate minerals are also sources of calcium and magnesium in groundwater for instance, ultra basic and basic igneous rocks, dissolved calcium and magnesium can also be obtained from the weathering of anorthitic plagioclase, diopsidic pyroxene and forsteritic olivine (Hem, 1985). In igneous rocks, hornblende and biotitic mica are common source of calcium and magnesium. Sodium is present in most plagioclase feldspars and in many acidic igneous rocks. Sodium and potassium do not form carbonate minerals because they are soluble, but are present in halite (Nacl) and sylvite (KCl) which are constituents of ancient evaporate which are formed under hyper arid condition, and when these minerals enters the groundwater, they dissolve rapidly producing thousands of mg/l of sodium and potassium solution (Younger,2006).

4.3(vi)	Sulphate ion (S042-).

Figure 19a: Plot showing the concentration of SO42-  in the well water sample.

The concentration of sulphate obtained from the Offa well water samples analysed ranging from 0.00mg/l to 36.1mg/l .The sulphate concentrations obtained was within the World Health Organisation drinking water guideline. However, increase in the sulphate levels were insignificant, the differences in the sulphate levels in the well water may be attributed to the Hydrogen sulphide (H2S) gases emitted from the dumpsite because of frequent contact of the air with the water surface, which could have resulted into the high dissolved sulphate in the well water (Das Gupta et al, 1997).

Figure 19b: Interpolated G.I.S contour map of SO42- concentration in the well samples

4.3(vii)	Nitrate ion (NO3-).

Figure 20a: Plot showing the concentration of NO32-  in the well water sample.

The occurrence of NO3¯N (Nitrate ion) in the groundwater might have resulted from the improper discharge of the domestic sewage. It is observed that the concentration of nitrate ions in the Offa groundwater might be from the point sources such as sewage disposal and the different rates of concentration of NO3¯N in the well waters might be because of denitification and the occurrence of precipitation in the study areas (Brunett and Madison, 1985).

Moreover, also leaching of fertilizer nitrogen is a likely cause of nitrate concentrations in groundwater, other possible sources of nitrate in groundwater also include; evaporate deposits, irrigation with wastewater, manure dung heaps, geological sources, atmospheric deposition and unsewered sanitation (Madison et al, 1985). Figure 20b: Interpolated G.I.S contour map of Ca2+ concentration in the well samples 4.3(viii)		Phosphate (PO43-).

Figure 21a: Plot showing the concentration of (PO43-). in the well water sample.

The presence of phosphate ion in the Offa well water samples indicate and increase the possibility and growing of troublesome algae in the groundwater in the study area. The presence of phosphate in the well water could be attributed to agricultural activities in Offa area (Punmia, et al, 1998). The concentrations of phosphate in the analysis results ranges from 0mg/l to 0.7mg/l, this shows that the concentration of phosphate ion in the water samples is low and it is below the World health Organisation stipulated guidelines. This low concentration of phosphate from the result of the analysis indicates that the amount of phosphate ions available in the well water samples in the study area is not a threat to human health.

Figure 21b: Interpolated G.I.S contour map of (PO42-) concentration in the well samples

4.3(ix)	Anions

Figure 22: Plot showing the concentration of Anions in the well water. Sample. (Chloride, Sulphate)

The major anions found mostly in groundwater includes; bicarbonate, sulphate and chloride. They mostly get into the aquifer through rainfall. There are two main sources by which sulphate gets into groundwater and they are; weathering of gypsum and or anhydrite and weathering of sulphide minerals mostly pyrite (Price, 1996). The result of the analysis in Offa shows that of all the anions, chloride is the dominant anion with average value or concentration of 31.1mg/L. The highest concentration of sulphate was obtained at St Claire’s Anglican college (TL12), which is a bit closer to the dumpsite .Phosphate of all the anions has very insignificant value, with the highest value obtained at Ogidiri LGEA school (TL1) and the average concentration of phosphate is 0.16mg/L. The results of these anions are within the WHO recommended value.

4.3(x). Total dissolved solid (TDS)

Figure 23a: Plot showing the concentration of TDS in the well water sample.

The results obtained from TL3, TL4, TL6, TL12 show that there are high concentration of Total dissolved solid, which is more than the maximum WHO recommended standard value of 500mg/L. The high concentration could be because of human activities such as spillage of pesticide or insecticide through the agricultural or farming activities, which is one of the main occupations of Offa indigenes. The high TDS concentration in TL18 could be linked with the municipal dumpsite near TL3, which can cause variation in concentration of groundwater in Offa area. The high concentration of total dissolved solid in the samples collected in the study areas indicates that some of the wells are not suitable for drinking purposes, unless they are properly treated. The high concentration of total dissolved solid detected can lead to serious effects such as gastro intestinal irritation (GII) (Plunkett, 1976).

Figure 23b: Interpolated G.I.S contour map of TDS concentration in the well samples

4.3(xi). Total Alkalinity (TA)

Figure 24a: Plot showing the concentration of TA in the well water sample.

