The Geo-statistical evaluation of the hydrochemical data of river Niger floodplain water in Jebba and its environs, Nigeria was carried out using Multivariate statistical analysis such as Correlation Analysis (CA), Factor Analysis (FA), Hierarchical Cluster Analysis (HCA) and Principal Components Analysis (PCA) to classify the water geochemistry. Inductively Coupled Plasma Spectrometry technique was used for cations analysis while the anions were analyzed by using volumetric analysis. The water samples were characterized for the physicochemical parameters such as temperature, electrical conductivity, pH, and Total dissolve solid (TDS) through the use of thermometer, conductivity meter, TDS meter pH meter for in-situ measurement. Twenty-four representative samples were selected randomly showing relative abundance of cation and anion concentrations as follows Na++ K+ >Ca2+ > Mg2+ and HCO3- + CO32-> Cl- > SO42- respectively. Trace elements show an increasing order Fe>Al>Mn>Pb>Zn>Ni>Cu with Fe, Pb, Mn and Al concentrations (19.02, 0.17, 1.072 & 3.07) respectively exceeding the WHO (2012) standard in some of the water samples analyzed which is due to anthropogenic sources from the area. The hydrochemical facies of the study area is characterized by Na++K+-HCO3-, Na+-K+-Cl--SO42-, Ca2+-Mg2+-HCO3- water types. According to Kelly’s ratio and Wilcox diagram suggested that the water is good for Irrigation purpose. Gibbs diagrams show that the source of ions in the water is from rock and precipitation dominance. Correlation matrix shows that most of chemical parameters of the water have very high, high and moderate correlation. The factor obtained from Factor analysis indicated and support the Gibb’s diagram that the parameters responsible for water quality variations are mainly related to water-rock interaction (particularly weathering of silicate minerals) and anthropogenic sources. Four clusters generated from clusters analysis indicate fresh water type and interpreted as rock-water interaction.
Also, Petrographical analysis of the rock samples analyzed were in accordance and supported Gibbs diagram which shows one of the major sources of ions in water is from rock dominance which is due to the weathering of the minerals such as silicate minerals, amphibole, biotite, plagioclase, microcline present in these rocks.
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TABLE OF CONTENTS
TITLE PAGE
CERTIFICATION…………………………………………………………...…………..ii
DEDICATION…………………………………………………………………………..iii
ACKNOWLEDGEMENT……………………………………………………………...iv
TABLE OF CONTENTS……………………….……….………………………………v
LIST OF FIGURES……………………………………..………………………………ix
LIST OF TABLES……………………………………...………………………………xii
ABSTRACT…………………………………………….………………………………xiv
CHAPTER ONE: INTRODUCTION…………………………………………………..1
1.1 GENERAL STATEMENT .................................................................................. 1
1.2 SCIENTIFIC BACKGROUND ................................................................................ 2
1.2 SIGNIFICANT OF GEOSTATISTICS ............................................................. 13
1.3 LOCATION OF THE AREA ............................................................................. 14
1.5 CLIMATE AND VEGETATION ........................................................................... 16
1.6 DRAINAGE ............................................................................................................ 16
1.7 HUMAN SETTLEMENT AND OCCUPATIONAL ACTIVITIES ...................... 18
1.8 PREVIOUS WORK DONE .................................................................................... 18
1.9 STATEMENT OF PROBLEM ............................................................................... 24
1.10 AIM AND OBJECTIVES ..................................................................................... 25
1.11 SCOPE OF STUDY .............................................................................................. 25
CHAPTER TWO: GEOLOGICAL AND HYDROLOGICAL SETTINGS…...…...27
2.1 GEOLOGY OF NIGERIA ...................................................................................... 27
2.2 LOCAL GEOLOGY OF THE STUDY AREA ...................................................... 30
2.3.1 QUARTZITE .................................................................................................... 30
2.3.2 SCHISTS .......................................................................................................... 32
2.3.3 GRANITE GNEISS .......................................................................................... 32
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2.3.4 PORPHYRITIC GRANITE ............................................................................. 32
2.3 HYDROGEOLOGY ............................................................................................... 33
2.4 WATER POLLUTION ........................................................................................... 33
2.4.1 SOURCES OF WATER POLLUTION ........................................................... 33
2.4.2 EFFECT OF WATER POLLUTION ............................................................... 34
2.4.3 MEASUREMENT OF WATER POLLUTION ............................................... 34
2.5 WATER QUALITY ................................................................................................ 35
CHAPTER THREE: METHODOLOGY……………………………..…………...…39
3.1 GENERAL STATEMENT ..................................................................................... 39
3.2 MATERIALS AND METHODS (SAMPLING AND SAMPLE TREATMENTS)
....................................................................................................................................... 39
3.2.1 WATER SAMPLE ........................................................................................... 39
3.2.2 ROCK SAMPLE .............................................................................................. 39
3.3 SAMPLING MATERIALS AND REAGENT USED ON THE FIELD ................ 40
3.4 FIELD PROCEDURES AND STORAGE ............................................................. 42
3.4.1 SAMPLING METHOD AND STORAGE....................................................... 42
3.5 MEASUREMENT OF PHYSIOCHEMICAL PARAMETERS............................. 42
