CHAPTER ONE
1.0 INTRODUCTION
Clay is a common name for a number of fine grained earthly materials that become plastic and tenacious when moist, and that becomes permanently hard when baked or fired. According to (Velde, 1995), clay is applied to materials having a particle size less than 2 micrometers and to the family of minerals that has similar chemical composition and common crystal structural characteristics.
Clay is formed either as a product of the chemical weathering of pre-existing granitic rock and feldspar minerals particularly in warm tropical and subtropical regions of the world or as a result of the hydrothermal alteration of granitic rocks. Chemically clays are hydrous aluminum silicate, ordinarily containing impurities, for example potassium, sodium, calcium, magnesium, or iron in small amounts and are characterized by sheet silicate structures of composite layers stacked along the c-axis (Grim 1968).
Clay has wide characteristics of physical characteristics such as plasticity, shrinkage under firing and under drying, fineness of grain, colour after drying, hardness, cohesion and capacity of the surface to take decoration.
Clay and clay minerals have been mined sine stone age and have been indispensable in architecture in industry and agriculture.
1.1 AIMS AND OBJECTIVES OF THE STUDY
1. To investigate the physio-chemical properties of clay through laboratory analysis.
2. To understand the mineralogy of clay through laboratory analysis.
3. To investigate their possible industrial applications.
1.2 LOCATION OF STUDY AREA
The study area is located between the latitude 50 11 54.311 (5.03180) north of the equator and longitude 60 241 1.211(6.40030) east of the Greenwich meridian. The area of study is located in Yenegoa local Government area of Bayelsa state in the Niger Delta of Nigeria.
1.3 ACCESSIBILITY OF THE STUDY AREA
Igbogene is situated between Akiogbologbo and Yenegoa and is also nearby to Yenegwe. The study area is 4km south east from Yenegwe Akiobologbo, 5km west from Yenegoa, 5km southwest from Akenfa 5km east from Odieke, 5km east from Agbo and 6km northwest from Agbia.
1.4 CLIMATE OF THE STUDY AREA
The climate of Igbogene is tropical. Like other parts of Nigeria, the area is known to have two seasons, the wet season (rainy season) which begins from March until October and the dry season which begins from November to early parts of March. The average annual temperature is 26.70C and the average rainfall is 2899 mm.
1.5 VEGETATION OF THE STUDY AREA
Igbogene is surrounded by a tropical rain forest to the southern part of Nigeria. The long period of rainfall ensures an adequate supply of water, flooding and also continuous presence of moisture in the air and soil promote growth of every green plant and trees even in dry season. Different types of plants can be found in the area, such as cassava, vegetable sugarcane, water yam, etc. the grasses grow in open parches. The vegetation pattern gives an idea about the soil formation.
1.6 RELIEF AND DRAINAGE
The study area is generally a lowland plain about sea level. The land surface slopes gently in the north-south direction.
1.6.1 DRAINAGE
The study area is drained by a major river (nun) and creeks which source is the river Niger, the river flows from the north-west to the south-east direction.
1.7 GEOMORPHOLOGY AND GEOMORPHIC UNITS
The geomorphology of the Niger delta is derived mainly from the works of Allen (1946 and 1965) Reyment (1965).
The Niger delta has an essential flat topography and slopes very slightly towards the coast. The area is flat with an elevation exceeding 35m above sea level.
Akpokodje (2001) distinguished (5) geomorphic unit in the Niger Delta are:
1. Dry flat land and plains
2. Fresh water swamps
3. Meander bets and alluvial swamp
4. Salt water or mangrove swamp and active abandoned coastal ridges
5. Sombreiro-wari deffaic plain with abundant of fresh water beach swamp.