The results from the analysis show that the highest value of total alkalinity was 134mg/L, which was obtained at Adekunle’s compound (TL6) while the lowest value of 10mg/L was recorded at Olofa’s palace (TL11). The alkalinity shows the level of carbonates, bicarbonate and hydroxyl groups in well water samples. Hydroxide is very uncommon to natural water and for the samples analysed, there was no phenolphthalein alkalinity recorded. The total alkalinity average value of 61.7mg/l was recorded, and it was observed, that groundwater sampled with low alkalinity values influences low pH values (Plunkett, 1979).

Figure 24b: Interpolated G.I.S contour map of TA concentration in the well Samples

4.3(xii). Electronic conductivity (EC)

Figure 25a: Plot showing the concentration of EC  in the well water sample.

Conductivity is the ability of given water to conduct electricity and it is directly proportional to the amount of dissolved charged ions, which it contains. Ground waters normally possess high concentration of conductivity; mostly the aquifers in hot regions or countries and this could be result from direct evaporation from the water table, and especially in region, that lies less than 2m below the ground level. Electrical conductivity in aquifers within low land areas range between 150-1000uS/cm, which shows an increase in the total solute content resulting from the dissolution of common minerals, where minerals, that are highly soluble like gypsum or halite, are present (Younger,2006).

The concentration value of electronic conductivity discovered in the well water sampled, reflected the total dissolved solid concentration. The highest value of EC was 863mg/l which was discovered at Adekunle’s compound (TL6) while the lowest value was 139mg/l and was found at Popo road Offa (TL10) .The average value of 485mg/l was recorded and this value is still in accordance with WHO recommended standard value of 1000mg/l. So therefore, the percentage of electronic conductivity in the groundwater in Offa does not possess any threat to human health in the area. However, the highest concentration obtained in TL6 that is closer to the dumpsite could be because of leaching of contaminants from the municipal dumpsite toward the groundwater source. Figure 25b: Interpolated G.I.S contour map of EC concentration in the well samples 4.3(xiii)	   Total hardness (TH)

Figure 26a: Plot showing the concentration of PO43-  in the well water sample.

This is the measure of calcium (Ca) and magnesium (Mg) levels present in groundwater. The highest value of TH was obtained at Adekunle’s compound (TL6) with value of 81mg/l while the lowest value of total hardness of groundwater analysed was found at Ogidiri LGEA School (TL1). The mean or average value of TH recorded in the study area is 45mg/l.

The result showed that the total hardness values were not more than the WHO recommended standard value shown in table 4.2 above. However, an article from Canadian environmental Agency (1979) classified water having 0 -30mg/l caco3 as very soft, 31- 60mg/l as soft, 61-120mg/l caco3 as moderately soft, 120-180mg/l as hard, and > 180mg/l as very hard (McNeely and Dwyer, 1979). Based on this classification, It is discovered that most of the well sampled in Offa areas, fall between very soft and such wells that fall into this class includes; TL1, TL4, and TL10, soft water includes; TL2, TL3, TL5, TL7, TL9, TL11, TL13, TL14, TL15, TL17 and TL19, while the remaining of the wells fall into moderately soft class (61-120mg/L). Goski and Taderz (1981) reported that water hardness ranged from 149 to 419mg/l. Hardness makes water useless in laundry work and causes excessive scale formation.

Figure 26b: Interpolated GIS contour map of TH concentration in the well Samples 4.3(xiv)	     Lead (Pb) Figure 27a: Plot showing the concentration of Pb in the well water sample. Figure 27b: Interpolated G.I.S contour map of Pb concentration in the well Samples 4.3(xv)	    Zinc (Zn). Figure 28a: Plot showing the concentration of Zn in the well water sample. Figure 28b: Interpolated G.I.S contour map of Zn conc. in the well samples Figure 29: Plot showing the concentration of Toxic element in the well water sample. (Pb and Zinc).

Toxic elements such as Lead (Pb) and Zinc (Zn) gain entry into the water system through industrial effluents and dissolution of minerals and the concentration of lead and zinc in the well water samples are very low, and this could be linked to the absence of major industries in the study area (Ajayi et al 2001).

4.3(xvi)		Heavy metals Figure 30: Plot showing the concentration of Heavy metal in the well water Sample (EC, TDS, TH, and TA).

The high concentration of ions because of leaching of the contaminants or due to the geology of the area might have contributed to the high values of heavy metals obtained, and this could be linked to dissociation from bedrocks through which the groundwater flows (Ajayi et al, 2001). The heavy metals such as TDS and conductivity were higher in some wells which are closer to the dumpsite, such as TL6 and this high concentration could be due to the leaching of contaminants from the dumpsite moving down towards the groundwater source or due to the presence of high dissolved minerals from the domestic sewage containing heavy metals discharged in the well surroundings, because most of the households do not have septic tanks (Beck et al, 1993). In contrast, some wells such as TL11 (Olofa palace) and TL1 (Ogidiri L.), have low concentrations of heavy metals. This high concentration might be due to the presence of soil organic matter, which might have combined with the toxic metal cations such as Cr, Zn, Pb, and Cd and invariably reduced the availability of toxic metals in those wells (Beck et al, 1993). 4.3(xvii)		pH

