Basement and crystalline basement rock are used to define the rocks below a sedimentary platform or cover, or more generally any rock below sedimentary rocks or sedimentary basins that are metamorphic or igneous in origin. In the same way the sediments and/or sedimentary rocks on top of the basement can be called a cover or sedimentary cover. The basement complex may as known consists of various rock types including granites, granodiorites, charnockites, syenites, gneisses,migmatites, blastomylonites, marbles, quartzite’s, schist’s etc. All these rocks as expected exhibit various mineralogical compositions, textures andstructures. The basement generally refers to rocks older than the Variscan orogeny. Geochronology is the science of determining the age of rocks, fossils, and sediments, within a certain degree of uncertainty inherent to the method used. In review of this, the geochronological study of the crystaline basement will have to deal with the time study of all this basement rocks, therefore it will anable geologist to be able to determine how old rocks that are situated in the basement complex. A variety of dating methods are used by geologists to achieve this, and schemes of classification and terminology have been proposed.The approach of using several methods is preferred for best results Nigeria and its Environs
The Federal Republic of Nigeria, is a federal constitutional republic and its Federal Capital Territory is situated in Abuja. The country is located in West Africa and shares land borders with the Republic of Benin in the west, Chad and Cameroon in the east, and Niger in the north. The three largest and most influential ethnic groups in Nigeria are the Hausa, Igbo and Yoruba. In terms of religion Nigeria is roughly split into half and half between Muslims in the North and Christians in the South,a very small minority practice traditional religion 1.1.1Location (Coordinates)
Nigeria lies very close to the equator in west coast of Africa between latitude 4 N and 14 N degree and longitude 2 E and 15 E degree. The country is located at the Northern end of Eastern branch of west coast of Africa rift system. Nigeria geological set up comprises broadly sedimentary formation and crystalline basement complex, which occur more or less in equal proportion all over the country. The sediment is mainly Upper Cretaceous to recent in age while the basement complex rocks are thought to be Precambrian. The studied area lies between latitude 12.4" and 11.11"W and longitude 13.81" and 14.13" S.
The topography of Nigeria consists of plains in the north and south interrupted by plateaus and hills in the centre of the country. The Sokoto Plains lie in the northwestern corner of the country, while the Borno Plains in the northeastern corner extend as far as the Lake Chad basin. The Lake Chad basin and the coastalareas, including the Niger River delta and the western parts of the Sokoto region in the far northwest, are underlain by soft, geologically young sedimentary rocks. Gently undulating plains, which become waterloggedduring the rainy season, are found in these
Climate for the area of study is the typical tropical climate of averagely high temperatures, its enjoys the humid tropical climate type. Because of its location just north of the equator, also enjoys a truly tropical climate characterised by the hot and wet conditions associated with the movement of the Inter-Tropical Convergence Zone north and south of the equator. It also experiences consistently high temperatures all year round. Since temperature varies only slightly, rainfall distribution, over space and time
1.1.4Basic rock types in the area
The three major rock types - igneous, meta- morphic and sedimentary - abound in Nigeria. Igneous and metamorphic rocks constitute the Pre- cambrian basement complex which is the oldest, crystalline, solid physical foundation of the...