Subsurface Layer Characterisation Research

Subsurface Layer Characterisation Research SUBSURFACE LAYER CHARACTERISATION FOR ENGINEERING PURPOSES USING VERTICAL ELECTRICAL SOUNDING IN BANANA ISLAND, LAGOS, NIGERIA OLADUNJOYE, H.T., 2OLALEYE, A.O. Conceptual Seven (7) vertical electrical sounding stations along two navigates were utilized to consider the profundity to skillful development for establishment of designing structures in Banana Island of Lagos. The examination is intended to disentangle the nearness of issue soils that can be unfriendly to structures.  The sounding information utilized in this examination was procured utilizing Schlumberger Electrode Configuration. The VES information were deciphered into a model bend utilizing forward demonstrating programming called Winglink. The translation boundaries (layer resistivities and thicknesses) for each VES point were gathered into three geo-electric segments to speak to the 2-D models of the subsurface layers in the investigation territory. The last understanding outcomes (resistivities and profundities) demonstrated as geoelectrical areas and pseudosections were analyzed inside the overviewed zone and corresponded with the borehole log-inferred profundities to decide a likely profundity for establishments of tall structure. The examination inferred that the geophysical examination is of extraordinary noteworthiness in halfway bend coordinating translation procedure gives the most reliably low rate deviation blunder edges among the three VES primer understanding methods. There is reliable increment inside and out expectation blunder, with profundity, in all the translation procedures. Presentation Geophysical resistivity procedures depend on the reaction of the earth to the progression of electrical flow. In all techniques, an electrical flow is gone through the ground and the subsequent potential cathodes permit us to record the resultant expected contrast between the flow terminal is estimated. The evident resistivity is then a component of the deliberate impedance (proportion of potential to current) and the geometry of the anode cluster. Contingent on the review geometry, the obvious resistivity information are plotted as 1-D soundings, 1-D profiles, or in 2-D cross-areas so as to search for irregular locales. In the shallow subsurface, the nearness of water controls a great part of the conductivity variety. Estimation of resistivity (reverse of conductivity) is, all in all, a proportion of water immersion and network of pore space. This is on the grounds that water has a low resistivity and electric flow will follow the easiest course of action. Expanding immersion, expanding saltiness of the underground water, expanding porosity of rock (water-filled voids) and expanding number of cracks (water-filled) all will in general decline estimated resistivity. Resistivity estimations are related with fluctuating profundities relying upon the detachment of the present and expected terminals in the study, and can be deciphered as far as a lithologic and additionally geohydrologic model of the subsurface. The decision for Direct Current (DC) resistivity overview in this undertaking is because of its capacity to give a fast concise picture of lithological and groundwater qualities as far as its clear resistivity differentiate. In this work the electrical resistivity character gathered were model with Winresist and Winglink reversal programming. The layers boundaries (resistivities and thicknesses) acquired from information handling were then modified with Winglink to give two-dimensional pictures of the subsurface clear resistivity variety (Pseudosection). In any case, information on the geography of the region from gained borehole log has assumed an essential job in deciding the best fit model. MATERIALS AND METHOD OF STUDY The vertical electrical resistivity is utilized to decide the subsurface resistivity dispersion and profundity of the sub-surface layers with the guide of electrical resistivity meter. In this examination, Schlumberger exhibit of electrical resistivity technique was embraced due to the minimal effort of the field activity, decreased coordinations labor and furthermore quicker. A sum of Six (6) vertical electrical sounding (VES) were estimated inside the territory. The resistivity estimation is taken by presenting little bit of power through two current anodes (An and B) and estimating the resultant voltage drop between a couple of likely cathodes (M and N). A basic determined estimation of clear resistivity is the boundary bearing the data for the attributes of the earth (Tonkov, 2008). From the establishment of electrical resistivity hypothesis is the ohms law (Grant and West, 1965; Dobrin and Sarvit, 1988):    â â â â â â â â (1) Where Ï  is the resistivity, R is the opposition, L is the length of the leading chamber and An is the cross sectional territory. For the strong earth, whose material is overwhelmingly comprised of silicates and fundamentally non conveyors, the nearness of water in the pore space of the dirt and in the stones cracks upgrades the conductivity of the earth when an electrical momentum I is gone through it, subsequently making the stones a semi conductor.â Since the earth isn't care for a straight wire and it's anything but an anisotropic, at that point Equation 1 can be redone as:  â â â â â â â â â â â â â â â â â â â â (2) Where change in voltage and r is the sweep of current cathodes side of the equator. Since the earth isn't homogeneous, Equation 2 is utilized to characterize an evident resistivity which is registered as the result of the geometric factor and the opposition recorded in the electrical resistivity meter and resistivity the earth would have in the event that it were homogeneous (Grant and West, 1965;):  â â â  â â  â â â â â â â â â (3) Where, 2ï€r is then characterize as the geometric factor (G) fixed for a given cathode setup and is reliant on the terminal course of action. The Schlumberger anode arrangement was utilized for this examination. The geometric factor is in this manner given as:  â â (4) Where AB is the separation between two current cathodes, MN is the separation between two expected terminals. Area AND GEOLOGY OF THE STUDY AREA The investigation territory is situated in the south-eastern piece of Lagos State between Latitudes 6â ° 25 to 6â ° 28 North of the Equator and Longitudes 3â ° 24 to 3â ° 30 East of the Greenwich Meridian (Fig.1.1). The examination region Lekki and its environ issituated inside the western Nigeria waterfront brooks and tidal pond created by obstruction sea shores related with sand affidavit (Pugh, 1954). It frames some portion of the Lagos tidal pond framework known as the biggest of the four tidal pond framework in the bay of guinea coast (Adepelumi and Olorunfemi, 2000). Banana Island is a fake island in Lagos State, Nigeria. It is situated in the Lagos Lagoon and joined toward the North-Eastern Ikoyi Island by a devoted street strip which is connected to the current street organize. The banana-formed Island is roughly 1,630,000 square meters in size (not exactly a square mile) and is isolated into 536 plots (of somewhere in the range of 1000 and 4000 square meters in size) primarily organized along circular drives, so intended to upgrade the generally private nature of Ikoyi. Banana Island is a fake island recovered from bits of the Lagos Lagoon, topographic rise got at the site found the middle value of 4 meters above mean ocean level. The examination region is situated inside the beach front locale of Nigeria with an atmosphere of long wet season (April to October) and short dry season (November to March). Normal yearly precipitation is above 2000mm and fills in as a wellspring of groundwater energize. The zone is helpless to flooding after substantial precipitation during the wet season. Nigeria lies in a broad Pan-African versatile belt which isolates the West African and Congo Cratons. The belt is deciphered to have developed from the mainland crash between the West African craton and the Pan-African belt (Black et al., 1979; Caby et al., 1981). Geochronologically, the Precambrian rocks of Nigeria can be assembled into four significant classes (Liberian Orogeny 2800  ± 200 Ma, Eburnean Orogeny 2000  ± 200 Ma, Kibaran Orogeny 1100  ± 200 Ma and The Pan-African Orogeny 600  ± 150 Ma). These classes relate with the four orogenic occasions that have punctuated the Precambrian history of Africa (Odeyemi, 1979). Figure 2.1: Regional Geological Map of Nigeria (Modified after Ajibade et al., 1988) Seaside Nigeria involves two sedimentary bowls: The Benin-Dahomey bowl and the Niger Delta bowl isolated by the Okitipupa edge. The stones of the Benin bowl are primarily sands and shales with some limestone which thicken towards the west and the coast just as down plunges to the coast. Ongoing dregs are underlain by the Coastal Plains Sands which is then underlain by a thick earth layer the Ilaro Formation and other more established Formations (Jones and Hockey, 1964). The Coastal Plains Sands spring is a multi-spring framework comprising of three spring skylines isolated by silty or clayey layers (Longe et al., 1987). It is the primary spring in Lagos Metropolis that is abused through boreholes for residential and modern water flexibly. The sedimentary rocks of Lagos State are made out of five (5) sedimentary developments (Jones and Hockey, 1964) viz: Abeokuta Formation, Ewekoro Formation, Ilaro Formation, the Coastal Plains Sands and the alluvial stores. The seaside fields sand otherwise called the Benin Formation extends over the Dahomey bowl into the Niger Delta Basin. The land arrangements of the examination territory made out of silt set down under fluviate, lascustrine and marine conditions. These residue grade into each other and fluctuate generally in parallel degree and thickness (Adepelumi and Olorunfemi 2000). Longe et al., (1987) arranged the spring into three sorts. Quantitative translation of the bends included fractional bend coordinating utilizing two-layer Schlumberger ace bends and the aux