Figure 31a: Plot showing the concentration of pH in the well water samples

The result from the analysis reflected that useful values of water pH, suitable enough for drinking, agricultural and domestic purposes were obtained from the well water samples. All the values of pH recorded in the study areas are within the World Health Organisation recommended standard. However, some higher values of pH discovered in some wells within the surrounding of the municipal dumpsites could be linked to the discharge of Ammonia, methane and carbon dioxide during decomposition of the waste materials, which through leachates enters the groundwater through the aquifers (Nyer, 1992). The low values of pH of water detected from well TL10 and few other wells could be because of amino acid compounds and sulphur from animal and human excreta (Ojelabi et al, 2001).

Figure 31b: Interpolated G.I.S contour map of pH concentration in the well samples

4.16	Temperature

Figure 32a: Plot showing the concentration of Temperature in the well water. The average temperature in the study area is 27.55ºC. During the wet or rainy season the temperature become lower, and there is rapid increase in the quantity of the groundwater, in contrast, the wells dry up during the dry season, because of high temperature. This usually results into high shortage and scarcity of groundwater to the people, plants and animals in this Offa environment. In addition, the temperature of incoming recharge waters is shown in the groundwater temperature, which increases with depth, and the deep-seated groundwater, might be warmer than those lying close to the water table. Figure 32b: Interpolated G.I.S contour map of Temperature concentration in                                             the well samples

4.4           Hydro chemical Facies

The water in the well at Ogidiri LGEA School (TL1) has calcium, Sodium as the dominant cations and it has the highest concentration of phosphate while the remaining elements are relatively low in concentration. Despite these concentrations, the water is still suitable for drinking.

Subsequently, water samples collected from; Agun stream, Offa secondary School, Popo roads, Olofa palace, St Claire’s Anglican college, Offa specialist Hospitals, well near Atan stream, Akewusola’s compound, St James CAC school, Owode market area, Olagunju’s residence and Adewuyi’s residence, all have relatively low concentration of cations, anions and other parameters. However, I observed that the water collected from Agun stream is the purest comparing to the samples from other wells in Offa area. The stream water consists of extremely low concentration of the harmful and toxic elements and the water is very pure and clean for human consumption. While some wells like St Claire’s and adewuyi’s residence have relatively high concentrations of Electronic conductivity while Olofa’s palace has highest concentration of Lead (Pb) which is still within WHO recommended standard.

Furthermore, well water from Bale’s compound (TL3) has dominant concentration of chloride, total dissolved solid and it has very high concentration in calcium, sodium, electronic conductivity, total hardness, total alkalinity, and zinc, which indicates that the water from Bale’s compound is unsuitable for human consumption without proper treatment.

Lastly, the water sample from Adekunle’s compound (TL6) has the highest concentration of calcium, potassium, Nitrate, electronic conductivity, total hardness, total alkalinity and relatively high chloride, sodium, sulphate, and total dissolved solid. The high concentrations of these ions strongly indicate that the well water from Adekunle’s compound is unsuitable for human consumption despite the fact that some of the elements are not more than W.H.O recommendation. In addition practical experiment was carried out to compare the water in Adekunle’s compound (TL6), to some other samples from different wells, such as TL1, TL10, and TL4, using washing detergent (Omo). It was discovered that the amount of leather formed from water in TL6 was extremely low compare to the water from other afore mentioned wells. This strongly indicates that the water from TL6 is very hard, and can cause great damage to human health. However, no causality has been recorded yet, because of drinking this water, but it poses a great threat to people consuming it, unless it is properly treated.

However, the following could be the causes of high concentration in the well water sampled; closeness of the well to the municipal dumpsite, human influence through agricultural activities, unsewered sanitation and geological sources such as dissolution of minerals present in the bedrock and soil.

CHAPTER FIVE

5.0	   DISCUSSION

5.1        Comparison of Offa result with some other urban   groundwater pollution case histories

Similar studies have been carried out in some urban areas in different countries and also in different towns and cities within Nigeria, examples of which are; Ikem (2002) discovered relatively high major ions, which includes Nitrate and COD in groundwater near dumpsite in Ibadan and Lagos, Adekunle et. al, (2007), discovered that Lead, Nitrate exceeded the World Health Organisation recommended standard for portable water in a sampled well which is closer to the pollution source. In addition, Yusuf (2007) discovered relatively high values of Total dissolved solid and electronic conductivity in samples collected in Lagos metropolitan, and this was claimed to be because of pollution from the industries. Moreover, Ayejuyo (1994) discovered Aldrin, Lindane, PCBs and endosulfan in the groundwater from Ibadan city, and lastly, Ipinmoroti (1993), Adeleke and Okoye (1991) found good quality well groundwater from some selected locations in Akure, Ondo state, Nigeria .However, many other studies from different cities in the world, would also be discussed later in this chapter.

Table 4: Case history of some urban groundwater pollution (Adapted and modified from Yusuf, 2007).

