ABSTRACT
This Study investigated the Geology of the area which was achieved through detailed Geological Mapping and various Laboratory Analysis. The Geological Mapping done in the area shows Nanka Formation and Ogwashi-Asaba Formation are the dorminant sedimentary Formations of the area.
The study area Azia and Environs is located between Longitudes 06° 53′ 00″E to 06° 57′ 00″E and Latitude 005° 51′ 30″N to 005° 55′ 30″N in the South-Eastern part of Nigeria.
The Laboratory test shows that the clay of Ogwashi-Asaba Formation has low to high plasticity and this makes it unsuitable for engineering purpose such as land filling. The water analysis of the stream samples in the study area reveals concentration in the value of magnesium which ranges from 25 to 40 which is above WHO standard permissible. Therefore, pre-treatment of the water before consumption is recommended for health reasons. The study area is naturally endowed with economic deposits like laterite, sand, shale, ironstone, and kaolin. The occurrence and prevalence of erosion is attributed to the combination of several factors like Geology, Topography and Human activities.
CHAPTER ONE
INTRODUCTION
- Location and Accessibility of the study area (Azia and environs)
The study area covers an aerial extent of approximately 154km2, extending through Ukpor, Azia and Orsumoghu all within Anambra State in south Eastern Nigeria. It is within Latitudes 0050 51. 30I N to 0050 55.30I N and Longitudes 060 53.00I E to 060 57.00I E.
The main accessibility to the area is by Road, the area has good road network that includes; Nnewi-Ekwulimili Road, Onitsha-Owerri Express Road, Azia-Lilu Road, Other roads are untarred Ukpor-Okija road, Ukpor-Ozubulu road as well as through tracks and footpaths that link the streets within the community.
1.2 Aim of the Study
The aim of this project work is to carry out a geological investigation of Azia and environs,
Southeastern Nigeria. The objectives include:
- To carry out geological field mapping of the study area and subsequently produce a geologic map.
- To identify the Geologic structures of the study area.
- To identify the Economic geological potentials of the study area.
- To equally study the Environmental geology and to do hydrochemical water analysis of the study area.
Fig 1.1 Accessibility Map of the study area
1.3 Geomorphology
A branch of Geology that studies the formation and structural features of the earth’s surface. This includes topography and drainage. These processes are mainly controlled by the physiography of the area.
1.3.1 Physiography
Description of the earth’s physical structures. The physiography of the study area will be based on climate, temperature, rainfall and vegetation.
1.3.2 Topography
The study area is relatively undulating with Nanka sand and ogwashi-Asaba formation with an outcrop of clay(kaolin). Outcrops of the clay were observed along various river and gully erosion channels, road cuts and erosional surfaces at various locations.
Significant control of topography on distribution of clay mineral has been reported. The clay is commonly interbedded between lateritic mantle and sandy materials at a variable depth of 0-4m (Akudinobi,2006).
Fig 1.2 Topographic map of the study area
1.3.3 Drainage Pattern
The drainage of the study area is dendritic and trellis type of drainage.It is made up of minor Rivers all draining into River ulasi at some point. River Orashi is the major river in the area of study and it drains into River Niger.
Thus can serve for Inland River transport if well dredged. The volume of water in the rivers are controlled by seasonal changes of the year (wet and dry seasons).
Plate 1.1 Ulasi River, one of the River that drains the study area
Fig 1.3 Drainage map of the study area
1.4 Climate and Vegetation
Climate is the prevailing atmospheric condition of a particular area over a long period of time and I can say that the area of study experiences two weather seasons yearly, namely; wet and dry seasons. The wet season starts from April and ends in October while the dry season starts from November and ends in February.
The vegetation of the study area ranges from light rainforest to savannah and is mainly controlled by the geologic factors, relief, lithology and other factors. Dense vegetation cover, with high trees is prominent around streams in the study area. The soft rocks that underlie these areas support the growth of luxuriant trees. This vegetation is dominated by grassland though some plant species of lowland rainforest such as palm trees are present which is due to the abundant rainfall in this part.
The trees in this area shed their leaves in the dry season which help to reduce the loss of water by transpiration in plants.
Fig 1.4 :Geologic Map of the Study Area(Azia and its Environs)