3.5.1 TOTAL DISSOLVED SOLIDS (TDS) ............................................................ 42
3.5.2 ELECTRICAL CONDUCTIVITY (EC) .......................................................... 43
3.5.3 PH ..................................................................................................................... 43
3.5.4 TEMPERATURE ............................................................................................. 44
3.6 PHYSIOCHEMICAL EVALUATION................................................................... 44
3.6.1 MAJOR CATIONS AND ANIONS ................................................................. 44
3.7 SOURCES OF IONS/METALS IN WATER ......................................................... 47
3.7.1 INDICES OF BASE EXCHANGE .................................................................. 47
3.7.2 GIBBS .............................................................................................................. 48
3.8 ASSESSMENT OF CONTAMINATION .............................................................. 48
3.8.1 CONTAMINATION FACTOR ....................................................................... 48
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3.8.2 GEO-ACCUMULATION INDEX ................................................................... 49
3.8.3 ENRICHMENT FACTOR ............................................................................... 50
3.9 HYDROCHEMICAL METHODS ......................................................................... 51
3.9.1 PIPER’S DIAGRAM ........................................................................................ 51
3.9.2 STIFF’S DIAGRAM ........................................................................................ 51
3.9.3 DUROV’S DIAGRAM .................................................................................... 51
3.9.4 SCHOLLER’S DIAGRAM .............................................................................. 52
3.9.5 KELLEY’S RATIO .......................................................................................... 52
3.9.6 WILCOX DIAGRAM ...................................................................................... 52
3.10 STATISTICAL EVALUATION OF FLOODPLAIN WATER ........................... 52
3.10.1 CORRELATION ANALYSIS (CA) .............................................................. 52
3.10.2 FACTOR ANALYSIS (FA) ........................................................................... 55
3.10.3 PRINCIPAL COMPONENT ANALYSIS (PCA) ......................................... 55
3.10.4 HIERARCHICAL CLUSTER ANALYSIS (HCA) ....................................... 55
CHAPTER FOUR: PETROGRAPHICAL CHARACTERISTICS OF
CRYSTALLINE ROCKS IN THE STUDY AREA………………………………….57
4.1 GENERAL STATEMENT ..................................................................................... 57
4.2 PETROGRAPHICAL ANALYSIS OF ROCK SAMPLES ................................... 57
4.2.1 GRANITE ......................................................................................................... 57
4.2.2 GRANITE-GNEISS ......................................................................................... 63
CHAPTER FIVE: PRESENTATION AND INTERPRETATION OF
HYDROGEOCHEMICAL DATA…………………………………………...………..66
5.1 GENERAL STATEMENT ..................................................................................... 66
5.2 RESULTS OF PHYSICO-CHEMICAL PARAMETERS AND
INTERPRETATION ..................................................................................................... 66
5.3 MAJOR IONS AND INTERPRETATION ............................................................ 74
5.4 HYDROCHEMICAL FACIES AND INTERPRETATIONS ................................ 85
5.4.1 PIPER’S GROUNDWATER CLASSIFICATION .......................................... 85
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5.4.2 DUROV DIAGRAM ........................................................................................ 88
5.4.3 STIFF DIAGRAM ............................................................................................ 90
5.4.4 SCHEOLLER’S DIAGRAM ........................................................................... 97
5.5 AGRICULTURAL PURPOSE ............................................................................. 100
5.5.1 KELLEY’S RATIO ........................................................................................ 100
5.5.2 WILCOX DIAGRAM .................................................................................... 102
5.6 TRACE ELEMENTS ............................................................................................ 104
5.7 SOURCES OF IONS/METALS IN WATER ....................................................... 111
5.7.1 INDICES OF BASE EXCHANGE ................................................................ 111
5.7.2 GIBBS RATIO ............................................................................................... 113
5.8 ASSESSMENT OF CONTAMINATION ............................................................ 118
5.8.1 CONTAMINATION FACTOR (CF) ............................................................. 118
5.8.2DEGREE OF CONTAMINATION ................................................................ 121
5.8.3 GEO-ACCUMULATION INDEX ................................................................. 123
5.8.4 ENRICHMENT FACTOR (EF) ..................................................................... 125
5.9.1 CORRELATION ANALYSIS ....................................................................... 127
5.9.2 HIERARCHICAL CLUSTER ANALYSIS ................................................... 130
5.9.3 FACTOR ANALYSIS .................................................................................... 139
5.9.4 PRINCIPAL COMPONENT ANALYSIS ..................................................... 143
CHAPTER SIX: SUMMARY, CONCLUSION AND RECOMMENDATION…..148
6.1 SUMMARY .......................................................................................................... 148
6.2 CONCLUSION ..................................................................................................... 149
6.3 RECOMMENDATION ........................................................................................ 152
REFERENCES…………………………………………...……………………………153