Country	Cities	 Elements	Author Germany	Bielefied	Org,EC,TH,Mn,Cl,COD	Dummer & Van Stranten (1988) United Kingdom	Coventry	CHS	Gosk,et al (1990) India	Faridabad	Cr	Handa et al (1983) Canada	Halifax	Cl in de-icing salts	Cross (1980) Nigeria	Lagos/Ibadan	COD, metals	Ikem et al (2002); and Sangodoyin et al Nigeria	Lagos	TDS, EC	Yusuf (2007) Nigeria	Ede	K	Adediji and Ajibade(2005) India	Ludhiana	Metals	Kakar and Bhamagor(1981) USA	Long island	NO3-	Flipse et al (1984) Mexico	Merida	Bacteria	Cruickshank et al (1980) India	Madras	Metals, majors	Somasundarama et al(1991) Italy	Milan	Org	Cavallero et al (1985) USA	Milwaukee	Cl-, SO42, Bacteria	Eisen and Anderson (1980). USA	Nassau count	NO3-	Katz et al (1980). USA	Oklahoma	NO3-	Philips et al (1997). Uganda	Uganda	Cl, Fe, Zn, Al and Mg	Taylor et al (1993).

EC=Electrical conductivity, COD=Chemical oxygen Demand, CHS=Chlorinated Hydrocarbon Solvents, TH=Hardness, Majors=Na2+, K+, Ca2+, Mg, Cl-, SO42-, HC03-, Metals=Heavy metals, org=Organic determinant.

The results obtained from the Offa well water sample analysed, showed that all the presence anions, cations, heavy metals and toxic elements are within the guidelines stipulated by Federal Environmental Protection Agency (FEPA) Nigeria and World Health Organisation (WHO) for potable water. However, some related studies carried out in other parts of Nigeria by individual, government and research teams, showed high concentrations of some water pollutants.

The study carried out by Agbaje and Sangodoyin in Ibadan, Oyo state that is a neighbouring state to the study area, showed that leachates from the nearby Abattoir that was about 250 m to their sample areas had great influence on the pollutant concentrations of the ground in the area. They detected concentration of toxic elements which were above the WHO recommended guidelines for potable water in some dug well and boreholes in Ibadan area.

The high metal concentration in Ibadan area were as a result of Anthropogenic influence such as open air solid waste combustion, saw mills, auto-repair workshops, quarries, gas stations and municipal dumpsites within the surrounding of the study area (Sangodoyin et al ,1992/2008).

Furthermore, Yusuf (a lecturer in Department of Chemistry, University of Lagos) carried out another study in the city of Lagos. Lagos also in southwestern part of the country and it is the most industrialized and populated state in Nigeria. The study was conducted to determine the inorganic quality of the water in the wells and the main sources of the water pollutants in Lagos metropolitan. The outcome of this study showed that majority of the groundwater quality elements were above the World Health Organisation (WHO) recommended guidelines for potable water in regardless of the sources of the pollution. He discovered that total dissolved solid (TDS) is 50% above the limit, pH limit is 44.4% higher, lead (Pb) is 38.9%, Electrical conductivity is 27.8%, sodium(Na2+) and calcium (ca2+) limits are 11.1% above the WHO guidelines.

It was observed from the study carried out in Lagos state that, the main sources of pollution are waste products from various industries, over stressed sewage system and municipal waste dumpsite. Due to high levels of pollutants in these wells because of their closeness to the pollution sources, it was recommended that, the ground water from most of the wells in the areas require further treatment and purification to make it suitable for human usage (Yusuf, 2007).

In addition, there was another study carried out by Taylor et al, 1993 in Uganda, East Africa. The samples were collected from 150 different sites in two catchments in Northern and southwestern Uganda. The samples comprising water from springs and deep boreholes. The sample areas have different climate, bedrocks and topography and each water sample collected was analysed for range of trace metals and major ions.

The results showed that most of the groundwater in these two catchments area is calcium hydro-carbonate in character and are not harmful to human health. Moreover, the concentration of chloride, iron, zinc, aluminium, manganese and total hardness were detected in excess of aesthetic limits set by the World Health Organization. Chromium and Nitrate levels were above WHO regulated standard in eleven (11) different sites in Uganda (Taylor et al, 1993).

Furthermore, trace metals such as Al3+, Cr2-, Fe2+, Mn, and Zn in groundwater were derived from the weathering of the bedrock matrix and corrosion of boreholes rising main. It was discovered that the high concentration of Nitrate arises from proximity to boreholes of sewage waste facilities. The groundwater pollution in Uganda can be controlled by providing adequate and proper attention to borehole locations that could prevent contamination of Nitrate into the groundwater, and regular and frequent maintenance of pipe fixtures can reduce the contamination from corrosion (Taylor et al, 1993).