Franklin Delano Roosevelt Essay -- Biography

On January 30, 1882, the world invited another conceived kid by the name of Franklin Delano Roosevelt that would enable America on many occasions to recoup from the profundities of mischief and threat and carry her to the shores of wellbeing. He wedded his better half and inaccessible cousin by the name of Eleanor Roosevelt and she carried out numerous beneficial things of her own. Through his training, amazing three terms of Presidency, triumph in a war, attempt for harmony, and battling through a horrendous malady know as polio, previous President Franklin D. Roosevelt was the best President ever. Franklin Roosevelt learned numerous imperative and pivotal exercises all through his instruction. Exercises and ideas that would be conveyed with him all over. One of Roosevelt's first exercises was from the author of the Groton School, Endicott Peabody. As this school was for the most part for the rich, the exercise involved that taxpayer driven organization was a fantastic technique to help those less fortunate and less special than the understudies going to the school. This good truly spoke to Roosevelt before he moved on from Groton school and went on to Harvard University (Uschan 21). At whatever point FDR's name is referenced, not very numerous individuals understand that this striking man went to Harvard. While he went to Harvard, he learned about a wide range of perspectives about government that would assist FDR with building up his political way of thinking (Uschan 22). Training played a minor however basic job for Franklin on the crucial turning into the best President up until this point. The street for FDR to become President was not unforgiving or smooth, yet it is was he did during those three amazing terms that truly makes this previous president extraordinary. FDR first term authoritatively began on March 4, 1933, and he entered term confronted with the weight o... ... second term, FDR made the National Foundation for Infantile Paralysis. He likewise made the March of Dimes, which got cash for babies with birth surrenders. He didn't life to consider the to be for polio as Roosevelt kicked the bucket in 1945. Be that as it may, the U.S congress gave FDR the special respect of having his face on the dime since he and the dime were so firmly related (FDR and Polio: Public Life, Private Pain). FDR was the best president ever through his training, amazing three terms of Presidency, triumph in a war, attempt for harmony, and for doing combating through polio. I consider all the things he has accomplished for Americans consistently, and individuals don't understand that he considerably improved the entire nation. I trust that I have passed on to you that FDR is the best president that has ever existed on this planet.