Subsequently, Lerner et al in 1993 conducted another groundwater analysis in Coventry, United Kingdom. The study reveals that Coventry is underlain by a complex aquifer system consisting of interbedded mudstone and fractured sandstones (Bishop et al 1993). Forty-two (42) water samples were collected for analysis in Coventry and its neighbouring towns such as Kenilworth and Bedworth, which are underlain by permo-carboniferous strata (Lerner et al, 1993). The study revealed that groundwater in Coventry area has been polluted by chlorinated hydrocarbon solvents (CHS). The aim of the study was to determine the origin of CHS pollution, its current and likely potential and future impact and its modes of movement were studied during the groundwater investigation in Coventry area.

Moreover, it was discovered that the main sources of CHS pollution are the industries. The study showed that protection of groundwater would have prevented majority of the pollution occurring, but the main potential problem was unidentified when the compounds were introduced into industrial use. Lerner et al discovered that adequate and proper handling of chemicals is very difficult to achieve in many factories, since the environmental implication of present practices are not identified by the environmental management. It was suggested that new attitude must be instilled in management in order to achieve better groundwater quality in Coventry area (Lerner et al, 1993).

In addition, another analysis on groundwater was carried out by Rojas et al in Lima and Callao, which are both metropolitan cities in Peru. Lima, which is the capital city of Peru with population of 6.5 million as of 1992. The increase in population in this area has led to rapid increase in numbers of people living in an undeveloped and developing settlement near the city of Lima and many of which have no access to safety portable water, electricity and sanitation (Lloyd et al, 1991).

The result of the analysis showed that the problem of groundwater quality in Lima and Callao was linked to the piped distribution network utilizes surface water from the highly populated river Rimac and groundwater from shallow unconsolidated riverine sediments. Few of the contamination were because of mining and agricultural activities, industrial and domestic faecal pollution upstream from the river intake (Bartram et al, 1992).

Furthermore, it was also discovered that aquifer pollution was linked with river Rimac that recharge the aquifer, urban industrial sites, open dug wells in the city of Lima. The contamination of groundwater continues up to the point of consumption and the quality consumed might not necessarily reflect the quality supplied. Lastly, Rojas et al suggested that there should be implemented of effective groundwater monitoring and proper hydrological survey of the Lima aquifer, to implement the flow pattern and immediate and future areas of health risk. The groundwater pollution in Lima can be controlled by effective and adequate monitoring of sewage, industrial and agricultural pollution in Lima and Peru in general (Rojas et al, 1992). However, the pollution case studies in table 5.1 above,  shows that urban areas are characterized by notable percentage of major ion concentration, majority by presence of high metal concentration where industries are present.

The groundwater quality in Offa area falls into this category or general pattern; major ion concentrations were high but not in very significant amount. The degradation of some well groundwater in Offa areas could be because of human activities as well as waste dump disposal in some major places within Offa areas. The comparison of these results illustrated that some of the groundwater sampled were polluted with dissolved solids and trace metals.

5.2     CONCLUSION

The following observation and conclusion were drawn from the study in respect to the results obtained from the data analysis; almost all the pollutants detected in the well water samples analysed were discovered up to 200m away from identified source of pollutions. It was observed that the samples closer to the source of pollution and those within the residential areas consist of toxic elements, cations, anions and heavy metals with higher concentration, but not above the World Health Organisation (WHO) and Federal Environmental Protection Agency (FEPA) Nigeria, stipulated guidelines for potable water.

Subsequently, the results from the data analysis showed that samples collected from well TL6 (Adekunle’s compound) and TL3 (Bale’s compound) are not perfectly clean and pure enough for human consumption, but they required standard treatment even though, no serious casualty or incident has been reported so far as a result of people drinking the water from these wells. However, considering the high concentrations of elements discovered in well TL6 and TL3, it is highly recommended that these wells and some other wells which are very closer to the dumpsite such as TL6 and TL3, (which I was unable to collect the sample due to lack of accessibility or restriction from the owner), should all be properly treated. The water treatment should be carried out in order to prevent unforeseen water-borne diseases such as typhoid, diarrhoea and hepatitis that could lead to serious epidemic disease (Robinson and Cronow, 1992).

In addition, these identified ground water pollutants can be tackled by increasing environmental interventions through public health education, which can be handled by team of well-trained community health workers, also increasing awareness campaigns to improve household and environmental sanitation in rural and urban areas in the developing countries would contribute greatly to combat groundwater pollutant.

Lastly, all the well located within 30m from pollution source should be specially and carefully treated or abandoned, any future or potential wells should be located and constructed beyond 300m from the source of pollution. Modern and standard solid waste disposal technique should be implemented, also provision of modern incinerator should be put into consideration by the government or environmental agency and there should be environmental laws in place to combat the unlawful and improper discharge and disposal of wastes, most especially industrial wastes (Robin,1998). If all these recommended solutions could see the light of the day, there will be great reduction in groundwater pollution and as a result improve the health of people in the Offa area.

WAYS TO EXPAND AND IMPROVE THIS STUDY.

This study can be improved better by using resistivity-sounding method, which is one of the modern methods of investigating the effect of waste dumps on the groundwater, this method will be of great important to improve this study. Moreover, 3D geology software is another advance technology technique, which can be used to design, collate the boreholes and well data in Offa. This will be another great step to improve and expand this study.

However, comprehensive details of the groundwater analysis in Offa area would have produced more detail and better results, provided there was no restriction to some well locations, due to ignorance of some local residents, which led to restriction and unaccessibility to some wells in Offa locality. In order to improve these challenges, there is need for more awareness through publication and campaign so as to enlightening more people in this town of the advantage and benefit which research work can bring into their community.

Furthermore, easy accessibility to recent information and data such as the geological information, copy of annual rainfall, temperature and relative humidity and other vital data or record (of the study area), from the metrological office and other related offices in Ilorin, Nigeria would have contributed greatly to the interpretation of the analysis carried out in the study location.

In addition, another important way to expand and improve this study and research beyond the chemical aspect of the groundwater analysis in Offa area is to investigate and look into the disinfection, microbial aspects, radiological and acceptability aspects of the groundwater in Offa area. Lastly, the study of groundwater investigation can as well be improved, by focusing and expanding the study into other parts of Kwara-State, and possibly to some other major cities in Nigeria and world at large.

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--Temmygold (talk) 19:56, 8 October 2011 (UTC)

IDENTIFICATION OF GEMSTONES USING MACHINE & DEEP LEARNING
IDENTIFICATION OF GEM STONES USING MACHINE AND DEEP LEARNING. Coming from a family of Gemmologist and with a Degree in Geology and Mineral Science, I know how tricky and very difficult it could be to recognised and identify gem stones. For instance even an expert Gemmologist can still find it difficult to differentiate between 170 carat Spinel and Black Prince Ruby shown in the picture below. Naturally, Ruby by mineralogy description is a deep red crystal in colour, very beautiful and hard. And it is very tricky to distinguish even from the close picture from its mineralogical sister (Spinel ),which is also very beautiful but very uncommon like Ruby. Chemically both of them are very similar, except Spinel is containing only one extra ingredient in its molecular mix, even the expert Gemmologist  who have track record in identification of gem stones have often mistaken the spinel for the ruby. In addition, the classic Diamond, with its colourless crystal, also looks so much like the less rare cubic zirconia, that they almost indistinguishable without a close examination. They are isometric {equal-dimensional}, and have stereotypical crystal habits of a octahedron. Diamond is brittle and has a moderate to high specific gravity of 3.5 with perfect octahedral cleavage. Diamond is harder with 10 on Mohr’s scale and It is heavier than water but it is hydrophobic {non-wettable} and will float on water given the right circumstances. Being hydrophobic, diamonds are grease attractive. This property is mostly used to recover many diamonds around the world where extraction tables are coated with grease to extract diamonds. Typically, the grease is a mixture of paraffin and Vaseline in a 1:10 ratio. The specific gravity for diamond is also an additional favourable quality especially for concentration in black sands in stream deposits. This, in combination with the extreme hardness of diamond assures survival over great distances during transportation.

kimberlites are widely known to contained diamond, but Peridotites and Eclogites are the primary host rocks that contain diamond in more quantities. Though both are pieces of the earth’s mantle found as nodules in lamproite, lamprophyre and kimberlite magma.

Furthermore, they were picked up by the magma as it rose through the earth’s upper mantle. A lot of diamond-rich nodules survive intact after being ejected out of the earth’s mantle from depths of 90 to 120 miles, while others disaggregate, and their diamond content is diluted in the magma. It is believed that, the kimberlite magma is a lot poorer in diamond than Eclogites. TRADITIONAL METHOD OF GEM STONE IDENTIFICATION. Hardness: This is one of the most important of all tests, though it’s not usually a definitive way to identify a gem stone, at least it helps in group of possibilities. In gem stone identification, there are a variety of hardness scales that can be used, the most common and widely used is the 'Mohs' Scale' which ranks mineral hardness on a scale of 1(talc) to 10 (diamond). Cleavage : This is the tendency of crystals to break along fixed planes in their structure. By striking the crystalline gem stone, one can examine the break and compare it to various cleavage charts, some of the gem stone usually identified with cleavage are Mica and Quartz Colour: This is a constant and predictable component of the mineral. For instance, Azurite is blue, Cinnabar is red, and Malachite is green (Idiochromatic minerals are "self-coloured" due to their composition). While Allochromatic minerals are "other coloured" due to trace impurities in their composition or defects in their structure. E.g. The beryl family includes gems such as green emerald, pink morganite, and blue to blue-green aquamarine. Streak: is a way of determining the colour of a mineral in powdered form. A specimen of the mineral is placed against a piece of unglazed porcelain plate (called streak plate) and scraped across the surface of the plate. . By comparing the appearance of this streak to various charts, you have another clue to use in gem stone identification. Streak is the colour of a minerals powder when it is crushed. Some minerals have a different colour powder than their actual colour. Every mineral has an inherent streak no matter what colour it is. However, most mineral references don't make a distinction between a white or colourless streak, since the difference is minimal.

Lustre: is the way light interacts with the surface of a crystal, rock, or mineral However as explained earlier Diamond with its colourless crystal, looks so much like the cubic zirconia, that they almost indistinguishable without a close examination.

Chemical and Physical tests: These methods of identification of gems most often used by experts because they usually require special equipment. The tests include: • Specific gravity. • Refractive Index. • Light Dispersion. • Colour changes.

GEM STONES SORTER: MACHINE LEARNING.

Due to the complexity and increasingly difficult to visually distinguish the gems processed by modern technology; therefore, we find it interesting, by conducting and starting a research using a variety of analytical methods in machine learning and deep learning with initial testing and analysis using methods, such as infrared and Raman spectroscopy. A high performance confocal Raman microscope to perform non-destructive identification and characterisation of gemstones, such as diamond, Ruby, Jade and other gem stones.

Furthermore, experimenting a machine learning model with Spectrometers gives a very convincing 96.9 % certify gem authenticity and it determines whether gems are natural, synthetic or treated. An important advantage is the ability to perform non-destructive analysis of gemstones. Similar analysis had been conducted in Beijing, Shanghai and Shenzhen using Renishaw Raman spectrometers.

The machine-learning algorithm was used to identify gem streak, Light Dispersion, colours, specific gravity and Refractive index.

One of the challenges encountered includes Training this not only had to learn which of the identification properties represented genuine gemstone of interest and which indicated synthetic or fake based on the objective. The algorithm also needed to learn which properties produces incorrect and insubstantial predictions and might eventually be ignored completely or removed from the features for better predictions. However, the prediction can also be improved by adding more properties, this was found to be possible to increase the false-positive prediction rate to 97.9% when training the algorithms and the machine. Though there’s plenty of room for improvement.

The software calibration for the machine learning can also be daunting technically. Python programming language was used for the machine learning algorithm, making use of the necessary libraries. Sapera LT SDK and ACQ4 were used for frame buffering, camera integration and communication while Open CV was used for processing of images.

Subsequently, Deep learning using ANN was deployed for learning and training the vital properties and then conduct the grouping and classification of the gem stones while the prediction is consistently triggered at a very precise time.

There is huge suggestion to add many more Gem stones and in the future, create a simple autonomous AI equipment that would be able to carry out the Gem stones and minerals identification and recognition accurately. References

1.Alberto Scarani, and M&A Gemmological Instruments. “GemmoRaman-532.” MAGI – M&A Gemmological Instruments. N.p., n.d. Web. 27 July 2016. 2.Ye. Jian, “Laser Raman Spectrometry: Advanced Weapons for Gemstone Identification. July,2016. 3.R. Espinosa-Luna, and Claudio Frausto-Reyes. “Optical characterization of amber of Chiapas.” Revista mexicana de física 60.3 (2014): 217-221. 4.H. Calvo, Jose Luis Ruvalcaba, and Tomás Calderón. “Some new trends in the ionoluminescence of minerals.” Analytical and bioanalytical chemistry 387.3 (2007): 869-878. --Temmygold (talk) 12:32, 11 January 2018 (UTC)

Temidola Ojelabi (MSc.) E-mail: temmymitchell@yahoo.com Principal Data Scientist Consultant.

25 Powerful ways of creating great insights from a Big Data.
Over the years, the biggest problem I see in many organizations is the believe and assumption that having a big data like Mount Everest and streams of data like Pacific Ocean, will automatically reveal the hidden diamond in the data. They think if they can figure out how to manipulate the data in just the right ways, or use the latest and sophisticated big data tool or service, then actionable insights will just begin to pop up like story a from fairytale.

Subsequently, another big challenge is the inability to break down the bureaucracy in some organisation, in such organisation, they can have an experienced expert IT team, they can have team of dexterous marketers worthy of their own TV show on their payroll, they can even afford the most talented Data analyst or even one of the finest analytics partner in the world, but if there is lack of effective communication among these stakeholders, no matter how big the data and the actionable insights could be, all your efforts can be in vain and useless.

The best strategy to get insights comes before the data collection, tool selection, or analysis. The good approach is to ask the right questions.

Exploratory analysis is important, but trying to get insights that way is like going to the car dealer without a particular car in mind. You end up admiring all the cars. If you have a focused, business-critical question that needs to be answered, then that informs the data collection, analysis and visualization that will reveal the most important insights

Furthermore, the journey from data to business growth starts with a healthy organization, founded on effective communication and not confrontation, a business constantly inspired, motivated, and curious about data, the possibilities and opportunities it would bring across the entire organization.

Lastly, different people can interpret the same data differently. It all depends upon the context in which they analyse and interpret the data. The one who has got superior understanding of context, will interpret the data more accurately.

In this article, I will discuss 25 great ways of creating good insights from a data based on my experience and other great professionals we’ve done some great and fascinating Data science projects together.

25 powerful tips of creating great insights from a Big data

1.	Data itself is completely acquiescent. It doesn’t tell you anything until you ask a question and then seek the answer in your data. I suggest asking questions that focus on uncovering the behavioural intent of users. Formulate a hypothesis.

2.	One approach to turn data into actionable insights is to ask yourself what you are really looking for. If you don’t have a clearly defined and specific question you certainly won’t get a clear answer either.

3.	It is crucial that your data and insights are relatable. Many Data analysts are unable to drive action, because they couldn’t tie their findings to business impact. The easiest path for most analysts to actionable insights is through a solid optimization program they can plug into.

4.	Good analyst should start with the Why, then, you should align the process to the organisation’s most important outcomes, and must not getting distracted investigating tangents and disappearing down rabbit holes. 5.	To push all investments in people, tools and processes in the right direction there is a need for a good analytics program with a solid Key Performance Indicator framework. A good KPI framework gives an overview of what the organization is trying to achieve and ties that to how it would be measured. And most importantly there’s a need for continual dialogue between data analyst and management.

6.	Generating good insights requires an understanding of your business and its products, your website content, its engagement points and processes, your value proposition, and of course its marketing plan.

7.	Building a quantification strategy to capture the data is vital, then treat it as your analytics roadmap through the entire project. That way once it’s time to run your analysis you’ll have a blueprint for where to start and have the confidence to know that you already have good, clean data to base your hypothesis on.

8.	Another great way to create a great insight from data is by Starting with a hypothesis and a willingness to change if the data validates your hypothesis. Start the analysis when you are looking for something to change or improve, then segment by as many different dimensions as possible.

9.	Keep in mind that, the answer to your question may not be something that you expected. Be curious and open. But be clear about whether you’ll be making a UI change, make change to a copy, running an A/B test, marketing campaign adjustment, etc based on the question.

10.	Carefully choose your metrics wisely, make sure that they connect with the goals of your organization and educate everyone working with the data how these metrics add up and contribute to the main KPI.

11.	It is important to be very clear about how specific metrics being tracked contribute to one or more business goals of the organization, If these connections to desired outcomes aren’t clear to all involved, or aren’t directly enough, then the movements in the data would have less meaning and these metrics will end up contributing to ‘analytics overload’.

12.	Most organizations that are achieving positive impacts are those that put data-driven, customer-focused problem solvers behind all digital transformation initiatives. In so many industries, processes and consistency are what keeps the lights on.

13.	It is advisable not to be obsessed or focused on any one particular metric. While each individual metric has the potential to provide important insights and direction for strategic decisions, it is only when you understand the overall pattern of responses that you obtain the deepest and most important insights.

14.	One of the most important key is to build a culture that sees data as the epicentre for their digital strategy. Without this it is very difficult to consistently prioritize the value of data analysis to build actionable insights. To build this data-driven culture it requires; hiring the right talent who can decipher data and are passionate advocates.

15.	Focus on developing a keen intuition of your stakeholder’s aspirations and challenges. Learn to visualize the data in a way that promotes cognition, not confusion. Clearly articulating your specific data story with underlying questions of what, how and why behind it. And finally, extending your added value by attaching recommendations that are aligned with the data story, assigned to a specific owner, and time-bound for accountability.

16.	A perfect way to ensure your data is collected properly is to apply data   quality processes for digital analytics quality and automate data verification as much as possible.

17.	It’s indispensable to understand your audience. All the other aspects of your data from acquisition, to conversions, to behaviour; all revolve around the users, and how you can segment based on your specific audiences

18.	Good actionable insight = good understanding of the business questions + good, rational and reliable data set + good data visualization + good story to back it up.

19.	During analysis stage, learn to focus on trends, not data itself. The best insight comes from looking at trends especially when they change direction and compare time ranges and It is helpful to search for strong relationships between variables or correlations.

20.	Break complex ones into pieces, start with small actions, and proceed with them sequentially. Make sure that the insights are aligned with the business requirements and primary KPIs of the decision makers.

21.	Understand that great sites aren’t great because they make loads of money, great sites make loads of money because they are great. Users are the judge of the greatness of your site, so your data is your users telling you how to make your site better for them. Embrace these insights, deliver for your users first and business success will follow and not any other way around.

22.	You need to set an underlying digital goals framework from your organisations objectives. Then you can focus your time and effort on dimensions and metrics that really count.

23.	Make it interesting and not boring, so next time you’re creating a report full of tables and pie charts, think a little harder and try building clear visualizations that communicate the data in a more understandable and interesting way. Data is more meaningful when your audience see fun in your delivery.

24.	The two main ways analytics can drive value are performance measurement and hypothesis validation, and those are two fundamentally different things. Performance measurement is where dashboards live, and it’s all about the past. It should be KPI-driven, objective, automated, clear, and concise, while hypothesis validation, on the other hand, is about the future.

25.	Finally, design and create a unified place for easy integration of traditional databases and big data which can be monitored, and this can help to control the collection (integration), management (data quality), Analysis (data exploration), and Data solutions (automation) which are the fundamental pipeline for a creating good insights.

Temidola Ojelabi (MSc.) Principal Data Scientist Consultant.

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CNMall41 (talk) 06:15, 15 March 2019 (UTC)

Draft:Temidola Ojelabi


Hello, Temmygold. It has been over six months since you last edited the Articles for Creation submission or draft page you started, Draft:Temidola Ojelabi.

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